Background: EGFR and ALK gene mutations differ in frequency in various populations, are more common in young, non-smoking women, and are predictors for response to targeted therapy. The objective of this study was to analyze the clinical characteristics of patients with these mutations, and to compare them to other lung cancer patients.
Methods: We identified 154 lung adenocarcinoma cases diagnosed from 2009-2015, here we present interim data on 100 patients. Baseline demographics, smoking history, exposure to agent orange, pathologic diagnoses, AJCC stage, treatment, and survival data were collected.
Results: At diagnosis, median age was 67 (46-90) years; 96 were male. AJCC stage was 1a (n = 3), 1b (n = 1), 2a (n = 3), 2b (n = 6), 3a (n = 16), 3b (n = 10), 4 (n = 61). 92 were white, 6 African American, and 2 Native American. 95% were smokers; 25 had multiple malignancies and, 22 were exposed to Agent Orange. 84 tumors were tested for EGFR; 78% were negative, 7.5% were positive, and 15% had insufficient material. None of 54 tumors tested for ALK had rearrangement. 68 received chemotherapy. Average survival was 20.7 (range 0-90) months; 16 patients remain alive.
EGFR positive patients includes 4 males and 2 females. 5 were smokers. None was exposed to Agent Orange or had other malignancies. Average age was 66 years (54-79). 3 were AJCC stage IV, 2 stage IIIb and 1 stage IIa. EGFR inhibitor treatment was given to 4 patients, 1 received conventional chemotherapy, and 1 declined treatment. Average survival was 19.6 ( 6-35)months; 2 remain alive.
Conclusions: In our population only a low percentage of patients has EGFR mutation and even fewer have ALK rearrangement. However, a greater proportion of patients with EGFR positive tumors are women (33% vs 4%). Smoking history should not exclude patients from evaluation for targeted therapy. While no difference in survival was observed, this may be due to the small number of patients in the EGFR-inhibitor treated group. A larger study using The National VA Tumor Registry may provide more information to help guide testing and treatment of these patients. Updated data will be presented at the AVAHO Annual Meeting.
