Abstract 4728: FGFR1 gene amplification in small cell lung cancer

Abstract

Abstract Background: Fibroblast growth factor receptor 1 (FGFR1) received special attention from many clinicians according to finding that FGFR1 played a critical role in many human cancers. Some clinical trials using FGFR1 targeting agents are in progress especially in breast cancer and squamous non-small cell lung cancer. Recently, FGFR1 amplifications were also found in about 5.6-6% of small cell lung cancer (SCLC) by gene copy number analysis and FISH. Methods: Tumor tissues from 113 patients diagnosed with SCLC from October 2009 to February 2013 in YUHS, Korea were collected. FGFR1 FISH assay was performed on the tissue microarray using FISH probe that hybridized to the band 8p12-8p11.23 (FISH probes were provided by Abbott Molecular, Abbott Park, IL). Results: Thirty-two patients with limited-stage disease (LD) and eighty-one patients with extensive-stage disease (ED) were enrolled. Fourteen patients were female. Among 113 tumor samples, 5 samples (4.4%) showed FGFR1 amplification. All 5 samples were obtained from the patients with ED. The patients with FGFR1 amplification more frequently had pleural metastasis at the time of diagnosis (80% vs. 26%, P=0.022). In ED, the patients with FGFR1 amplification represented shorter disease free survival from first line chemotherapy (Hazard ratio [HR], 4.469; 95% confidence interval [CI], 1.600-12.483; P=0.004) and second line chemotherapy (HR, 6.533; 95% CI, 1.700-25.108; P=0.006) than the patients without FGFR1 amplification in multivariate analysis. Median overall survival time was 8.2 months in the patients with FGFR1 amplification and 10.2 months in the patients without FGFR1 amplifications (P=0.296). Conclusion: FGFR1 amplification is a poor potential predictive biomarker of standard chemotherapy, necessitating further research in a large cohort of SCLC. The validity of targeting FGFR1 in SCLC should be confirmed in a clinical trial. Citation Format: Ji Soo Park, Jae-Seok Lee, Hyo Sup Shim, Hye Ryun Kim, Sun Min Lim, Joo Hang Kim, Byoung Chul Cho. FGFR1 gene amplification in small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4728. doi:10.1158/1538-7445.AM2014-4728