Researchers will enroll patients across six French sites who have advanced metastatic castration-resistant prostate cancer and are eligible for [177Lu]Lu-PSMA-617, also called 177Lutetium-PSMA-617. The Jean Perrin Center is the trial sponsor. Primary prostate tumor tissue will be used as the principal source for the biomarker analysis, with the central objective of identifying molecular features associated with radiological response under RECIST v1.1 and PCWG3 criteria.

The protocol addresses a clinical evidence gap in metastatic castration-resistant prostate cancer, which the investigators describe as having limited treatment options and poor survival outcomes, with an approximate five-year survival rate of 30%. Radioligand therapy with [177Lu]Lu-PSMA-617 has improved progression-free survival and overall survival in advanced disease, according to the protocol, but approximately 40% of patients do not respond. There are currently no validated predictive biomarkers for stratifying responders, and PSMA-PRED will evaluate whether molecular characteristics of tumor tissue can supply that information.

PSMA-PRED is designed as a prospective, multicentre, open-label interventional trial. Researchers will conduct comprehensive molecular profiling of tumor samples, including DNA, RNA and methylation analyses. Candidate markers will be evaluated for their association with radiological response, while the study’s secondary objectives include examining relationships between tissue biomarkers and radiological, biological and clinical progression-free survival, as well as overall survival and treatment-related toxicities.

The investigators also plan to test whether integrating molecular data with clinical, radiological or biological features can improve the performance of potential biomarker models. The protocol’s stated aim is to develop predictive models of response to [177Lu]Lu-PSMA-617 in patients with metastatic castration-resistant prostate cancer by integrating clinical, molecular and imaging data. The study was approved by the CCP Sud Ouest et Outre Mer II Ethics Committee on May 23, 2024, and registered on ClinicalTrials.gov on September 19, 2024, under the identifier NCT06600802.

These dates describe the regulatory approval and registration of the planned research. Because the published paper is a protocol, it contains no results showing that DNA, RNA or methylation markers have been discovered or validated in the enrolled population. If tissue biomarkers are identified, the investigators plan to conduct additional analyses of circulating tumor DNA at a later stage, with the aim of exploring a less invasive monitoring approach.

That work is conditional on the initial tissue findings and is not presented as an established component with completed validation. The protocol also specifies a planned cohort of 120 patients at six sites in France, limiting the current evidence to the design and scope of this multicentre study rather than establishing performance across broader populations or clinical settings. Ultimately, PSMA-PRED is intended to generate and evaluate candidate predictive biomarkers for [177Lu]Lu-PSMA-617 using a combination of tissue profiling, imaging and patient data.

Its planned endpoints include treatment response, survival measures and toxicities, allowing molecular associations to be assessed across several outcomes. Whether the resulting markers are accurate, reproducible or useful for treatment selection remains unanswered until the prospective study produces data; for now, the protocol provides a structured research framework rather than a clinically validated molecular test.

Subject of Research: Molecular biomarkers associated with response to lutetium-PSMA radioligand therapy in metastatic castration-resistant prostate cancer

Article Title: Intrinsic validity of molecular marker(s) detection on tissue tumor DNA to predict efficacy of 177Lutetium-PSMA-617 ([177Lu]Lu-PSMA-617) treatment for castration-resistant metastatic prostate cancer (PSMA-PRED): study protocol of a prospective multicentre clinical trial

Article References: Passildas, J., Ferreira, M.-C., Mahammedi, H., Merlin, C., Kelly, A., Molnar, I., Durando, X., Penault-Llorca, F., & Herrmann, T. (2026). Intrinsic validity of molecular marker(s) detection on tissue tumor DNA to predict efficacy of 177Lutetium-PSMA-617 ([177Lu]Lu-PSMA-617) treatment for castration-resistant metastatic prostate cancer (PSMA-PRED): study protocol of a prospective multicentre clinical trial. BMC Cancer. https://doi.org/10.1186/s12885-026-17143-3

Image Credits: AI Generated

DOI: 10.1186/s12885-026-17143-3

Keywords: PSMA-PRED, prostate cancer, lutetium-PSMA-617, radioligand therapy, tumor biomarkers, molecular profiling, circulating tumor DNA, clinical trial protocol, Intrinsic, validity, molecular, marker

To establish the test’s patient-specific signature, researchers compared DNA from a surgical pathology sample with DNA from a buffy-coat sample. Both sets underwent whole-genome sequencing (WGS) to generate a mutational pattern associated with the patient’s tumor. At follow-up visits, investigators extracted cell-free DNA from plasma, performed WGS and analyzed it using the patient-derived signature together with an artificial-intelligence pattern-recognition algorithm. The reported result was that positive ctDNA findings were highly sensitive markers of minimal residual disease, while negative results were strongly correlated with sustained remission in the study population.

The work was led by Matija Snuderl, MD, of NYU Langone Health and the Laura and Isaac Perlmutter Cancer Center, with co-lead investigator Harvey I. Pass, MD, of NYU Langone Health. Asaf Zviran, PhD, of C2i Genomics developed the WGS liquid-biopsy technology. The investigators said that serial monitoring across treatment stages could provide information about relapse before standard imaging detected a physical tumor. The release describes the work as an experimental study and identifies the journal article as “Predicting Recurrence of Stage IA Lung Adenocarcinoma Using Circulating Tumor Cell-Free DNA Whole-Genome Mutational Signatures.”

Patients with stage I–II non–small-cell lung cancer are usually treated with surgery, and the source reports that recurrence rates in stage I disease range from 5% to 19%. Imaging remains the standard form of follow-up after surgery or initial therapy. The study’s finding is that a blood-based molecular signal was associated with recurrence in the earliest clinical stage, at a time when the disease was not yet apparent on scans. The authors present this earlier signal as a potential basis for risk-adapted surveillance and personalized post-treatment care, but the reported study does not demonstrate that changing treatment on the basis of test results improves survival or prevents recurrence.

The source does not provide the number of participants, the timing distribution of blood collections, or numerical sensitivity, specificity or lead-time estimates. Its findings therefore support the conclusion that, in the experimental cohort, serial WGS analysis of ctDNA patterns was associated with relapse before imaging showed tumors and that negative results were associated with sustained remission. The publication’s focus on stage IA lung adenocarcinoma also limits the direct scope of the reported finding: the release describes monitoring across treatment stages, but does not establish the same performance for all stages or all forms of lung cancer.

Subject of Research: Experimental ctDNA whole-genome liquid biopsy for recurrence prediction in stage IA lung adenocarcinoma

Article Title: Novel blood test detects lung cancer traces long before scans

Article References: Novel blood test detects lung cancer traces long before scans. Original publication (Bibliographic details unavailable.)

Image Credits: AI Generated

DOI: Not provided

Keywords: lung adenocarcinoma, liquid biopsy, circulating tumor DNA, cancer recurrence, whole-genome sequencing, minimal residual disease, molecular monitoring, early-stage lung cancer, artificial intelligence, Novel, blood, test

At baseline, detectable ctDNA and a higher molecular tumor burden were each associated with shorter progression-free survival in both treatment arms. The authors said the pattern was consistent with greater underlying disease burden and intrinsic risk; the observational associations do not show that ctDNA detectability or molecular burden caused the poorer outcomes. The genomic analysis also identified adverse risk features involving MYC, the PI3K–AKT pathway and BRCA or homologous recombination repair genes.

