Prevalence of EGFR and ALK Mutations in Lung Adenocarcinomas in the Levant Area - a Prospective Analysis.

Background: A significant percentage of lung adenocarcinomas have a driver mutation. To date, there has been no assessment of the prevalence of such mutations in a Middle Eastern population. The present multicenter prospective study of formalin fixed paraffin embedded (FFPE) tissues from patients diagnosed with lung adenocarcinoma was performed to assess the prevalence of EGFR and ALK mutations in the Levant. Methods: Patients of Middle Eastern origin with lung adenocarcinomas at 10 sites in Lebanon, Jordan and Iraq were prospectively enrolled. Tumors were tested for EGFR by PCR and for EML4-ALK translocation by fluorescence in situ hybridization (FISH). Results: A total of 210 patients were enrolled, 139 (66.2%) males and 71 females (33.8%), with a mean age of 63.4 years. EGFR testing of 205 (97.6%) demonstrated the wild type in 173 (84.4%) and mutated forms in 32 (15.6%). Some 46.9% of EGFR positive patients were non-smokers and 62.5% were females as opposed to 22.4% and 33.8%, respectively, in the general population. As for the EML4-ALK translocation, testing in 157 (74.8%) cases gave negative results in 154 (98.1%) , only 3 being positive (1.9%), 2 being females and 2 non-smokers.Conclusion: Our study established a 15.6% EGFR mutation rate in lung adenocarcinomas with ALK translocation mutations in only 1.9%, as compared to a 15-20% and 5%, respectively, in the Western literature.