The review, a narrative synthesis of published pharmacogenetic and pharmacokinetic studies, focused on germline polymorphisms—naturally occurring DNA sequence variants passed down in every cell—within three transporter genes of particular importance to oncology: ABCB1, ABCC1, and ABCG2. These genes encode efflux pumps that actively expel a wide range of chemotherapeutic agents and targeted therapies from cells. When a variant alters the pump’s activity, the same drug dose can produce very different concentrations inside tumors, bone marrow, the heart, or the nervous system, translating into differences in treatment response and side-effect severity.

ABCB1, also called P-glycoprotein, is the most intensively studied of the three. Encoded variants such as C1236T, G2677T/A, and C3435T have been examined extensively for their influence on taxanes, the drug class that includes paclitaxel and docetaxel, and on anthracyclines such as doxorubicin. These chemotherapies are substrates of the ABCB1 pump, meaning the transporter can shuttle them out of cells and limit their intracellular accumulation. Depending on which allelic combination a patient carries, pump activity may rise or fall, and the review documents associations between these variants and both toxicity profiles and treatment response in patients receiving taxane- and anthracycline-based regimens.

The clinical stakes are considerable. Taxanes and anthracyclines remain backbone therapies in breast cancer, lung cancer, ovarian cancer, lymphoma, and leukemia, among other malignancies. Their most feared toxicities—peripheral neuropathy that can persist for years, myelosuppression that leaves patients vulnerable to infection, and cardiotoxicity that can permanently weaken the heart muscle—are precisely the adverse events whose severity varies unpredictably between individuals. If transporter genotype contributes to that variability, as the reviewed evidence indicates, then a simple blood test performed before treatment could eventually help clinicians anticipate which patients need dose adjustments or intensified monitoring.

ABCC1, which encodes the multidrug resistance-associated protein 1, emerges in the review as a particularly consequential player in chemotherapy-induced harm. Variants in this gene have been linked to vincristine-induced peripheral neuropathy, a dose-limiting toxicity of a drug widely used in childhood leukemia and lymphoma protocols. Beyond neuropathy, ABCC1 polymorphisms have been associated with hematologic, gastrointestinal, hepatic, and cardiac toxicities following anthracyclines and other chemotherapy regimens, painting a picture of a transporter whose genetic configuration influences damage across multiple organ systems simultaneously.

ABCG2, the breast cancer resistance protein, takes center stage in the era of targeted therapy. Its C421A polymorphism, the most clinically notable variant highlighted in the review, has demonstrated associations with drug exposure and toxicity for selected tyrosine kinase inhibitors, the oral targeted agents that have transformed treatment of chronic myeloid leukemia and various solid tumors. Because ABCG2 normally restricts intestinal absorption and brain penetration of many kinase inhibitors, a reduced-function variant can raise plasma drug concentrations, increasing the likelihood of adverse events at standard doses. This mechanism offers a pharmacological explanation for why some patients on identical kinase inhibitor doses experience disproportionate toxicity.

The review situates these transporter findings within the broader architecture of precision oncology. Clinical pharmacogenetics has already secured a foothold through established biomarkers: DPYD genotyping to prevent fluoropyrimidine-induced severe toxicity, UGT1A1 testing to guide irinotecan dosing, and TPMT and NUDT15 screening to avert thiopurine-induced myelosuppression. These examples prove that germline genetics can be translated into actionable prescribing decisions. The authors argue that ABC transporter variants represent a potentially important additional factor contributing to variability in anticancer drug response, one that could complement the existing biomarker panel if validated prospectively.

Yet the review is candid about the obstacles standing between current evidence and clinical implementation. The findings across studies are heterogeneous, with different cohorts, cancer types, treatment regimens, and genotyping platforms producing inconsistent or even contradictory associations. The authors emphasize that transporter-mediated drug disposition is multifactorial: drug concentrations inside any given tissue reflect not only ABC pump genotype but also the activity of uptake transporters such as those in the SLC family, drug-metabolizing enzymes, tumor biology, renal and hepatic function, drug interactions, and patient characteristics such as age and comorbidities. A single variant studied in isolation will rarely capture this complexity.

That recognition shapes the review’s central recommendation for future research: the field should prioritize polygenic models that integrate pharmacogenomics with tumor- and patient-specific factors. Rather than asking whether one polymorphism predicts one toxicity, such models would combine multiple transporter variants with metabolizer genotypes, tumor molecular profiles, and clinical variables to build predictive algorithms capable of explaining a larger share of the observed variability in drug efficacy and toxicity. This systems-level approach mirrors the trajectory already seen in other areas of oncology, where multi-factor risk scores have outperformed single biomarkers.

For patients and clinicians, the message is one of cautious promise. ABC transporter pharmacogenetics is not yet ready for routine testing, but the accumulating associations between ABCB1 variants and taxane and anthracycline toxicity, ABCC1 variants and vincristine neuropathy, and ABCG2 C421A and kinase inhibitor exposure suggest a future in which transporter genotyping joins the standard pre-treatment workup. As larger, well-designed prospective studies accumulate, the humble cellular drug pumps that have long been studied for their role in multidrug resistance may find a second career as predictors of treatment success and sentinels against avoidable harm.

