Massive Turkish Genome Study Maps Hidden Mutation Patterns in Advanced Lung Cancer

One of the largest real-world genomic surveys of lung cancer ever conducted has delivered a strikingly detailed portrait of how tumors in patients with advanced non-small cell lung cancer (NSCLC) are wired at the DNA level. Researchers at Gazi University in Ankara analyzed tumor tissue and blood plasma from 1,500 patients using targeted DNA-based next-generation sequencing (NGS), and their findings, published in BMC Cancer, reveal both the dominant genetic drivers of the disease and the subtle co-mutation patterns that could shape how doctors select therapies in the clinic. The study, led by pathologists Aysu Sadioglu, Ozgur Ekinci, and Nalan Akyurek, offers one of the most comprehensive molecular maps of NSCLC in a Turkish population to date, and it underscores how much clinically meaningful information can be extracted from routine diagnostic samples when modern sequencing technology is applied at scale.

The technical backbone of the study was a targeted NGS workflow built on QIAGEN GeneReader panels, run on formalin-fixed, paraffin-embedded (FFPE) tissue as well as plasma samples. This is the material that pathology laboratories already produce every day, which makes the approach directly translatable to real-world practice rather than confined to specialized research cohorts. The team evaluated three classes of genomic alterations: single nucleotide variants (SNVs), which are single-letter changes in the DNA code; insertions and deletions (indels), which add or remove letters; and copy number variations (CNVs), which duplicate or delete larger stretches of the genome. Associations between these alterations and clinicopathological features such as sex, smoking status, and histological subtype were then analyzed statistically, providing a layered picture of how genomic profiles vary across patient groups.

The headline result concerns the two most notorious oncogenes in lung cancer. Alterations in EGFR, the epidermal growth factor receptor, were detected in 23.7 percent of patients, while KRAS mutations appeared in 22.5 percent. These two genes, which sit at the top of critical cell-signaling pathways controlling growth and division, together accounted for nearly half of the actionable genomic landscape in this cohort. Behind them, the team identified recurrent alterations in MET, STK11, PIK3CA, and FGFR1, each of which carries its own therapeutic implications. MET amplification and mutation can sensitize tumors to MET inhibitors, STK11 loss is increasingly recognized as a marker of immunotherapy resistance, PIK3CA alterations point to PI3K-pathway dependencies, and FGFR1 amplification has been explored as a target in squamous tumors.

One of the most clinically significant technical details in the study involves EGFR amplification, which was detected in 12.1 percent of patients and frequently co-occurred with EGFR mutations. This matters because EGFR copy number gain on top of an activating mutation may influence both tumor biology and treatment response, particularly in the context of tyrosine kinase inhibitors (TKIs), the targeted drugs that block EGFR signaling. The predominant EGFR mutations were exon 19 deletions and L858R substitutions, the two classic sensitizing alterations that predict strong responses to first- and later-generation EGFR TKIs. On the KRAS side, the G12C variant was the most common, and this is a particularly notable finding because KRAS G12C has recently become directly druggable with a new class of covalent inhibitors, transforming what was once considered an undruggable mutation into one of the hottest targets in thoracic oncology.

The study also revealed clear sex-based differences in the genomic landscape. EGFR alterations and ERBB2 (HER2) mutations were more common in female patients, whereas KRAS, FGFR1, and MET alterations were more frequent in male patients. These patterns align with well-established epidemiological trends, in which EGFR-mutant lung adenocarcinoma is more prevalent in women and in lighter or never-smokers, while KRAS-mutant tumors correlate more strongly with smoking exposure. But the fact that these differences hold up in a large Turkish cohort adds population-specific weight to the observation and reinforces the argument that molecular testing should be applied broadly rather than restricted by assumptions about who is likely to harbor which driver.

