Frequency of fibroblast growth factor receptor 1 gene amplification in oral tongue squamous cell carcinomas and associations with clinical features and patient outcome.

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.