Subject of Research: Pharmacogenetics of ABC transporter polymorphisms in anticancer drug disposition, efficacy, and toxicity

Article Title: ABC transporter genetic polymorphisms in cancer therapy: implications for anticancer drug disposition, efficacy, and toxicity

Article References: Barrett, C., & Gálvez-Peralta, M. (2026). ABC transporter genetic polymorphisms in cancer therapy: implications for anticancer drug disposition, efficacy, and toxicity. Frontiers in Pharmacology, 17, Article 1966031. https://doi.org/10.3389/fphar.2026.1966031

Image Credits: AI Generated

DOI: 10.3389/fphar.2026.1966031

Keywords: ABC transporters, pharmacogenetics, ABCB1, ABCC1, ABCG2, chemotherapy toxicity, precision oncology, tyrosine kinase inhibitors, drug disposition, cancer therapy, transporter, genetic

The rationale for the biweekly approach is rooted in the realities of real-world oncology practice. In the pivotal trials that established GA as standard therapy, patients were carefully selected, often younger and fitter than the typical person who walks into a community cancer clinic. Once the regimen moved into routine care, clinicians observed that the three-doses-per-cycle schedule produced substantial hematologic toxicity, particularly neutropenia, as well as the peripheral neuropathy that is a signature adverse effect of the taxane class. These toxicities accumulate over successive cycles, and many patients end up receiving less drug than intended, potentially undermining the very efficacy that made the regimen attractive in the first place. The biweekly schedule was conceived as a way to give patients more recovery time between infusions, reducing the nadir burden and allowing fuller doses to be maintained over a longer treatment course.

To evaluate this strategy, the investigators conducted a comprehensive literature search across PubMed, Embase, Web of Science, Scopus, and the Cochrane Library, covering all records from database inception through February 2026 and following PRISMA reporting guidelines. They included both retrospective and prospective studies that compared biweekly GA with the standard weekly schedule in advanced or metastatic pancreatic ductal adenocarcinoma. Two reviewers independently carried out study selection, data extraction, and risk of bias assessment, with methodological quality evaluated using the ROBINS-I tool, which is designed specifically for non-randomized intervention studies. The primary outcomes of interest were overall survival and toxicity, while progression-free survival served as a secondary endpoint. Because the included studies differed substantially in design, populations, and reported parameters, the authors determined that a formal meta-analysis was not statistically appropriate, and they instead summarized their findings descriptively.

That search ultimately identified five retrospective studies meeting the inclusion criteria. In the studies that evaluated a standard-dose biweekly regimen, meaning gemcitabine at 1000 milligrams per square meter of body surface area and nab-paclitaxel at 125 milligrams per square meter, median overall survival ranged from 9.1 to 10 months, and median progression-free survival ranged from 4.8 to 5.4 months. These figures are strikingly consistent with historical benchmarks from the phase III MPACT trial, which established the weekly GA schedule, and with the control arm of the more recent NAPOLI 3 trial, which tested the NALIRIFOX regimen. In other words, cutting one infusion out of each 28-day cycle did not appear to cost patients meaningful survival time in these real-world cohorts, a finding that carries considerable practical weight for clinicians weighing tolerability against efficacy.

Not every dataset pointed in the same direction, however. One large population-based study of elderly patients, encompassing 1,303 individuals, reported a shorter median overall survival of 7.6 months with modified schedules. The authors of the review attribute this shortfall primarily to lower baseline performance status in that geriatric population rather than to the dosing interval itself, an important nuance that underscores how patient selection shapes outcomes in observational research. Elderly patients with advanced pancreatic cancer often present with comorbidities, frailty, and advanced disease burden that independently predict poorer survival, making direct comparisons with younger trial populations hazardous. This caveat is a recurring theme in real-world oncology evidence, and it highlights why the review’s authors call for prospective randomized trials before any definitive change to clinical guidelines.

Where the biweekly schedule truly distinguished itself was in its safety profile. Across the included studies, patients receiving GA on days 1 and 15 experienced lower rates of grade 3 or higher neutropenia, fewer episodes of febrile neutropenia, and less peripheral neuropathy compared with standard three-dose-per-cycle dosing. These are not trivial differences. Severe neutropenia exposes patients to potentially life-threatening infections and often triggers dose delays, while peripheral neuropathy is among the most feared and persistent toxicities of taxane-based therapy, capable of diminishing quality of life long after treatment ends. By extending the interval between infusions, the biweekly schedule appears to allow bone marrow recovery and nerve tissue respite, translating into fewer treatment interruptions and, plausibly, better adherence to the intended therapeutic course.

The technical logic behind this tolerability advantage is worth unpacking. Gemcitabine is a nucleoside analog that incorporates into replicating DNA and triggers masked chain termination, while nab-paclitaxel is an albumin-bound formulation of paclitaxel that stabilizes microtubules and blocks mitosis; the albumin carrier also exploits tumor vasculature to raise intratumoral drug concentrations. Both agents hit rapidly dividing compartments, and the bone marrow is among the most proliferatively active of these. Weekly dosing within a 28-day cycle means the marrow faces repeated insults with only seven days of recovery, and the nadir in neutrophil counts deepens with each successive exposure. A 14-day interval doubles that recovery window, allowing neutrophil counts to rebound more completely before the next challenge. For peripheral nerves, which have limited regenerative capacity, longer intervals may similarly reduce cumulative axonal injury, though the review’s descriptive nature means these mechanistic interpretations remain hypotheses rather than demonstrated mechanisms.

The review’s conclusions are deliberately measured. The authors state that biweekly GA appears to be a feasible and well-tolerated dosing strategy, with survival outcomes overlapping historical weekly GA cohorts in advanced or metastatic pancreatic ductal adenocarcinoma. They emphasize that while prospective randomized trials are needed, the reproducibility of both efficacy and tolerability findings across independent real-world cohorts supports biweekly GA as a viable alternative. That word, reproducibility, is central to the argument. A single retrospective study showing equivalent survival with fewer toxicities could be dismissed as chance or selection bias, but five separate cohorts converging on the same pattern, across different healthcare systems and patient populations, lends the finding a credibility that individual studies cannot achieve on their own.