These features characterized an adverse genomic-risk profile among the patients analyzed. PIK3CA and ESR1 status produced an exploratory treatment-informative signal, indicating that their relationship with outcomes differed according to treatment context in the analysis. In separate landmark analyses, on-treatment ctDNA clearance and reductions in molecular tumor burden were associated with favorable subsequent outcomes.

Profiling at the end of treatment identified candidate resistance-associated alterations following bireociclib, including FGFR1, MDM2 and MYC amplifications and activation of the MAPK pathway. These are candidate markers associated with treatment-emergent genomic changes, not definitive resistance biomarkers or evidence of a causal resistance mechanism. Overall, the results indicate that longitudinal ctDNA profiling may provide information for risk stratification, response monitoring and resistance tracking during CDK4/6 inhibitor-based therapy, with the analysis presented as exploratory.

Subject of Research: Longitudinal ctDNA profiling of bireociclib in advanced breast cancer

Article Title: Longitudinal ctDNA profiling reveals genomic risk and molecular response to bireociclib in advanced breast cancer

Article References: Wang, Y., Xu, H., Zhou, Y., Cui, L., Sa, Q., Cheng, H., Gao, R., Zhang, Q., Li, H., Tong, Z., Ouyang, Q., Tan, X., Bai, J., Wang, L., Duan, X., Yang, F., Wang, J., & Xu, B. (2026). Longitudinal ctDNA profiling reveals genomic risk and molecular response to bireociclib in advanced breast cancer. Nature Communications. https://doi.org/10.1038/s41467-026-78782-5

Image Credits: AI Generated

DOI: 10.1038/s41467-026-78782-5

Keywords: ctDNA, bireociclib, advanced breast cancer, BRIGHT-2 trial, genomic risk, molecular response, drug resistance, CDK4/6 inhibition, progression-free survival, PIK3CA, ESR1, MAPK pathway

The original multi-institutional analysis included 1,127 patients with metastatic breast cancer. According to the correspondence, findings involving TP53, AKT1, overall survival, disparities in PI3K inhibitor use and a survival disadvantage among Black patients relied on borderline p-values from uncorrected comparisons across 19 supplementary tables. The comment argues that accounting for multiple comparisons would strengthen the evidence for the reported associations. It also describes the genomically annotated dataset as a valuable contribution while identifying issues that require further scrutiny.

One concern is that high-deprivation patients had lower rates of visceral, nodal and soft-tissue metastasis. The comment proposes that this pattern may be consistent with reduced circulating tumor DNA shedding, which could help explain some observed differences in mutation frequencies, particularly for AKT1. The evidence available in the correspondence does not directly measure ctDNA shedding, so this remains a potential confounder rather than a demonstrated explanation. The authors call for direct assessment of ctDNA shedding when evaluating whether mutation-frequency differences reflect tumor biology or differences in detectable circulating DNA.

The correspondence also raises concerns about an AKT1 subgroup hazard ratio of 6.27 that was based on approximately five events. It notes that this falls below commonly recommended events-per-variable thresholds and calls for transparent event-count reporting. The central recommendation is to address multiplicity correction, evaluate ctDNA shedding and provide fuller details about the events underlying subgroup survival estimates. These criticisms call for cautious interpretation; they do not demonstrate that the original associations are false, nor do they resolve the independent contributions of neighborhood deprivation, tumor characteristics, treatment use and survival.

Subject of Research: Methodological scrutiny of neighborhood deprivation, tumor genomics and survival in metastatic breast cancer

Article Title: Comment on “Associations of neighborhood deprivation with breast cancer tumor genomics, targeted treatment use, and survival”

Article References: Fatima, Z., Choudhary, S., & Choudhary, H. Z. (2026). Comment on “Associations of neighborhood deprivation with breast cancer tumor genomics, targeted treatment use, and survival”. Breast Cancer Research and Treatment, 220(1), Article 9. https://doi.org/10.1007/s10549-026-08100-6

Image Credits: AI Generated

DOI: 10.1007/s10549-026-08100-6

Keywords: metastatic breast cancer, neighborhood deprivation, tumor genomics, circulating tumor DNA, PI3K inhibitors, survival analysis, multiple comparisons, health disparities, Comment, Associations, neighborhood, deprivation

The review identifies ESR1 mutations as among the most clinically relevant markers of acquired endocrine resistance. They emerge under selection pressure from aromatase inhibitors and stabilize estrogen receptor signaling in a ligand-independent manner, directly compromising estrogen-deprivation treatment while preserving the receptor as a therapeutic vulnerability. This resistance is not limited to isolated failure of CDK4/6 inhibitors. Instead, progression represents a heterogeneous resistance state within a tumor population, making the timing and interpretation of treatment changes central to the proposed sequencing strategy.

The authors describe ESR1 mutations as dynamic markers of clonal evolution rather than fixed features of a tumor. Analysis of circulating tumor DNA can detect emerging mutant clones before changes become visible on imaging, defining an interval that the review calls “molecular progression.” The PADA-1 trial established proof of concept for changing endocrine therapy at molecular progression, and the confirmatory phase III SERENA-6 trial subsequently led to regulatory approval of camizestrant, an oral selective estrogen receptor degrader, for ESR1-mutated advanced breast cancer. Vepdegestrant, described as the first proteolysis-targeting chimera estrogen receptor degrader, has also been approved in the ESR1-mutant setting. Together, these results support the feasibility of linking blood-based mutation detection with a treatment capable of targeting the altered receptor.

Beyond the pairing of a biomarker with a single drug, the review develops an ESR1-based framework for treatment sequencing after CDK4/6 inhibitor progression. It integrates emerging estrogen receptor-targeted agents, pathway-directed combinations and antibody-drug conjugates into that framework. The authors also critically appraise the available evidence for endocrine switching at molecular progression and acknowledge that important limitations remain, including the need to interpret circulating tumor DNA findings appropriately in clinical practice. The review therefore presents ctDNA-guided detection and sequencing as a developing approach for addressing heterogeneous endocrine resistance, rather than as a universal strategy for making treatment decisions before imaging-confirmed progression.

Subject of Research: ctDNA-guided ESR1 detection and treatment sequencing in advanced breast cancer

Article Title: ESR1 mutations in HR+/HER2− advanced breast cancer: ctDNA-guided detection and treatment sequencing

Article References: Zha, Y., Fan, P., Chai, Y., Liu, X., & Zhu, Y. (2026). ESR1 mutations in HR+/HER2− advanced breast cancer: ctDNA-guided detection and treatment sequencing. Journal of Translational Medicine. https://doi.org/10.1186/s12967-026-09090-1

Image Credits: AI Generated

DOI: 10.1186/s12967-026-09090-1

Keywords: ESR1 mutations, advanced breast cancer, circulating tumor DNA, endocrine resistance, molecular progression, estrogen receptor, camizestrant, vepdegestrant, CDK4/6 inhibitors, treatment sequencing, ESR1, mutations

Minimal residual disease, or MRD, refers to the small population of cancer cells that persists after curative-intent treatment. These cells are typically undetectable by conventional imaging but can be identified through sensitive molecular methods such as next-generation sequencing, quantitative polymerase chain reaction and circulating tumor DNA analysis. In hematologic malignancies such as acute lymphoblastic leukemia, MRD has long been established as a robust prognostic indicator, and its relevance in solid tumors is increasingly recognized. The clinical data are striking. In one study of 299 patients with stage I to III colorectal cancer, patients whose ctDNA tested positive for any one of six methylation markers one month after surgery were 17.5 times more likely to experience recurrence than those with negative results. In non-small cell lung cancer, ctDNA was detected before treatment in 24 percent of stage I patients, 77 percent of stage II patients and 87 percent of stage III patients, and post-treatment detection of ctDNA was associated with unfavorable clinical outcomes.

