P3.02a-003 ALK and ROS1 Rearrangements, Coexistence and Treatment in EGFR-Wild Type Lung Adenocarcinoma - A Multicenter Study of 732 Cases: Topic: ALK

Abstract

Anaplastic lymphoma kinase (ALK) and c-ros oncogene 1 (ROS1) rearrangements represent two of the most frequency fusion targets in lung adenocarcinoma. The aim of this study was to investigate the clinicopathological characteristics, coexistence and treatment of ALK and ROS1- rearrangement patients in lung adenocarcinoma without EGFR mutations. Patients who harbored EGFR wild-type gene were screened for ALK and ROS1 gene in four Hospitals in China. ALK and ROS1 rearrangements were detected using RT-PCR. Progression free survival curves were plotted using the Kaplane-Meier method. Seven hundred and thirty-two patients enrolled in current study. Of the 732 patients, the median age was 59 years (range: 28–81). ALK and ROS1 rearrangements were detected in 89 (12.2%) and 32 (4.4%) patients, respectively. One patient was identified with ALK/ROS1 coexistence. Both of ALK and ROS1 positive were predominantly found in younger and non-smokers. More patients with ALK/ROS1 rearrangements were associated with TTF1 expression，napsin A expression and solid predominant adenocarcinoma subtype (Figure 1 ). ALK and ROS1 rearrangements frequency was enriched in EGFR wild-type patients and ALK/ROS1 coexistence was rare. The ALK and ROS1 arrangements were associated with age, smoking status, TTF1 expression, napsin A expression and solid predominant adnocarcinoma subtype.