For patients and clinicians, the practical implications are immediate even if the evidence remains observational. Advanced pancreatic cancer carries a median survival measured in months, and every week spent recovering from preventable toxicity is a week of diminished quality of life and potentially delayed subsequent therapy. If a biweekly schedule can deliver comparable survival with fewer hospitalizations for febrile neutropenia and less disabling neuropathy, it represents a meaningful improvement in the therapeutic ratio, achieved not with a new drug but with a smarter deployment of existing ones. Such schedule optimization is an underappreciated lever in oncology, often cheaper and faster to implement than drug development, though it requires the same rigorous testing standards.

The road ahead runs through prospective, randomized comparison. The review’s authors are explicit that their findings, however encouraging, cannot substitute for controlled evidence, and the heterogeneity that prevented meta-analysis also limits the precision of any single estimate. Still, the study offers a clear hypothesis for trialists to test: that in metastatic pancreatic ductal adenocarcinoma, gemcitabine plus nab-paclitaxel given biweekly at full doses can match the weekly schedule on survival while reducing grade 3 or higher neutropenia, febrile neutropenia, and peripheral neuropathy. If future randomized data confirm what these five real-world cohorts suggest, the standard of care for one of medicine’s most stubborn cancers could be refined not by adding a new agent, but by subtracting a dose, giving patients the same fight with a lighter burden to carry.

Subject of Research: Biweekly versus weekly gemcitabine plus nab-paclitaxel dosing for advanced pancreatic cancer

Article Title: Biweekly gemcitabine and nab-paclitaxel in advanced pancreatic cancer: a systematic review

Article References: Hoyek, C., Eslinger, C., Pirozzi, A., Zhu, M., Borad, M., Wu, C., Ahn, D., Bekaii-Saab, T., & Sonbol, M. B. (2026). Biweekly gemcitabine and nab-paclitaxel in advanced pancreatic cancer: a systematic review. BMC Cancer. https://doi.org/10.1186/s12885-026-17023-w

Image Credits: AI Generated

DOI: 10.1186/s12885-026-17023-w

Keywords: pancreatic cancer, gemcitabine, nab-paclitaxel, biweekly dosing, dose optimization, systematic review, metastatic pancreatic ductal adenocarcinoma, chemotherapy toxicity, neutropenia, peripheral neuropathy, overall survival, real-world evidence

The biological logic behind this approach begins with a phenomenon the authors call dysbiosis—a collapse of the gut’s normally diverse microbial community. Chemotherapy agents such as 5-fluorouracil, oxaliplatin, and cisplatin, the workhorses of gastric cancer regimens, do not discriminate neatly between tumor cells and the bacteria lining the intestine. The resulting microbial disruption damages the intestinal barrier, allowing bacterial components to leak into the bloodstream. Among these, lipopolysaccharide (LPS), a molecule embedded in the outer membrane of certain bacteria, is particularly consequential. Once LPS crosses a compromised gut wall, it binds to Toll-like receptor 4 (TLR4) on immune cells, triggering a signaling cascade through the transcription factor NF-κB and culminating in the activation of the NLRP3 inflammasome—a multiprotein molecular machine that ignites some of the body’s most potent inflammatory responses. The review identifies this LPS/TLR4/NF-κB/NLRP3 axis as a central driver of the systemic inflammation that underlies many chemotherapy side effects, from mucositis to immune dysfunction.

At the same time, chemotherapy starves the gut of one of its most valuable protective resources: short-chain fatty acids, or SCFAs. These small molecules—chiefly acetate, propionate, and butyrate—are produced by beneficial bacteria as they ferment dietary fiber. SCFAs are far more than metabolic waste; they act as signaling molecules and, remarkably, as inhibitors of histone deacetylases (HDACs), enzymes that control gene expression by chemically modifying chromatin. When SCFA levels fall, HDAC activity rises unchecked, anti-inflammatory gene programs are silenced, and the intestinal mucosa loses a critical shield against injury. Experimental work cited in the review shows that butyrate supplementation can prevent chemotherapy-induced gastrointestinal toxicity and microbial dysbiosis, while SCFA receptors such as GPR41, GPR43, and GPR109A on immune and epithelial cells mediate much of this protection. In other words, the difference between a tolerable chemotherapy course and a debilitating one may hinge, in part, on the metabolic output of a patient’s gut bacteria.

Against this mechanistic backdrop, the authors propose that TCM operates through what they term a structure–metabolite–immune framework. The idea is elegant in its simplicity: herbal compounds reshape the structure of the microbial community, the restructured community alters its production of metabolites, and those metabolites recalibrate the immune system. Restored microbial diversity means fewer LPS-producing pathogens and more SCFA-generating commensals. Lower LPS means less TLR4 activation; higher SCFAs means restored HDAC inhibition and calmer inflammatory signaling. The framework offers a unifying explanation for how wildly different herbal preparations—from complex multi-herb decoctions to single purified polysaccharides—can converge on similar protective outcomes. It also provides testable predictions: if the framework is correct, microbial sequencing and metabolite measurements should reveal consistent signatures in patients who respond well to TCM adjunct therapy.