Within this reservoir, drug-tolerant persister cells occupy a pivotal and paradoxical position. The concept originates from microbiology, where persister describes bacterial cells that survive antibiotic exposure through non-genetic mechanisms. In 2010, researchers extended this analogy to human cancer when they identified DTP cells in EGFR-mutant lung cancer cells treated with the EGFR inhibitor erlotinib. Despite lethal drug concentrations, a small fraction of cells persisted in a reversible drug-tolerant state characterized by quiescence and epigenetic reprogramming, distinguishing them from genetically resistant mutants. Three core functional assays now define bona fide DTP populations. In a reversibility assay, DTP cells regain full drug sensitivity and proliferative capacity after drug withdrawal for seven to fourteen days, whereas permanently resistant clones maintain stable insensitivity driven by fixed genetic alterations such as EGFR T790M or BRAF V600E secondary mutations. Single-cell sequencing confirms that DTP cells carry no stable driver resistance mutations, relying purely on epigenetic and metabolic adaptive plasticity. Clonal fluctuation testing shows that DTP populations do not produce stable resistant sublines upon continuous passaging without drug pressure.

The review proposes a hierarchical model that clarifies why these cells matter so much. MRD consists of all heterogeneous residual cancer cells that persist after therapy, covering three distinct subpopulations: therapy-sensitive dormant tumor cells, genetically stable permanent resistant clones, and transient drug-tolerant DTP cells. DTP cells exclusively embody the plastic, non-genetic tolerant faction within MRD, surviving initial cytotoxic treatments through reversible epigenetic, metabolic and cell-cycle adaptive mechanisms, and serving as the critical intermediate reservoir en route to stable acquired resistance. This positioning explains why DTP cells, rather than other MRD components, are the primary initiators of tumor recurrence. In acute myeloid leukemia, MRD identified by flow cytometry frequently includes quiescent cells with persister-like characteristics, indicating a functional connection between the two concepts.

The biological toolkit that DTP cells deploy is remarkably diverse. A prominent feature is cell cycle arrest in the G0/G1 phase, rendering them quiescent and less susceptible to therapies targeting proliferating cells. In HER2-positive breast cancer, HER2 inhibitor treatment induces DTP cells with either luminal epithelial-like or mesenchymal-like transcriptional profiles, and tumor cells stochastically and cyclically enter a G0-like pre-DTP state enriched for dormancy and diapause-associated genes. Metabolic reprogramming represents another adaptation. Under MAPK inhibitor treatment, a subset of lung adenocarcinoma cells shifts from glycolysis to mitochondrial respiration, rendering them highly dependent on antioxidant pathways to mitigate elevated reactive oxygen species. DTP cells also bolster anti-apoptotic mechanisms by upregulating proteins such as MCL-1, and during DTP formation, downregulation of MYC relieves transcriptional repression of PINK1, activating mitophagy that eliminates damaged mitochondria and maintains metabolic homeostasis under therapeutic stress.

The tumor microenvironment plays a decisive role in fostering these cells. Hypoxia, a hallmark of solid tumors, promotes DTP survival by stabilizing hypoxia-inducible factor-1 alpha, which upregulates glycolytic enzymes and anti-apoptotic genes. Under hypoxic or nutrient-deprived conditions, melanoma cells acquire a DTP state conferring resistance to BRAF inhibitors and platinum-based chemotherapies, accompanied by extensive chromatin remodeling. Cancer-associated fibroblasts contribute to DTP induction through balanced regulation of TGF-beta and NF-kappaB signaling. During EGFR inhibitor treatment, fibroblasts transition from a myofibroblastic phenotype to a novel state marked by activation of NF-kappaB and IL-6/JAK/STAT3 signaling, further enhancing DTP drug tolerance. Notably, substantial infiltration of Ccr2-positive macrophages occurs when tumor volume reaches its nadir and enters the DTP phase, coinciding with the transition of tumor cells from a reversible drug-tolerant state to an acquired resistant state.

Metabolic and redox adaptations offer some of the most exploitable vulnerabilities. In BRAF V600E-mutant melanoma, DTP cells develop tolerance to BRAF and MEK inhibitors by shifting from glycolysis to peroxisomal fatty acid oxidation, a process transcriptionally regulated by the PPAR alpha-ACOX1 axis. DTP cells also upregulate Lipin1, a fatty acid esterification enzyme, promoting lipid droplet formation to mitigate lipotoxicity. In obesity-associated colorectal cancer, the FABP4/UCP2 axis drives cetuximab resistance when DTP cells are co-cultured with adipocytes. Across multiple treatment contexts, including BRAF, MEK, ALK and androgen receptor inhibitor-treated tumors, DTP cells show reduced glycolysis but increased oxidative phosphorylation and redox regulation. Persister cells that survive treatment tend to adopt a high-mesenchymal state and become reliant on glutathione peroxidase 4 to detoxify lipid peroxides, thereby evading ferroptosis, an iron-dependent form of cell death. In ALK-positive lung cancer, DTP cells surviving ALK inhibitor treatment upregulate GPX4 to evade ROS-induced cytotoxicity.

Epigenetic reprogramming is a frequent feature of DTP biology. In melanoma under hypoxic or nutrient-deprived conditions, DTP cells acquire resistance through chromatin remodeling characterized by the loss and gain of epigenetic marks such as H3K9me3. Upregulation of O-GlcNAc transferase, in synergy with TET1, promotes H3K4me3 deposition at CpG islands via the hexosamine biosynthesis pathway, driving the transition from a dormant DTP state to a proliferative drug-tolerant persister-proliferative state that manifests as acquired resistance. In BRAF-mutant melanoma treated with combined RAF and MEK inhibition, MRD harbors co-existing DTP populations with pronounced transcriptional and spatial heterogeneity, including a key subpopulation displaying a neural crest stem cell-like program driven by RXRG signaling. Cells that survive lethal drug pressure also enhance methylation of histone H3K9 and H3K27 at LINE-1 repetitive elements, suppressing drug-induced activation of repetitive elements and interferon-stimulated genes.

On the therapeutic front, the review highlights several mechanism-based strategies. The Notch signaling pathway has emerged as an actionable target in lung cancer, where Notch1 and its target genes are upregulated in osimertinib-treated DTP cells, and gamma-secretase inhibitors significantly suppress DTP survival. Combining osimertinib with these inhibitors markedly downregulates phosphorylated ERK and enhances DUSP1 expression, and clinical tissue samples corroborate Notch1/HES1 upregulation following EGFR inhibitor treatment in patients. Epigenetic regulation serves as a cornerstone for DTP-targeted therapies. In melanoma, ALDH1A3 cooperates with ACSS2 in the nucleus to convert glucose metabolic flux into acetyl-CoA, promoting histone H3 acetylation and activating genes associated with the neural crest stem cell-like state. Pharmacological inhibition of ALDH1 delays or prevents relapse after BRAF inhibitor therapy. AMPK activators such as aspirin downregulate OGT expression, preventing DTPP formation and delaying acquired resistance. Autophagy offers a third avenue, as blocking autophagy with chloroquine in combination with chemotherapy eliminates DTP survival in colorectal cancer, and inhibiting PINK1 or mitophagy effectively eliminates DTP cells and enhances sensitivity to targeted therapies.

