Organization of Nationwide Egfr Testing in Russia: First Experience

Abstract

ABSTRACT Aim: EGFR mutations are associated with pronounced sensitivity of lung carcinomas (LC) to EGFR inhibitors, therefore EGFR testing is now considered to be a mandatory part of metastatic LC management. Frequency of EGFR mutations demonstrates significant racial and geographic variations. This study was supported by the Russian Society of Clinical Oncology and aimed to assess distribution of EGFR mutations in a large sample of Russian LC patients with inoperable LC. Methods: Diagnostic EGFR testing was carried out within years 2013-2014 in 9 laboratories spread across various regions of Russia. The laboratories were permitted to choose the methodology of EGFR mutation detection according to their preferences. Results: EGFR mutations were detected in 1043/4981 (20.9%) adenocarcinomas (AC), 13/396 (3.3%) squamous cell carcinomas and 2/75 (2.7%) large cell carcinomas. Frequency of EGFR mutations in AC exceeded similar estimates in other white populations, that may be attributed to higher proportion of non-smokers in Russian patients with AC. Noticeable occurrence of EGFR mutations in squamous LC may be explained either by regional specifics or inconsistencies in histological LC subtyping. EGFR mutation frequency was higher in patients aged 60 or older (605/2836, 21.3%) than in younger subjects (466/2744, 17.0%) (p=0.000037). Contrary to ALK-mutated LC, young onset LC with mutations showed the lowest estimates of EGFR mutation occurrence (21-30 years: 2/28 (7.1%); 31-40 years: 23/179 (12.8%). Conclusions: Russian patients with lung adenocarcinomas have high frequency of EGFR mutations. Distribution of EGFR mutations is age-related, being lowest in young-onset and highest in late-onset LC. Disclosure: All authors have declared no conflicts of interest.