The review catalogs a remarkable range of TCM components that fit this model. Polysaccharides from Astragalus membranaceus, a staple of Chinese herbal oncology, have been shown through multi-omics studies to protect against chemotherapeutic intestinal mucositis in animal models, and their structure–immunomodulation relationships are increasingly well mapped. Poria cocos polysaccharides exert a genuine prebiotic function, attenuating the adverse effects of 5-fluorouracil while improving its therapeutic outcome in mouse models of intestinal cancer. Polysaccharides from Atractylodes macrocephala protect against LPS-induced intestinal injury and appear to work partly by promoting gut bacterial production of tryptophan metabolites that activate the aryl hydrocarbon receptor, another key immunoregulatory pathway. On the flavonoid side, curcumin has been shown to suppress colorectal tumorigenesis partly by restoring gut microbiota and metabolites, while baicalin, derived from Scutellaria baicalensis, rebalances the regulatory T cell–Th17 axis and modulates SCFA profiles in models of colonic inflammation. Classical formulations such as Banxia Xiexin decoction and Shenling Baizhu powder have likewise been shown to reshape intestinal microbiota and SCFA metabolism in preclinical studies.

What elevates this review beyond a catalog of laboratory curiosities is its assessment of clinical evidence. The authors report that oral and injectable TCM formulations have accumulated moderate- to high-quality evidence for specific benefits in gastric cancer patients receiving chemotherapy. Shenqi Fuzheng injection (SFI), one of the most widely studied Chinese herbal injectables, has been the subject of multiple systematic reviews and meta-analyses showing improved immune function when combined with chemotherapy. Chinese herbal injections combined with SOX chemotherapy regimens—a common oxaliplatin plus S-1 protocol for advanced gastric cancer—have shown favorable effectiveness and safety profiles in Bayesian network meta-analyses. Oral preparations such as Shenqi Xiangyi granules have demonstrated benefits in advanced gastric cancer chemotherapy, and decoctions including Yipi Huayu and Zhipu Liujunzi have been associated in retrospective and propensity-matched studies with improved immune markers, favorable tumor marker trends, and reduced adverse reactions. The review also notes that these interventions appear to alleviate myelosuppression—the dangerous depletion of blood cell production in the bone marrow—and reduce gastrointestinal toxicities, two of the most clinically burdensome chemotherapy side effects.

The evidence is not uniformly strong, however, and the authors are candid about the gaps. External TCM therapies, including acupuncture and moxibustion, have generated some supportive data—a meta-analysis found benefits for gastrointestinal function and adverse events in gastric cancer patients after surgery and chemotherapy—but the overall quality of evidence for external approaches remains limited compared with oral and injectable formulations. Many of the most compelling mechanistic studies rely on animal models whose microbial and immune systems do not perfectly recapitulate human biology. Clinical trials are frequently small, single-center, and heterogeneous in their TCM preparations, dosing, and outcome measures, making it difficult to generalize. The review’s authors also point out that standard supportive care for chemotherapy toxicity—growth factors for neutropenia, antiemetic regimens for nausea—addresses symptoms rather than the underlying microbial and inflammatory mechanisms, leaving a genuine therapeutic vacuum that microbiota-targeted strategies could fill if properly validated.

Looking forward, the review charts several ambitious research frontiers. The authors highlight the STING signaling pathway—a DNA-sensing immune circuit with intimate connections to both inflammation and cell death—as an underexplored mechanistic link between microbial dysbiosis and chemotherapy toxicity. They similarly call for deeper investigation of the gut–brain axis, noting emerging evidence that chemotherapy-induced microbial disruption can exacerbate cancer-related fatigue through neuroimmune-endocrine signaling, and that interventions such as acupuncture and Lycium barbarum–probiotic combinations have shown promise in preclinical fatigue models by acting on this axis. Perhaps most consequentially, the authors advocate for large-scale randomized controlled trials and for the development of microbiota-based personalized TCM interventions—strategies in which a patient’s individual microbial profile would guide the selection of herbal therapy, much as tumor genomics guides targeted cancer drugs today. Such an approach would represent a genuine fusion of ancient pharmacopeia and modern precision medicine.

The implications extend well beyond gastric cancer. Dysbiosis has been implicated in chemotherapy-induced peripheral neuropathy, cardiotoxicity, and neurocognitive disorders, and microbial signatures of dysbiosis appear across gastrointestinal carcinogenesis. If the structure–metabolite–immune framework holds up under rigorous testing, microbiota modulation could become a standard pillar of supportive oncology care, alongside antiemetics and growth factors. For now, the review by Li and Ji stands as a careful synthesis of a rapidly maturing field—one that reframes chemotherapy toxicity not as an inevitable consequence of cancer treatment, but as a modifiable disorder of the gut ecosystem. The trillions of microbes that share our bodies, long overlooked in oncology, are emerging as both culprits and allies, and traditional Chinese medicine, whatever its ultimate clinical standing, has provided a rich and testable pharmacological toolkit for engaging them. The next decade of trials will determine whether this ancient-meets-modern strategy earns a permanent place in the cancer clinic.

Subject of Research: Gut microbiota modulation by traditional Chinese medicine to reduce chemotherapy-induced toxicity in gastric cancer

Article Title: Modulation of the gut microbiota by traditional Chinese medicine to attenuate chemotherapy-induced toxicity in gastric cancer: a review

Article References: Li, J., & Ji, F. (2026). Modulation of the gut microbiota by traditional Chinese medicine to attenuate chemotherapy-induced toxicity in gastric cancer: a review. Supportive Care in Cancer, 34(10), Article 1041. https://doi.org/10.1007/s00520-026-11290-w

Image Credits: AI Generated

DOI: 10.1007/s00520-026-11290-w

Keywords: gastric cancer, chemotherapy toxicity, gut microbiota, traditional Chinese medicine, short-chain fatty acids, LPS, TLR4, NF-κB, NLRP3 inflammasome, dysbiosis, polysaccharides, integrative oncology

The research drew on the Geriatric Assessment for Patients (GAP70+) study, a multicentre, cluster-randomized clinical trial conducted across 39 community oncology clinics affiliated with the University of Rochester Cancer Center NCI Community Oncology Research Program Research Base. Participants were aged 70 or older, had incurable stage III or IV solid tumours or lymphoma, and were scheduled to begin a new systemic treatment regimen known to carry a high risk of toxicity. From the trial’s usual care arm, the investigators collected abdominal and pelvic CT or PET/CT scans performed as part of routine care, applying strict time windows around enrollment and rigorous quality control. That process yielded 161 patients whose imaging and clinical data could be fully analysed, with a mean age of 76.6 years, nearly 61 percent male, and most carrying gastrointestinal or lung cancers.

