O2-4-3 - Overall survival (OS) of EGFR mutation-positive non-small cell lung cancer (NSCLC): 1,660 Japanese patients (pts)

Abstract

Background: Since the 1st epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) was launched in Japan, the survival of EGFR mutation positive (EGFR m+) advanced/recurrent NSCLC pts have been getting longer. However, clinical factors contributing to the longer survival remains unclear. Methods: This is a multi-center, observational, retrospective study. NSCLC pts who started first-line treatment from 2008 to 2012 were enrolled. Eligible pts were diagnosed with EGFR m+ advanced/recurrent NSCLC by tissue or cytology samples. The primary objective was an OS. The secondary objectives were to determine prognostic factors and treatment patterns. In order to explore the effects of treatment sequence on OS, “Dynamic Treatment Regimen Analysis (DTRA)” was conducted. Results: 1,660 NSCLC pts were enrolled from 17 centers in Japan: 64.8% of female, median age of 67.0, 95.2% had adenocarcinoma, 50.1% had exon 19 del, 66.7% at stage IV, and Performance Status (PS) 0 or 1 were 80.1%. Median OS was 30.8 months (M). Cox regression analysis revealed sex, age, histology, EGFR mutation type, clinical stage and PS were independently associated with OS. 3.3% of pts never received EGFR-TKI, whilst 49.8% pts never received platinum (Pt) doublet chemotherapy in his/her whole treatment. The median number of treatment regimens was 2. Most frequently used 1st line treatment category was gefitinib (58.1%), followed by Pt doublet +/- bevacizumab (30.7%). Median OS for each was 29.07 M [95% CI, 26.87 to 31.60], and 35.13 M [95% CI, 30.70 to 38.30] respectively, although there is no difference by multivariate analysis. For DTRA, survival curves were estimated for treatment sequences by 2nd line and after. Conclusion: Real world treatments of the large data-set in EGFR m+ NSCLC pts were retrospectively investigated. First generation EGFR-TKIs were major components of the treatment regimens for this population either 1st or 2nd-line therapy in Japan. (NCT0247520)