Translating these insights into clinical practice faces real hurdles. The heterogeneity of DTP cells across cancer types and treatment contexts necessitates robust biomarkers to identify and monitor these populations, and the dynamic plasticity of DTP cells complicates therapeutic strategies as they transition between drug-tolerant and drug-sensitive states. Toxicity associated with combination therapies must be carefully managed, and a gap persists between preclinical models and human tumors, where heterogeneity, off-target effects and resistance mechanisms often diminish therapeutic efficacy. Consensus on MRD thresholds and survival correlates remains unresolved, and aggressive DTP-targeting regimens may increase toxicity, raising concerns about quality of life versus survival gains. Yet emerging technologies offer reason for optimism. Single-cell omics, spatial transcriptomics, digital PCR, live-cell imaging and multiplexed ion beam imaging are pushing detection limits toward ultra-rare DTP cells, while artificial intelligence and machine learning are being deployed to identify DTP signatures, predict relapse and optimize therapies. Adaptive therapy approaches that modulate treatment intensity based on tumor response are being tested to prevent the emergence of DTP populations, and liquid biopsy technologies are being developed to detect circulating DTP cells and DTP-derived ctDNA for real-time MRD monitoring. If these threads converge, the review concludes, targeting DTP cells within MRD holds transformative potential to dismantle the persister niche, prevent relapse and reshape long-term cancer outcomes.

Subject of Research: Cancer drug-tolerant persister cells and minimal residual disease

Article Title: Erasing the invisible: targeting persister cells to cure minimal residual disease

Article References: Wang, Y., Shi, Z., Xu, F., Zhu, Y., Liu, C., Wang, B., Ji, N., Wang, Z., Wang, S., Zhou, X., & Ren, Y. (2026). Erasing the invisible: targeting persister cells to cure minimal residual disease. Holistic Integrative Oncology, 5(1), 81. https://doi.org/10.1007/s44178-026-00307-3

Image Credits: AI Generated

DOI: 10.1007/s44178-026-00307-3

Keywords: minimal residual disease, drug-tolerant persister cells, cancer relapse, epigenetic reprogramming, metabolic reprogramming, tumor microenvironment, ferroptosis, autophagy, liquid biopsy, single-cell sequencing, targeted therapy, drug resistance

The review emphasizes that resistance is not a single event but a heterogeneous, evolving process. Clinically, it is classified as primary—relapse within the first two years of adjuvant endocrine therapy or progression within six months of first-line treatment for advanced disease—or secondary, which encompasses later relapses and progression on subsequent lines. According to the updated ABC6/7 consensus definitions, the presence of a known ESR1 mutation also falls under secondary resistance. In practice, the authors argue, endocrine sensitivity and resistance are better understood as a continuum, interpreted alongside prior treatment exposure, disease tempo, and molecular biomarkers rather than rigid categories.

At the molecular level, the most direct route to resistance runs through the estrogen receptor gene itself, ESR1. Mutations in this gene are exceedingly rare in untreated primary tumors but climb to approximately 20 to 40 percent in metastatic disease after aromatase inhibitor therapy. The most common alterations, Y537S and D538G, cluster in the ligand-binding domain of the receptor. These missense mutations change the receptor’s three-dimensional conformation so that it recruits coactivators and drives transcription continuously, even without estrogen. This ligand-independent activation renders aromatase inhibitors—which work by depleting estrogen—ineffective, and it also weakens the binding of fulvestrant, the first-generation selective estrogen receptor degrader, producing partial cross-resistance.

Whole-transcriptome sequencing has uncovered a second structural mechanism: ESR1 gene fusions. In endocrine-resistant metastatic lesions, researchers have identified fusions such as ESR1–YAP1 and ESR1–CCDC170. When ESR1–YAP1 forms, the potent transcriptional activation domain of YAP1 replaces the receptor’s ligand-binding domain, allowing estrogen-independent growth. ESR1–CCDC170 takes a different route, forming a complex with HER2, HER3, and SRC that activates the SRC–PI3K–AKT pathway; knocking down this fusion reduces HER2/HER3 expression and restores endocrine sensitivity. Beyond these structural changes, resistant cells undergo broader transcriptional reprogramming, in which epigenetic modifications enhance ER binding at specific chromatin sites and sustain the transcriptional programs tumors need to survive—a phenomenon the authors call transcriptional dependency, which complicates any single-target strategy.

When the ER pathway is pharmacologically blocked, tumor cells frequently reroute their signaling through growth factor pathways, a process known as crosstalk. The PI3K/AKT/mTOR pathway has attracted the most attention: roughly 40 percent of HR+/HER2− patients harbor activating PIK3CA mutations, which drive proliferation and can induce ligand-independent phosphorylation of ER through downstream kinases such as S6K1. Conversely, when endocrine therapy suppresses ER signaling, the negative feedback ER normally exerts is released, AKT phosphorylation rises, and receptor tyrosine kinase signaling through HER3 and IGF1R intensifies. Even without HER2 amplification, ligand-driven HER2/HER3 heterodimerization can activate SRC/PI3K/AKT signaling and, through the HER2/HER3–HDAC2–FOXA1 axis, reshape ER transcription by redirecting the receptor toward resistance, invasion, and metastasis loci. The authors caution that HER2-low or HER2-ultralow classifications are treatment-selection descriptors for antibody–drug conjugates, not mechanisms of resistance in themselves.

Resistance to CDK4/6 inhibitors follows its own logic. These drugs work by arresting the cell cycle at the G1-to-S transition, an effect that depends on an intact retinoblastoma (Rb) protein. When the RB1 gene is lost or mutated, E2F transcription factors escape suppression, the cell cycle proceeds, and cells become less dependent on the CDK4/6–Cyclin D1 complex. Although RB1 inactivation is not highly frequent in metastatic HR+/HER2− disease, its impact is well defined: among patients treated with palbociclib plus fulvestrant, those with RB1 loss show markedly shorter progression-free survival. Additional escape routes include amplification of Cyclin E1 or overexpression of CDK2, which allow cells to rely on the Cyclin E–CDK2 complex, and loss of FAT1, which inactivates the Hippo pathway. Single-cell studies also implicate the tumor microenvironment, where immunosuppressive cell populations expand under the selective pressure of CDK4/6 inhibition.

These mechanistic insights are now being translated into drugs. Next-generation oral selective estrogen receptor degraders, or SERDs, offer better bioavailability than injectable fulvestrant. Elacestrant, the first approved oral SERD, significantly prolonged progression-free survival versus standard endocrine therapy in ESR1-mutated patients previously treated with a CDK4/6 inhibitor in the phase III EMERALD trial. Camizestrant outperformed fulvestrant regardless of ESR1 status in SERENA-2, and imlunestrant, another oral SERD, extended median progression-free survival to 5.5 versus 3.8 months in ESR1-mutated patients in EMBER-3; when combined with abemaciclib, imlunestrant achieved 10.9 versus 5.5 months, and the FDA approved imlunestrant on September 25, 2025 for ESR1-mutated advanced disease after at least one prior endocrine line. A parallel approach uses PROTACs—proteolysis-targeting chimeras such as vepdegestrant (ARV-471)—which hijack the cell’s ubiquitin–proteasome machinery to degrade ER directly, with preclinical degradation exceeding 90 percent. In the phase III VERITAC-2 trial, vepdegestrant doubled median progression-free survival to 5.0 versus 2.1 months in the ESR1-mutated cohort, though the overall population showed no significant benefit, underscoring the importance of biomarker selection. Complete estrogen receptor antagonists, or CERANs such as OP-1250, block both ER transcriptional activation domains while promoting receptor degradation, and preclinical data suggest possible blood–brain barrier penetration.