What sets this analysis apart from the bulk of prior sarcopenia research in oncology is its adherence to a full clinical definition of the condition rather than a single imaging measurement. The European Working Group on Sarcopenia in Older People, known as EWGSOP2, defines sarcopenia using three criteria: reduced muscle strength, reduced muscle quantity and quality, and reduced physical performance. In this study, strength was assessed with a five-time chair-stand test, where a time exceeding 16.7 seconds signalled weakness. Muscle quantity was quantified from the mid-L3 lumbar vertebra slice of each CT scan using validated automatic segmentation software, producing a skeletal muscle index with sex- and BMI-specific thresholds. Muscle quality was captured through Hounsfield Unit measures of tissue density on the same scans, and physical performance was evaluated with the timed up-and-go test. Meeting the strength and quantity or quality criteria classified a patient as sarcopenic; meeting all three criteria indicated severe sarcopenia.

The prevalence figures were sobering. More than two-thirds of participants, 68.3 percent, had low muscle quantity by imaging criteria, and 56.5 percent met the full clinical definition of sarcopenia. Among those, 59 percent were classified as having severe sarcopenia. Patients with sarcopenia were on average about two years older than those without it and were significantly more likely to have diabetes. More tellingly, sarcopenia tracked closely with broader geriatric vulnerability: those with the severe form were significantly more likely to show impaired nutrition, dependence in activities of daily living and instrumental activities, recent falls and impaired cognition compared with patients whose muscles were preserved. In other words, the clinical sarcopenia label captured a constellation of ageing-related frailty that a simple muscle measurement did not.

When the researchers turned to treatment outcomes, documented through clinician-reported adverse events graded with the Common Terminology Criteria for Adverse Events, version 4.0, a nuanced picture emerged. Overall severe toxicity, defined as Grades 3 through 5, during the first three months of therapy did not differ significantly between patients with and without sarcopenia. But severe nonhematologic toxicities—a category that includes complications such as dehydration, electrolyte disturbances, infections, fatigue and pain, which frequently lead to hospitalization—were substantially more common in the sarcopenic group, affecting 64 percent versus 44 percent. In multivariable logistic regression adjusting for age, tumour site, sex, comorbidities and treatment type, sarcopenia more than doubled the odds of severe nonhematologic toxicity, with an odds ratio of 2.24. Notably, patients who suffered these severe nonhematologic events also had significantly slower chair-stand times, and each additional second on that strength test raised the odds of toxicity by roughly 15 percent.

The mortality findings were even more striking. At one year, only 46 percent of participants with sarcopenia were alive, compared with 60 percent of those without it. After statistical adjustment this difference fell just short of significance in the full cohort, but when the analysis focused on patients starting first-line chemotherapy, sarcopenia was clearly associated with poorer survival, with a hazard ratio of 2.12. For severe sarcopenia the signal was unmistakable: one-year survival was just 40 percent versus 60 percent among patients without sarcopenia, a difference that remained significant after adjustment with a hazard ratio of 2.08. The mortality gap opened early—within three months, nearly 21 percent of patients with severe sarcopenia had died, versus 7 percent of those without the condition. Crucially, when the investigators evaluated skeletal muscle index alone, stripped of the strength and performance components, no significant association with survival appeared at all.

That last result may be the study’s most important technical message. Much of the oncology literature has equated sarcopenia with low muscle quantity on imaging, treating the skeletal muscle index as a standalone prognostic marker. This analysis suggests that in older adults that approach is insufficient, because muscle mass declines physiologically with age and is not a linear proxy for what muscles can actually do. The consensus definitions that incorporate grip-equivalent strength measures and performance tests appear to identify a genuinely distinct population of patients whose functional reserve is depleted and who are therefore less able to withstand the catabolic assault of cytotoxic therapy. The authors note this contrasts with patterns seen in younger patients, in whom imaging-based muscle measures have shown stronger associations with outcomes.

The comparison with the limited prior work reinforces the point. Only one earlier study, in men with metastatic castrate-resistant prostate cancer, had evaluated treatment toxicity in older adults using a definition of sarcopenia encompassing strength, quantity and performance; it reported a prevalence of 27 percent, lower than the 57 percent seen here, likely reflecting stricter criteria that resemble the severe sarcopenia category. That study likewise linked sarcopenia to poorer survival and heightened toxicity risk. Two recent studies in gastrointestinal cancer patients that relied on muscle index alone produced inconsistent survival associations, underscoring the value of the multi-domain approach. The new analysis also benefits from real-world breadth: patients were treated in community clinics nationwide rather than tertiary referral centres, and toxicity data met the annotation standards of a randomized trial.

