The prevalence of ALK rearrangement in pulmonary adenocarcinomas in an unselected Caucasian population from a defined catchment area; impact of smoking

摘要: Aims To assess the prevalence of EML4–ALK rearrangement gene measured by immunohistochemistry in an unselected population-based consecutive cohort patients with adenocarcinoma lung (ACL), and correlation smoking history, thyroid transcription factor 1 (TTF1), gender age. Methods results All diagnosed population greater Copenhagen area were included, irrespective gender, age, habits, stage or type available diagnostic material. Tumours stained (clone 5A4). Immunohistochemistry-positive tumours tested fluorescence in-situ hybridization (FISH). During a 16-month period, 760 ACL. In 2.6% there was insufficient material for ALK testing (20 760). Eleven per cent remaining 740 ACL never smokers, 43% ex-smokers smokers 46% current smokers. Fourteen [1.9%, 95% confidence interval (CI) = 1.1–3.2] ALK-positive immunohistochemistry. Nine 82 never-smokers (11%, CI 5.9–19.6) five 652 ex- (0.8%, 0.4–2.1) ALK-positive. Only two found among 586 heavy (> 15 pack-years) (0.3%, 0.09–1.2). Thirteen 14 immunohistochemistry-positive FISH-positive. All TTF1-positive. The number needed to test (NNT) identify one positive patient 9, 22 293 light respectively. Conclusions Immunohistochemical analysis possible 97.4% patients. primarily NNT respectively.