Bypass signaling has yielded its own arsenal. Inavolisib, a selective PI3Kα inhibitor that also promotes degradation of the mutant p110α protein, extended median progression-free survival to 15.0 versus 7.3 months and median overall survival to 34 versus 27 months in the phase III INAVO120 trial when added to palbociclib and fulvestrant in first-line PIK3CA-mutated disease. The pan-AKT inhibitor capivasertib, tested with fulvestrant in CAPItello-291, improved median progression-free survival to 7.2 versus 3.6 months overall and 7.3 versus 3.1 months in tumors with PIK3CA, AKT1, or PTEN alterations, with some benefit even in pathway-wild-type tumors. On the mTOR front, everolimus plus exemestane raised median progression-free survival from 4.1 to 10.6 months by central assessment in BOLERO-2, though at the cost of grade 3–4 stomatitis, infections, rash, and hyperglycemia. The multitargeted inhibitor gedatolisib, which blocks multiple PI3K isoforms and mTORC1/2 simultaneously, achieved 9.3 versus 2.0 months in PIK3CA wild-type disease after CDK4/6 progression in VIKTORIA-1, with relatively low rates of hyperglycemia and stomatitis, and received FDA approval in combination with fulvestrant, with or without palbociclib, on July 14, 2026.

Perhaps the most striking shift is toward acting before tumors visibly progress. Liquid biopsy studies show that circulating tumor DNA can detect ESR1 mutations in 20 to 50 percent of previously treated metastatic cases, often predicting poorer aromatase inhibitor responses. In the randomized PADA-1 trial, switching from an aromatase inhibitor to fulvestrant—both with palbociclib—as soon as rising ESR1 mutation levels were detected in ctDNA significantly prolonged median progression-free survival. The phase III SERENA-6 trial went further: patients on first-line aromatase inhibitor plus CDK4/6 therapy whose ctDNA revealed emergent ESR1 mutations, but who had no radiographic progression, were switched to camizestrant while continuing the same CDK4/6 inhibitor. The extended analysis showed median progression-free survival of 16.8 versus 9.2 months and second progression-free survival of 25.7 versus 19.1 months—compelling evidence that molecular progression can be intercepted before clinical relapse. The authors note that assay performance is platform-specific: droplet digital PCR excels at tracking predefined ESR1 hotspots with detection limits of 0.07 to 0.19 percent mutant allele fraction, while targeted next-generation sequencing offers broader coverage but platform-dependent sensitivity, and negative plasma results should prompt repeat or tissue-based testing when suspicion is high.

The review also maps the frontier beyond established targets. Epigenetic therapies, including EZH2 inhibitors such as tazemetostat and HDAC inhibitors, aim to reverse the chromatin states that sustain resistant transcriptional programs. Metabolic reprogramming offers another angle: resistant cells increasingly depend on fatty acid oxidation and oxidative phosphorylation, with CPT1A-mediated transport of long-chain fatty acids into mitochondria sustaining ATP production in slow-cycling persister cells; the CPT1 inhibitor etomoxir showed greater activity in resistant than sensitive cells in preclinical models, though such approaches remain investigational. After endocrine resistance is established, antibody–drug conjugates provide antigen-directed options: sacituzumab govitecan improved survival in heavily pretreated patients in TROPiCS-02, and datopotamab deruxtecan was FDA-approved in January 2025 for previously treated metastatic HR+/HER2− disease. The authors conclude that no single biomarker captures the full resistance landscape, and that integrating multi-omics analysis, single-cell sequencing, and dynamic ctDNA monitoring will be essential to move clinical management from empiric treatment switching toward truly individualized, mechanism-guided, whole-course care.

Subject of Research: Molecular mechanisms of endocrine resistance and emerging targeted therapies in HR-positive/HER2-negative breast cancer

Article Title: Endocrine resistance in HR+/HER2− breast cancer: molecular mechanisms and emerging therapeutic strategies

Article References: Shen, T., Li, H., Zhang, X., & Zhou, Q. (2026). Endocrine resistance in HR+/HER2− breast cancer: molecular mechanisms and emerging therapeutic strategies. Frontiers in Oncology, 16, Article 1983430. https://doi.org/10.3389/fonc.2026.1983430

Image Credits: AI Generated

DOI: 10.3389/fonc.2026.1983430

Keywords: endocrine resistance, HR-positive HER2-negative breast cancer, ESR1 mutations, oral SERDs, PROTAC, PI3K/AKT/mTOR pathway, CDK4/6 inhibitors, circulating tumor DNA, liquid biopsy, antibody-drug conjugates, epigenetic therapy, precision oncology

Firmonertinib was designed with this structural insight in mind. As an allosterically oriented kinase inhibitor, it was engineered to maintain activity against a broader spectrum of EGFR conformations, including the compressed catalytic cleft characteristic of PACC variants. The preclinical finding that tumor growth inhibition frequently exceeded 90 percent across multiple PACC subtypes in cell lines and patient-derived xenograft models is notable because PACC mutations are not a single alteration but a family of related changes scattered across exons 18 through 21, including variants such as G719X, S768I, L747P, and V769L, among others. Demonstrating consistent activity across this heterogeneous group suggests that the drug’s binding mode is tolerant of the structural variation within the PACC class rather than being narrowly tailored to one specific mutation. This breadth matters clinically, because patients with uncommon EGFR mutations are individually rare, and a therapy that requires a separate trial for each variant would be impractical to develop and difficult to access.

The dose-response relationship observed in the FURTHER trial deserves careful consideration. The higher 240 mg daily dose produced both a higher objective response rate of 68 percent and a longer median progression-free survival of 16 months compared with 11.1 months at 160 mg among previously untreated patients. In early-phase oncology trials, dose escalation is often constrained by tolerability, and the fact that the trial explored two dose levels and observed a meaningful separation in efficacy endpoints will inform how the ongoing Phase 3 ALPACCA study is designed and dosed. It is worth noting that progression-free survival figures of this magnitude in a first-line setting for a molecularly defined subgroup are approaching the range historically associated with osimertinib in classical EGFR-mutant disease, which is precisely the comparator that ALPACCA will test head-to-head. That randomized comparison will be the definitive test of whether structure-guided drug selection translates into a survival or durability advantage over the current standard of care, since single-arm Phase 1b results, however encouraging, are subject to selection biases and small-sample limitations inherent to 60-patient cohorts.