The limitations are worth noting. The cohort was predominantly non-Hispanic white, limiting generalizability to other populations. Scans were not mandated by the protocol, and the strict time windows that ensured data quality reduced the analysable sample. As an exploratory secondary analysis, p-values were not corrected for multiple testing, so the findings are hypothesis-generating and require confirmation in prospective cohorts. Treatment regimens and dosing were left to each patient’s oncologist rather than standardized. Even so, the clinical implications are hard to dismiss. Patients with severe sarcopenia received some of the most intensive treatments in the cohort yet had the worst survival, raising the possibility of overtreatment and suggesting that comprehensive geriatric evaluation should precede decisions about aggressive therapy.

The authors argue that sarcopenia screening should become routine in geriatric oncology, and they point to a practical path. Although CT scans are already available for nearly every cancer patient and software tools exist to quantify muscle from them, the expertise to interpret such measurements is not yet part of routine practice. The geriatric assessment, by contrast, is already recommended by ASCO guidelines and captures exactly the measures—chair-stand strength, timed up-and-go performance, falls, daily functioning—that this study linked to toxicity and death. Integrating those simple tests into treatment planning, and designing intervention trials that incorporate sarcopenia status into treatment selection and dosing, could spare the most vulnerable older adults the cruelest harms of therapy while preserving its benefits for those robust enough to tolerate it.

Subject of Research: Sarcopenia and treatment toxicity and mortality in older adults with advanced cancer

Article Title: Sarcopenia Is Associated With Severe Treatment Toxicity and Mortality in Older Adults With Advanced Cancer: A Secondary Analysis

Article References: Mattick, L. J., Mohammed, M., Li, C.-S., Tylock, R. G., Loh, K. P., Flannery, M. A., Peppone, L. J., Lin, P.-J., Goncalves, M. D., Caan, B. J., Cespedes Feliciano, E. M., Popuri, K., Beg, M. F., Bearden, J. D., Berenberg, J., Katato, K., Mustian, K. M., Mohile, S. G., & Dunne, R. F. (2026). Sarcopenia Is Associated With Severe Treatment Toxicity and Mortality in Older Adults With Advanced Cancer: A Secondary Analysis. Journal of Cachexia, Sarcopenia and Muscle, 17(5), Article e70388. https://doi.org/10.1002/jcsm.70388

Image Credits: AI Generated

DOI: 10.1002/jcsm.70388

Keywords: sarcopenia, geriatric oncology, advanced cancer, chemotherapy toxicity, muscle strength, mortality, CT body composition, EWGSOP2, geriatric assessment, cancer cachexia, older adults, clinical trial

CTIT is a common and clinically consequential hematologic toxicity in patients with solid tumors. Chemotherapy, radiotherapy, and targeted agents can all suppress the bone marrow’s ability to produce platelets, the small cell fragments that form clots and prevent hemorrhage. When platelet counts fall below safe thresholds, oncologists are frequently forced to postpone or reduce doses of anti-cancer drugs, compromising the very treatment meant to control the tumor. In severe cases, spontaneous bleeding can become life-threatening. Platelet transfusions and standard TPO-RA monotherapy help many patients, but a subset remains refractory, with counts that stay dangerously low despite every conventional measure.

The research team, led by Lin-Ya Wang and Fei-Fei Tang of the Peking University Institute of Hematology, set out to test whether adding ATRA to continued TPO-RA therapy could break through this resistance. Their rationale rests on platelet biology: TPO-RAs such as eltrombopag and romiplostim stimulate thrombopoietin receptors on megakaryocytes, the large bone marrow cells that shed platelets into the bloodstream, while ATRA is thought to promote megakaryocyte maturation and platelet production through complementary pathways, including retinoid signaling and effects on the bone marrow microenvironment. Combining the two agents, the investigators reasoned, might attack the problem from two directions at once.

The study retrospectively analyzed 28 patients with refractory CTIT, defined as grade 2 or worse thrombocytopenia according to the CTCAE v5.0 criteria despite prior TPO-RA therapy. All patients were treated at Peking University People’s Hospital between August 2023 and May 2025. Each received oral ATRA at a dose of 25 milligrams per square meter of body surface area daily for six weeks, alongside continued TPO-RA treatment. The severity of the starting condition was sobering: the median baseline platelet count was just 13 × 10⁹ per liter, with individual values ranging from a perilous 2 × 10⁹ to 69 × 10⁹ per liter. Counts at that level leave patients exposed to serious bleeding risk and effectively rule out continued cancer therapy.

The results were unambiguous. Platelet counts climbed steadily from baseline after treatment began, with median elevations of +17 × 10⁹ per liter by day 14 (P = 3.05 × 10⁻⁵), +36 × 10⁹ per liter by day 28 (P = 9.54 × 10⁻⁷), and +59 × 10⁹ per liter by day 42 (P = 7.45 × 10⁻⁹). By the end of the observation window, the median patient had gained nearly five times their starting platelet count. Twelve patients, or 42.9 percent, achieved a complete response, defined as recovery to normal platelet levels, while another seven patients, 25.0 percent, achieved a partial response. The overall response rate stood at 67.9 percent, meaning roughly two of every three patients who had failed standard therapy regained usable platelet counts. The median time to complete response was 31 days, with responses occurring as early as 12 days and as late as 40 days after starting the combination.

Safety data were equally encouraging. ATRA is not a benign molecule; it carries known risks of liver enzyme elevation, headache, and, in the setting of acute promyelocytic leukemia, a potentially dangerous complication called differentiation syndrome. Yet in this population, the combination was well tolerated. Only four patients, 14.3 percent, developed elevated liver enzymes, three of them grade 1 and one grade 2, and three patients, 10.7 percent, experienced mild, grade 1 nausea. Critically, no grade 3 or higher adverse events were recorded, no thrombotic events occurred, and no patient developed differentiation syndrome. For a drug that stimulates platelet production, the absence of clotting complications is a particularly important signal, since raising platelet counts in cancer patients could theoretically tip the balance toward thrombosis.

