Frequency of Fibroblast Growth Factor Receptor 1 gene amplification in oral tongue squamous cell carcinomas and associations with clinical features and patient outcome

Summary Objectives Novel therapies are required for patients with recurrent or metastatic oral tongue squamous cell carcinoma (OTSCC). Fibroblast Growth Factor Receptor 1 ( FGFR1 ) amplification frequently occurs in squamous cell carcinoma of the lung and represents a novel druggable therapeutic target in this and other malignancies. This study examined the frequency and clinical associations of FGFR1 amplification in OTSCC. Materials and methods The frequency of FGFR1 amplification determined by fluorescence in situ hybridization was evaluated in a cohort of 123 OTSCC patients. Associations of FGFR1 amplification with clinical characteristics and outcome were determined. Results FGFR1 gene amplification was present in 9.3% (10/107) of cases and was significantly associated with smoking status ( P = 0.03). FGFR1 amplification was seen more commonly in males (9/10 amplified cases male, P = 0.16) and there were no associations with age, stage, T stage, nodal status, alcohol history or performance status (all P > 0.05). Outcome was not significantly different between FGFR1 amplified and non-amplified patients. Conclusions Copy number variations of the FGFR1 gene occur in a subset of OTSCC with approximately 10% of cases showing amplification of the gene. FGFR1 amplification may represent a therapeutic target in OTSCC.