The intracranial activity reported in the trial addresses one of the most clinically consequential challenges in EGFR-mutant lung cancer. Brain metastases occur in a substantial proportion of patients with EGFR-driven disease over the course of their illness, and the blood-brain barrier has historically limited the penetration of many targeted agents. Among the 17 patients with baseline brain metastases, the 47 percent intracranial response rate and the 41 percent complete intracranial response rate are striking, particularly because responses were seen in lesions that had never received prior radiation. Complete disappearance of brain lesions on imaging is an uncommon and clinically meaningful outcome, since intracranial disease often drives morbidity and mortality in this population. The ability of firmonertinib to achieve these results suggests favorable central nervous system penetration, though the small number of evaluable patients means these figures carry wide confidence intervals and will need confirmation in the larger randomized setting.

The ctDNA findings may prove to be among the most consequential aspects of the study over time. Circulating tumor DNA analysis offers a noninvasive window into tumor dynamics, and the observation that 80 percent of evaluable patients achieved complete clearance of their EGFR PACC mutations from the blood during treatment provides both a pharmacodynamic signal and a potential early predictor of benefit. The correlation between ctDNA clearance and longer progression-free survival aligns with a growing body of literature across multiple cancer types showing that early molecular response on liquid biopsy often precedes radiographic response and correlates with durability. If prospective validation confirms that ctDNA kinetics reliably identify patients deriving benefit, this could eventually support adaptive treatment strategies, in which patients whose mutations fail to clear early might be candidates for escalation or combination approaches before radiographic progression becomes evident. Conversely, patients with rapid and complete clearance might be candidates for de-escalation strategies aimed at reducing chronic toxicity burden, since EGFR-directed therapy is typically administered continuously until progression.

The epidemiologic context underscores why this work matters at a population level. Lung cancer remains the leading cause of cancer death worldwide, and while EGFR mutations account for only 5 to 10 percent of all lung cancers in unselected populations, this fraction rises substantially in certain demographics, particularly among East Asian populations and in never-smokers, where EGFR mutation frequencies can approach 50 percent of lung adenocarcinomas. Within that EGFR-mutant population, PACC mutations at roughly 12 percent represent a meaningful share of patients, translating to tens of thousands of individuals globally each year who currently receive therapies not designed for their tumor’s specific structural biology. The rarity of any individual uncommon EGFR variant has historically made it difficult to mount adequately powered trials, which is precisely why the structural classification approach is attractive: it allows a single drug development program to serve a biologically coherent group of mutations rather than chasing each variant individually.

The ALPACCA Phase 3 trial will be pivotal in several respects. By randomizing patients to firmonertinib versus osimertinib or afatinib as first-line therapy, it directly tests whether structure-guided selection outperforms the existing standard. Osimertinib is a third-generation EGFR inhibitor with established efficacy in classical EGFR mutations and documented central nervous system activity, while afatinib is a second-generation agent with broader wild-type EGFR activity that has shown some effectiveness in certain uncommon mutations. The choice of these specific comparators reflects the current landscape of EGFR-directed therapy, in which clinicians have had to extrapolate from small studies and mechanistic reasoning to select agents for patients with uncommon variants. A positive Phase 3 result would establish firmonertinib as a new standard of care for this subgroup and would validate the broader principle that structural mutation classification can serve as a foundation for drug development, not merely a laboratory curiosity.

Several questions remain open as this program matures. The durability of responses beyond the median, the long-term tolerability profile at the 240 mg dose, and the activity of firmonertinib in patients who have already received prior EGFR-directed therapy are all areas where additional data will be needed. The trial enrolled previously untreated patients for the headline efficacy figures, but real-world populations include many patients who progressed on earlier lines of therapy, and resistance mechanisms to firmonertinib, whether through acquisition of secondary EGFR mutations such as C797S or through bypass pathway activation, remain to be characterized. Additionally, the interplay between firmonertinib and concurrent treatments for brain metastases, including stereotactic radiosurgery, will require study as more patients with CNS disease receive the drug. The biomarker work on ctDNA is also at an early stage, and the researchers themselves note that future studies are needed to determine whether ctDNA dynamics can formally inform treatment decisions rather than simply correlate with outcomes. As the ALPACCA trial accrues and matures, and as ctDNA validation studies progress, the field will learn whether the structural classification of EGFR mutations can be extended to other kinase-driven cancers, where similar conformational subgroups may await targeted drug design.

Subject of Research: Structurally guided therapy shows promise for patients with specific EGFR-mutated lung cancer in Phase 1b trial

Article Title: Structurally guided therapy shows promise for patients with specific EGFR-mutated lung cancer in Phase 1b trial

Article References: Structurally guided therapy shows promise for patients with specific EGFR-mutated lung cancer in Phase 1b trial. Original publication (Bibliographic details unavailable.)

Image Credits: AI Generated

DOI: Not provided

Keywords: EGFR PACC mutations, firmonertinib, non-small cell lung cancer, Phase 1b FURTHER trial, MD Anderson Cancer Center, circulating tumor DNA, brain metastases, Cancer Cell, Structurally, guided, therapy, shows

The appeal of these compartments lies in basic physics and biology. Plasma-based liquid biopsy has transformed oncology by detecting circulating tumor DNA, or ctDNA, the fragments of tumor genome released into the bloodstream when cancer cells die through apoptosis or necrosis. But blood is a highly diluted medium, contaminated with abundant DNA from dying white blood cells, and the blood-brain barrier actively excludes tumor DNA shed by metastases in the brain or its protective membranes. Fluids that sit in direct contact with tumor deposits face neither problem. Ascites bathing peritoneal metastases, pleural fluid in contact with lung tumors, and cerebrospinal fluid surrounding the central nervous system all receive tumor-derived DNA at high local concentrations, with far less background genetic noise from peripheral blood cells. The result is a signal that is not only stronger but, in some cases, fundamentally different from what blood or a single needle biopsy of tissue can provide.

The research team, led by investigators including Aditya Shreenivas and Razelle Kurzrock, profiled fluid samples using a next-generation sequencing platform capable of detecting point mutations, copy number alterations, splice variants, indels, and gene fusions. The cohort of 45 patients, with a median age of 52, included 18 men and 27 women, and spanned lung cancer, breast cancer, ovarian cancer, pancreatic cancer, and a collection of rarer malignancies. Ascitic fluid accounted for 26 samples, pleural fluid 11, cerebrospinal fluid seven, and pericardial fluid one. The overall ctDNA detection rate was a striking 87 percent, with ascites performing best at 96 percent, pleural fluid at 72.7 percent, and cerebrospinal fluid at 71.4 percent. The single pericardial sample was also positive, though the authors caution that one case proves little. These rates, while descriptive rather than definitive performance estimates, underline how readily tumors seed their genetic material into the cavities they invade.

The mutational landscape the sequencing revealed was dominated by familiar oncogenic players. TP53, the guardian-of-the-genome gene whose loss is a hallmark of nearly all cancers, was altered in 49 percent of samples. EGFR and KRAS, two of the most clinically consequential oncogenes in lung and gastrointestinal malignancies, were each altered in 18 percent of patients, with co-existing EGFR amplifications detected in three cases that also carried sensitizing EGFR mutations. PIK3CA and FGFR3 each appeared in 9 percent of patients, GNAS and MYC in 7 percent, and CTNNB1 and the estrogen receptor gene ESR1 in 4 percent each. Amplifications were present in 20 percent of the cohort, most frequently affecting EGFR and MYC. No gene fusions or rearrangements were detected, a negative finding the authors report explicitly.