The study also uncovered intriguing patterns in who responded best. Within the female cohort, patients with tumors of the female reproductive system responded significantly more poorly than those with other cancers: their overall response rate was 57.1 percent compared with 100.0 percent for non-FRS tumors (P = 0.038), and none of the FRS tumor patients achieved a complete response versus 70.0 percent of the others (P = 0.008). The authors also noted trends toward inferior complete response rates among patients with a history of radiotherapy (P = 0.057) and those treated with paclitaxel (P = 0.054), neither of which reached statistical significance in this small sample. These signals suggest that the biology of refractory CTIT may differ depending on the tumor type and prior treatment exposures, and that certain patient groups may need alternative or intensified strategies.

One of the most mechanistically revealing findings involved the bone marrow itself. Patients whose baseline bone marrow biopsies showed higher megakaryocyte counts, at least five per high-powered field, exhibited a trend toward higher overall response rates compared with those with lower counts, 76.5 percent versus 54.5 percent, though the difference did not reach statistical significance (P = 0.41). The observation makes biological sense: megakaryocytes are the cellular factories of platelets, and a marrow that retains a reasonable supply of these cells is more likely to respond to drugs that push them into overdrive. Conversely, patients whose marrows have been devastated by chemotherapy or radiotherapy may lack the raw cellular substrate needed for any platelet-boosting strategy to succeed. If confirmed in larger cohorts, megakaryocyte counts could help clinicians identify which refractory patients are most likely to benefit from the ATRA-plus-TPO-RA combination before committing to six weeks of therapy.

The study’s design demands careful interpretation. As a retrospective, single-center analysis of 28 patients, it cannot rule out selection bias, and without a randomized control group it is impossible to say with certainty how many patients would have recovered on continued TPO-RA monotherapy alone. The authors themselves frame the work as hypothesis-generating. Nevertheless, the magnitude and tempo of the platelet recoveries, the near-complete absence of serious toxicity, and the internal consistency of the response kinetics give the findings considerable weight. A prospective randomized trial will be needed before the combination can be recommended as standard of care, but for a population with essentially no good options, the bar for moving forward is low.

The broader significance extends beyond one drug pairing. CTIT is becoming an increasingly visible problem as cancer therapy grows more intensive and as patients live longer with advanced disease, and refractory cases consume transfusion resources while delaying tumor-directed treatment. The Peking University study suggests that rational combinations of agents targeting different nodes of thrombopoiesis, in this case retinoid-driven megakaryocyte maturation layered on top of thrombopoietin receptor stimulation, can rescue patients who were previously written off. It also revives interest in ATRA, a decades-old leukemia drug, as a repurposed agent in supportive oncology. If larger trials confirm these results, a cheap oral vitamin A derivative could become a standard partner for platelet-boosting drugs, keeping cancer treatment on schedule for thousands of patients whose platelets, and whose therapies, currently run out of road.

Subject of Research: Combination therapy with all-trans retinoic acid and thrombopoietin receptor agonists for refractory cancer therapy-induced thrombocytopenia

Article Title: All-trans retinoic acid combined with thrombopoietin receptor agonists for refractory cancer therapy-induced thrombocytopenia: a retrospective single-center study

Article References: Wang, L.-Y., Gao, H.-T., Fu, Q., Xu, L.-P., Zhang, X.-H., Huang, X.-J., & Tang, F.-F. (2026). All-trans retinoic acid combined with thrombopoietin receptor agonists for refractory cancer therapy-induced thrombocytopenia: a retrospective single-center study. Annals of Hematology. https://doi.org/10.1007/s00277-026-07287-4

Image Credits: AI Generated

DOI: 10.1007/s00277-026-07287-4

Keywords: all-trans retinoic acid, thrombopoietin receptor agonists, cancer therapy-induced thrombocytopenia, platelets, megakaryocytes, solid tumors, hematology, chemotherapy toxicity, Peking University, retrospective study, thrombopoiesis, drug safety

The scale of the problem is considerable. Breast cancer accounted for approximately 2.308 million new cases worldwide in 2022, representing 11.6 percent of all new cancer diagnoses and making it the second most common cancer globally. Chemotherapy remains a cornerstone of treatment for early-stage disease, but its toxicities—ranging from severe neutropenia to peripheral neuropathy—can force dose reductions, treatment interruptions, or complete discontinuation, ultimately compromising prognosis and quality of life.

The review, led by researchers at The First Affiliated Hospital of Jinzhou Medical University in China, synthesizes evidence on how body composition indicators relate to chemotherapy toxicity. The authors trace the evolution of assessment methods from crude anthropometric surrogates—such as the five percent weight-loss threshold once used to mark cachexia in the 1970s—to today’s sophisticated imaging tools. Computed tomography, magnetic resonance imaging, dual-energy X-ray absorptiometry (DXA), and bioelectrical impedance analysis (BIA) now allow clinicians to quantify skeletal muscle, visceral fat, subcutaneous fat, and muscle quality with remarkable precision, and artificial intelligence is increasingly automating these analyses.

Central to the discussion is the distinction between lean body mass and fat-free mass, terms that are chemically similar but historically defined differently—lean body mass includes polar lipids, while fat-free mass does not. The authors recommend prioritizing fat-free mass in research to improve scientific rigor. They also highlight the third lumbar vertebra skeletal muscle index (L3-SMI), calculated from a single CT slice as skeletal muscle area at L3 divided by height squared, which was first reported in 2008 as an independent predictor of chemotherapy toxicity. Notably, DXA-derived appendicular lean mass indices and CT-based L3-SMI correlate only moderately (r = 0.66, p < 0.001), meaning the two metrics are not directly interchangeable—a source of ongoing confusion in the literature.