Perhaps the most scientifically intriguing aspect of the work is its characterization of co-mutation patterns, the combinations of alterations that appear together within the same tumor. EGFR and KRAS alterations demonstrated a largely mutually exclusive pattern, meaning tumors almost never carried activating mutations in both genes at once. This is consistent with the biology of these pathways, since constitutive activation of one driver typically removes the selective pressure for activating the other. In contrast, KRAS commonly co-occurred with STK11 and PIK3CA alterations, a combination that has been linked in prior studies to more aggressive disease biology and reduced benefit from immune checkpoint inhibitors when STK11 is lost. These co-alteration signatures are not merely descriptive; they carry direct implications for prognosis, immunotherapy response, and the design of rational combination therapies.

The team also observed distinct genomic profiles across histological subtypes, meaning that adenocarcinomas, squamous cell carcinomas, and NSCLC not otherwise specified each carried their own characteristic alteration patterns. This reinforces the argument that comprehensive molecular profiling should be performed on every NSCLC patient regardless of subtype, rather than reserving broad panels for adenocarcinoma alone. Squamous tumors, which have historically had fewer actionable targets, may still harbor alterations in FGFR1, PIK3CA, or MET that could open doors to targeted trials or therapies. The study’s real-world design, drawing on routine diagnostic samples rather than a curated clinical trial population, makes these subtype-specific patterns particularly relevant to everyday practice.

Technically, the study relied on DNA-based sequencing, which captures SNVs, indels, and CNVs but does not directly detect gene fusions such as ALK, ROS1, or NTRK rearrangements, which typically require RNA-based or fusion-specific assays. This is an important caveat when interpreting the results, since fusions represent another major class of actionable drivers in NSCLC. The authors’ focus on DNA-based panels reflects the reality of many molecular pathology laboratories, where DNA sequencing is often the first and most accessible NGS platform. The findings therefore highlight both the power and the boundaries of DNA-only profiling, and they suggest that optimal molecular assessment may require combining DNA-based panels with complementary assays for fusions and other rearrangements.

The broader significance of the study lies in its scale and its population. Most large genomic datasets in NSCLC come from North American, European, or East Asian cohorts, and population-specific factors can influence both the prevalence of certain mutations and the interpretation of co-mutation patterns. By generating one of the largest Turkish NSCLC genomic datasets to date, the team has filled a meaningful gap in the global molecular map of lung cancer. The work also demonstrates the value of retrospective real-world studies, which can capture the heterogeneity of patients seen in routine clinical practice, including those with comorbidities, unusual histologies, or atypical treatment histories who are often underrepresented in prospective trials.

For clinicians, the study reinforces the argument that comprehensive NGS profiling should be standard of care in advanced NSCLC, not an optional extra. The identification of recurrent co-alteration patterns involving EGFR, KRAS, STK11, MET, and PIK3CA provides a framework for thinking about tumor biology in a more integrated way, moving beyond single-gene testing toward a holistic view of the genomic landscape. As targeted therapies and immunotherapies continue to expand, the ability to read a tumor’s full genomic signature, including the alterations that travel together, will become increasingly central to selecting the right treatment for the right patient. This study, grounded in real-world samples from a large Turkish cohort, adds both technical depth and population-specific evidence to that evolving paradigm.

Subject of Research: Lung cancer genomics

Article Title: Genomic alterations and co-mutation patterns in advanced NSCLC: a real-world DNA-based NGS study in a large Turkish cohort

Article References: Sadioglu, A., Ekinci, O., & Akyurek, N. (2026). Genomic alterations and co-mutation patterns in advanced NSCLC: a real-world DNA-based NGS study in a large Turkish cohort. BMC Cancer. https://doi.org/10.1186/s12885-026-16949-5

Image Credits: AI Generated

DOI: 10.1186/s12885-026-16949-5

Keywords: NSCLC, next-generation sequencing, EGFR, KRAS, STK11, MET, PIK3CA, co-mutation, lung cancer, genomic profiling, Genomic, alterations