Perhaps the most clinically electrifying numbers came from the variant allele frequency analysis, a measure of what fraction of the cell-free DNA in a sample carries the mutation in question. Cerebrospinal fluid posted a median VAF of 23.2 percent, an order of magnitude higher than the 0.65 percent median typically achievable in plasma, reflecting the fluid’s remarkable purity and minimal contamination from blood-derived genomic DNA. Pleural fluid showed a median VAF of 6.5 percent and ascites 1.23 percent, while the lone pericardial sample harbored an EGFR mutation at a VAF of 70 percent. Such high fractions mean that even modest sequencing depth can reliably detect clinically relevant alterations in these fluids, potentially enabling the identification of low-frequency mutations and structural variants that current plasma-based platforms struggle to resolve.

To translate raw mutation lists into clinical meaning, the researchers classified every alteration using the ESCAT framework, the European Society for Medical Oncology’s scale for ranking the actionability of molecular targets. Roughly 31 percent of patients carried tier IA alterations, meaning mutations with approved targeted therapies for their specific tumor type, almost all of them in breast or lung cancer. Another 35.6 percent fell into tier IIIA, where drugs have proven benefit in the same molecular subtype but a different tumor type, and 53.3 percent carried tier IVA alterations supported only by preclinical evidence, highlighting unmet opportunities for clinical trial enrollment. The take-home message is that fluid profiling is not merely academic; the alterations it finds map directly onto therapies that already exist or are in development.

Even more provocative were the six patients whose fluids harbored therapeutically relevant alterations that were entirely absent from matched tissue and blood samples. One woman with breast cancer had an ERBB2 amplification detectable only in her ascites, a finding that opens the door to multiple FDA-approved HER2-directed drugs. Another breast cancer patient carried the ESR1 D538G resistance mutation, targetable with agents including elacestrant and fulvestrant, in her cerebrospinal fluid alone. A gastrointestinal stromal tumor patient had a KIT mutation in pleural fluid that imatinib can inhibit, and three patients, one with ovarian and two with pancreatic cancer, showed FGFR3 amplifications or KRAS G12V mutations exclusively in ascitic fluid. These discordances are the molecular fingerprint of spatial and temporal tumor heterogeneity: different metastatic sites evolve different resistance mechanisms, and local shedding enriches the adjacent fluid with clones that a single tissue biopsy or diluted plasma sample simply cannot see.

The concordance analysis quantified this incompleteness of conventional sampling. Among 16 patients with both fluid and blood profiling, only half shared at least one oncogenic alteration between the two sample types. Of 11 patients with matched tissue comparisons, seven showed overlapping alterations, and when all three sample types were compared simultaneously in seven patients, just three displayed fully concordant profiles. Cytology comparisons told a complementary story: of five cytology-negative fluid samples, four were positive for ctDNA, meaning molecular analysis flagged malignancy that the microscope had missed. The reverse also occurred, with three of twenty cytology-positive samples testing negative by sequencing, a pattern that reinforces the authors’ argument that the two approaches are complementary rather than competing. Fluid cytology retains formal staging importance, contributing, for example, to FIGO stage III classification in ovarian cancer, but ctDNA analysis catches cases cytology alone would miss.

The study is candid about its limitations. It was retrospective, exploratory, and descriptive, with a small and heterogeneous cohort, no formal statistical hypothesis testing, and representation of pericardial fluid limited to a single case. Matched samples were not available for every patient, timing differences between fluid, tissue, and plasma collection may have contributed to discordance through clonal evolution under therapeutic pressure, and platform differences in panel design and sequencing depth cannot be fully excluded as sources of the observed discrepancies. ESCAT tiers link drugs to mutations but do not demonstrate that any individual patient benefited from matching therapy. The authors explicitly frame their detection rates as preliminary observations that require prospective validation in larger, disease-specific cohorts with standardized sampling.

Even with those caveats, the implications are difficult to ignore. Effusions and cerebrospinal fluid are collected routinely from advanced cancer patients, often repeatedly, yet their genomic content has been largely discarded after the cytology slide is read. The new findings, consistent with prior reports of EGFR amplification found in ascites but not tissue, and with NCCN guidelines that already recommend considering CSF tumor DNA testing when leptomeningeal disease is suspected, suggest that these fluids deserve a formal place in precision oncology workflows. Body fluids sidestep the clonal hematopoiesis false positives that plague plasma sequencing, they can be sampled when tissue biopsy is unsafe or infeasible, and they capture the regional biology of metastatic sites that governs how each deposit will respond to treatment. If prospective trials confirm these descriptive signals, the cloudy fluid drained from a patient’s chest or abdomen may become as informative as any gene panel, transforming a routine byproduct of cancer care into a real-time map of the tumor’s evolving vulnerabilities.

Subject of Research: Circulating tumor DNA analysis of non-blood body fluids for cancer detection and molecular profiling

Article Title: Circulating tumor DNA in body fluids for molecular characterization of cancers beyond tissue and blood

Article References: Shreenivas, A., Limaye, S., Cristofanilli, M., Lechner, M., Gaya, A. M., Crook, T., Leite, P., Mokbel, K., Schaffrin-Nabe, D., Al-Shamsi, H. O., Patil, D., Datar, R., & Kurzrock, R. (2026). Circulating tumor DNA in body fluids for molecular characterization of cancers beyond tissue and blood. iScience, 29(11), Article 117893. https://doi.org/10.1016/j.isci.2026.117893

Image Credits: AI Generated

DOI: 10.1016/j.isci.2026.117893

Keywords: liquid biopsy, circulating tumor DNA, ascites, cerebrospinal fluid, pleural effusion, cytology, precision oncology, tumor heterogeneity, ESCAT, next-generation sequencing, EGFR, ERBB2

The stakes of catching the disease early could hardly be higher. When pancreatic cancer is diagnosed at an early, localized stage, five-year survival rates climb from less than 10 percent to nearly 35 to 50 percent. Yet no population-wide screening program exists, because the disease is relatively uncommon and there is no reliable, non-invasive test capable of finding it in asymptomatic people. The most widely used blood marker, carbohydrate antigen 19-9, is elevated in only about 70 to 80 percent of patients and performs poorly in early-stage disease. Its levels also rise in benign conditions such as pancreatitis, cholangitis and biliary obstruction, and roughly 5 to 10 percent of the population is Lewis antigen-negative and simply cannot produce the marker at all, producing false negatives. CA 19-9 therefore remains useful mainly as an adjunct in symptomatic patients and for monitoring treatment response, not as a standalone screening tool.

Given these constraints, the field has converged on a targeted strategy: identify the people most likely to develop the disease and surveil them intensively. Family history is a powerful starting point. Approximately 10 to 15 percent of pancreatic ductal adenocarcinoma cases occur in individuals with a positive family history or an identifiable hereditary syndrome, and data from the Pancreatic Cancer Case–Control Consortium estimate the heritability of the disease at about 21.2 percent. The risk roughly doubles with one affected first-degree relative, increases six-fold with two, and may exceed a thirty-fold increase when three or more close relatives are affected. Familial pancreatic cancer, defined by two or more affected first-degree relatives, accounts for roughly 5 to 10 percent of all cases.

