The frequency and impact of FGFR1 amplification on clinical outcomes in Korean patients with small cell lung cancer

FGFR1 amplification was detected in three patients (1.9%) harboring extensive disease (ED). A multivariate analysis showed that among the patients with ED, FGFR1 amplification was associated with shorter disease-free survival to first-line chemotherapy with etoposide plus cisplatin or carboplatin (hazard ratio [HR] = 7.1; 95% confidence interval [CI] = 2.0-25.4; P = 0.003). The median overall survival time of the patients with ED was 8.2 and 10.2 months among patients with and without FGFR1 amplification, respectively (P = 0.37). Although FGFR1 amplification is rare in SCLC compared to non-small cell lung cancer or other malignancies with squamous histology, it is associated with poor survival following standard chemotherapy in SCLC. Further studies in large cohorts of patients with SCLC are needed to verify these results. Our results imply that FGFR1 may be a potential therapeutic target in SCLC and it could be confirmed in a clinical trial.