The mechanistic story is where the review becomes particularly compelling. Muscle is highly vascularized and metabolically active, so patients with greater lean mass tend to metabolize and clear drugs more efficiently. Pharmacokinetic studies bear this out: each additional kilogram of lean body mass increased doxorubicin clearance by roughly 19 percent in an exploratory study, and lower muscle mass was associated with reduced volume of distribution and higher peak plasma concentrations of paclitaxel. Low lean mass can also reduce creatinine production, causing the Cockcroft-Gault formula to overestimate renal function—a hazard flagged by a creatinine clearance to glomerular filtration rate ratio of 1.23 as a warning threshold for carboplatin overdose and severe thrombocytopenia.

Fat tells a different, sometimes paradoxical story. Lipophilic agents such as paclitaxel and docetaxel distribute into adipose compartments, while hydrophilic drugs like fluoruracil and cyclophosphamide prefer water-rich lean tissue. Visceral fat volume was positively correlated with doxorubicin exposure (r² = 0.324, P < 0.001) and grade 4 leukopenia in Asian breast cancer patients. Experimental work suggests adipocytes can increase anthracycline levels by 30 percent by upregulating CBR1 and AKR metabolic enzymes, sustaining the release of toxic metabolites. Visceral fat-derived free fatty acids also reach the liver through the portal circulation, potentially inducing hepatic steatosis and impairing drug metabolism—liver attenuation on CT, inversely related to fat content, predicted epirubicin exposure in one analysis.

The clinical correlations are striking. In early-stage breast cancer patients, higher fat mass increased the risk of toxicity-induced modification of treatment—dose reductions, interruptions, cessation, or regimen changes—while higher relative lean mass reduced that risk. Obese patients (BMI ≥ 30 kg/m²) experienced docetaxel dose reductions at 18 percent versus 5 percent in nonobese patients (p = 0.008), along with lower pathological complete response rates and shorter disease-free survival. Sarcopenia, which affects an estimated 40 to 45 percent of breast cancer patients, independently predicted severe toxicity: sarcopenic patients receiving epirubicin-cyclophosphamide experienced severe laboratory adverse events at 70 percent versus 22.2 percent (OR 7.9, p = 0.004). Myosteatosis—fat infiltration within muscle, visible as lower Hounsfield units on CT—was associated with reduced relative dose intensity and with dose reductions, early treatment interruption, and hospitalization.

Perhaps the most alarming phenotype is sarcopenic obesity, the coexistence of excessive adiposity with reduced muscle mass and impaired function, as defined by the ESPEN-EASO consensus. In early-stage breast cancer patients receiving anthracycline and taxane chemotherapy, sarcopenic obesity independently predicted severe toxicity, tripling the risk of grade 3–4 hematological toxicity and raising the risk of neutropenia 3.5-fold. Prevalence estimates vary widely—from 0.8 to 22.3 percent in general populations—partly because diagnostic thresholds remain inconsistent, with more than 14 sarcopenia cutoffs reported across oncology studies.

The review does not shy away from the field’s contradictions. Adipose tissue can exert bidirectional effects: in one study of 120 patients receiving neoadjuvant chemotherapy, higher fat percentage correlated with reduced neurotoxicity risk, though no significant interaction appeared in platinum-containing regimens. Chemotherapy itself alters body composition over time, and most studies rely only on baseline measurements, potentially underestimating true toxicity risk. The authors also point to the LEANOX randomized controlled trial as proof of concept: lean body mass-based oxaliplatin dosing at 3.09 mg/kg increased the proportion of patients free of grade ≥ 2 peripheral neurotoxicity from 42.1 to 67.2 percent, without compromising long-term survival—evidence that composition-guided dosing is clinically practicable, at least for some drugs.

Looking forward, the authors call for regimen-specific pharmacokinetic modeling across anthracyclines, taxanes, and platinum agents; risk stratification that integrates breast cancer subtypes with visceral-to-subcutaneous fat ratios and muscle indices; prospective trials of nutritional optimization and resistance training in high-risk patients; and international consensus on definitions and cutoffs, potentially enriched with multi-omics biomarkers. They suggest DXA, a low-radiation whole-body scan, could eventually replace CT for routine body composition assessment in early cancer, where L3-level CT scans are not standard. Until prospective, breast cancer-specific studies validate these approaches, body surface area dosing will remain the norm—but the writing is on the wall, and it is written in muscle and fat.

Subject of Research: The relationship between body composition and chemotherapy-related toxicity in early-stage breast cancer

Article Title: Body composition and chemotherapy-related toxicities in early-stage breast cancer: implications for personalized treatment strategies

Article References: Tang, X., Wang, J., Feng, D., Tian, Y., Zhang, X., Zhang, M., Zhang, Y., Yang, B., Zhou, X., Zhao, J., Tao, W., Liu, Y., & Zhai, Z. (2026). Body composition and chemotherapy-related toxicities in early-stage breast cancer: implications for personalized treatment strategies. Holistic Integrative Oncology, 5(1), Article 69. https://doi.org/10.1007/s44178-026-00287-4

Image Credits: AI Generated

DOI: 10.1007/s44178-026-00287-4

Keywords: breast cancer, body composition, chemotherapy toxicity, sarcopenia, sarcopenic obesity, lean body mass, visceral fat, myosteatosis, pharmacokinetics, personalized dosing, DXA, CT imaging