Specific inherited mutations sharpen this risk stratification considerably. Germline mutations in BRCA2, best known for hereditary breast and ovarian cancer, raise pancreatic cancer risk five- to ten-fold, while BRCA1 confers a somewhat smaller increase. Mutations in CDKN2A, linked to familial atypical multiple mole melanoma syndrome, may raise risk thirty- to forty-fold, and Peutz-Jeghers syndrome, caused by STK11 mutations, carries one of the highest lifetime risks of all, prompting surveillance to begin as early as the third or fourth decade of life. Hereditary pancreatitis driven by PRSS1 mutations carries a lifetime risk that may reach 40 to 55 percent, especially among long-term smokers. Lynch syndrome, arising from mismatch repair gene defects such as MLH1 and MSH2, increases risk roughly six- to eight-fold. The International Cancer of the Pancreas Screening consortium recommends that carriers of these high-penetrance variants undergo surveillance with magnetic resonance imaging, magnetic resonance cholangiopancreatography or endoscopic ultrasound, typically starting at age 50 or ten years before the youngest affected family member’s diagnosis. Evidence from CAPS studies shows this targeted approach can detect precancerous lesions and early-stage tumors, increasing the likelihood of curative surgery.

One of the most intriguing clinical clues, however, requires no genetic test at all. New-onset diabetes in people over 50 has emerged as a potential early warning sign of an occult pancreatic tumor. Epidemiological studies show that individuals who develop diabetes after age 50 without an obvious cause such as obesity or family history are six to eight times more likely to have pancreatic cancer than the general population. A 2022 systematic review and meta-analysis refined this signal further: among new-onset diabetics, a family history of pancreatic cancer, a history of pancreatitis and rapid weight loss were the strongest predictors of an underlying malignancy within one year of the diabetes diagnosis. Risk prediction tools such as the ENDPAC score, which incorporates age, weight loss and changes in glycemic control, are now being used to decide which new diabetics should undergo pancreatic imaging. In structured screening programs that fast-track people aged 50 and older with new-onset or rapidly deteriorating diabetes to MRI-based surveillance, pancreatic cancer detection rates of approximately 0.9 percent have been reported, with screen-detected cases diagnosed at earlier stages than typically seen in sporadic presentations.

Chronic pancreatitis and pancreatic cystic lesions round out the high-risk landscape. Long-standing pancreatic inflammation raises cancer risk an estimated ten- to sixteen-fold, with the highest relative risk in the first few years after diagnosis, although guidelines from the American Gastroenterological Association and the US Preventive Services Task Force caution against blanket surveillance of all pancreatitis patients, reserving formal screening for hereditary cases and focused evaluation when new symptoms such as weight loss or jaundice appear. Cystic lesions, increasingly found incidentally on abdominal scans, present a different challenge. Main-duct and mixed-type intraductal papillary mucinous neoplasms carry a 50 to 60 percent chance of progressing to high-grade dysplasia or invasive cancer, while branch-duct lesions become concerning when they exceed three centimeters, harbor mural nodules or dilate the main pancreatic duct. Management follows the Fukuoka and AGA guidelines, with cyst fluid analysis—carcinoembryonic antigen levels above 192 nanograms per milliliter suggesting a mucinous origin, and KRAS, GNAS, TP53 and other mutations helping to grade malignant potential—guiding the choice between surgery and observation.

On the imaging front, a tiered approach has crystallized. MRI combined with MRCP, which offers high soft-tissue contrast without ionizing radiation, is the preferred modality for baseline and longitudinal surveillance, excelling at mapping ductal irregularities and characterizing cysts. Endoscopic ultrasound provides the highest spatial resolution and can detect tumors smaller than two centimeters that other methods miss; when combined with fine-needle aspiration it also enables cytological and molecular sampling, though its invasiveness, sedation requirement and small procedural risks reserve it for indeterminate findings. Pancreas-protocol computed tomography remains indispensable for staging and surgical planning but is less sensitive for small or cystic early lesions. PET-CT and the newer PET-MRI add metabolic information and are valuable for detecting occult metastases, but low fluorodeoxyglucose uptake in small tumors and false positives from inflammation currently limit their role in early detection, keeping them investigational for surveillance.

The most dynamic frontier lies in liquid biopsy—reading tumor signatures from blood, urine, saliva and stool. Circulating tumor DNA analysis can identify the mutations that define pancreatic cancer, including KRAS, present in 90 to 95 percent of tumors, along with TP53, CDKN2A and SMAD4, although the low abundance of tumor DNA shed by small tumors constrains sensitivity. Digital droplet PCR and next-generation sequencing are steadily improving detection. DNA methylation markers such as hypermethylated CDKN2A, SPARC, TFPI2 and NPTX2, detectable in plasma or pancreatic juice, show promising ability to distinguish cancer from pancreatitis. Protein panels are also advancing: combining TIMP1 and LRG1 with CA 19-9 pushed the area under the diagnostic curve above 0.9 in separating patients from controls, and a landmark 2018 study by Cohen and colleagues reported that a combined circulating tumor DNA and protein panel detected early-stage disease with 64 percent sensitivity and 99.5 percent specificity. Exosomes carrying glypican-1, a proteoglycan overexpressed on pancreatic cancer cells, have been isolated from patient serum with high sensitivity and specificity, even in early-stage disease, and their levels fall after surgical resection. Beyond blood, a urine panel of LYVE1, REG1A and TFF1 achieved an area under the curve of 0.89, rising to 0.94 when CA 19-9 was added, while stool-based assays hunting for KRAS mutations and cancer-associated gut microbiome signatures are being adapted from colorectal cancer screening.

Tying these molecular threads together is the emerging discipline of multi-omics integrated with artificial intelligence. Genomic, transcriptomic, proteomic and metabolomic data each capture a different layer of tumor biology—RNA sequencing of exosomes can reveal early epithelial-mesenchymal transition activity, microRNAs such as miR-21, miR-155 and miR-196a are overexpressed in early lesions, and a 2014 study in Nature showed that elevated branched-chain amino acids could predict pancreatic cancer up to two years before diagnosis. Machine learning models trained on such multi-layered datasets have achieved area-under-curve values exceeding 0.90 in distinguishing early cancer from benign disease. On the imaging side, deep learning convolutional networks applied to CT and MRI can flag subtle parenchymal changes and sub-2-centimeter lesions, in some cases matching or exceeding expert radiologists, while algorithms mining electronic health records can flag high-risk individuals six to twelve months before clinical diagnosis. The authors of the review caution that most of these tools remain investigational, evidence derives largely from high-risk cohorts, and precursor lesions are unpredictable in their progression, raising overdiagnosis concerns. Still, the trajectory is clear: by fusing clinical risk signals like new-onset diabetes with precision imaging, multi-omics biomarkers and AI-driven prediction, the field is assembling the toolkit it needs to move pancreatic cancer diagnosis from a race against time to a genuinely proactive, evidence-based enterprise.

Subject of Research: Early diagnosis strategies for pancreatic ductal adenocarcinoma, including risk stratification, imaging, biomarkers and artificial intelligence

Article Title: Strategy for early diagnosis of pancreatic cancer

Article References: Sharma, R. K., Singh, A., Sharma, G., Dawra, S., & Rana, S. S. (2026). Strategy for early diagnosis of pancreatic cancer. Frontiers in Gastroenterology, 5, Article 1731223. https://doi.org/10.3389/fgstr.2026.1731223

Image Credits: AI Generated

DOI: 10.3389/fgstr.2026.1731223

Keywords: pancreatic cancer, early diagnosis, PDAC, biomarkers, CA 19-9, liquid biopsy, circulating tumor DNA, new-onset diabetes, endoscopic ultrasound, MRI, artificial intelligence, multi-omics