A retrospective molecular epidemiological analysis of EML4-ALK gene fusions in non-small cell lung cancer patients in the Azerbaijani population (2014–2024)

Abstract Aim This retrospective molecular epidemiological study aimed to determine the prevalence, clinicopathological features, and survival outcomes of ALK gene fusions among patients with non-small cell lung cancer (NSCLC) in Azerbaijan, a country with limited access to molecular diagnostics and targeted therapy. Methods A total of 334 patients with histologically confirmed NSCLC diagnosed between 2014 and 2024 at the National Oncology Center were retrospectively analyzed. Formalin-fixed paraffin-embedded (FFPE) tumor tissues were tested using real-time polymerase chain reaction (RT-PCR) to detect EML4-ALK gene fusions. Clinical data, including demographics, histological subtype, TNM staging, lifestyle factors (tobacco and alcohol use), and geographical origin, were collected. Survival analysis was conducted using diagnosis and death dates, with censoring at July 1, 2025, for patients still alive. Descriptive statistics and Kaplan–Meier survival estimates were used. Results ALK gene fusions were identified in 6.6% ( n = 22) of NSCLC cases. The majority of ALK-positive patients were non-smokers and had adenocarcinoma histology (63.6%). The mean and median overall survival were 20.0 and 21.2 months, respectively. Most ALK-positive cases were located in the Baku–Absheron region, suggesting geographic disparities in molecular diagnostic access. Targeted therapy data were not available; however, anecdotal reports suggest limited access to ALK inhibitors such as crizotinib and alectinib, with ceritinib (Xalkori ® ) being the most accessible agent nationally. Conclusion The prevalence of ALK fusions among Azerbaijani NSCLC patients aligns with international data. Nevertheless, survival outcomes are suboptimal, likely due to delayed molecular testing and unequal access to targeted therapy. There is an urgent need to expand molecular diagnostic infrastructure and ensure broader availability of ALK inhibitors to improve clinical outcomes in this population.