Abstract
Background: Factors associated with the prognosis of patients with small cell lung cancer (SCLC) is relatively unknown, than of those with non-small cell lung cancer. This study was undertaken to identify the prognostic factors of SCLC. Methods: The medical records of 333 patients diagnosed with SCLC at tertiary hospital from January 1, 2008, to December 31, 2012 were retrospectively reviewed. Patients were categorized by age (${\leq}65$ years vs. >65 years) and by extent of disease (limited disease [LD] vs extensive disease [ED]). Overall survival and progression free survival rates were determined. Factors associated with prognosis were calculated using Cox's proportional hazard regression model. Results: Most baseline characteristics were similar in the LD and ED groups. Eastern Cooperative Oncology Group (ECOG) performance status (PS), first chemotherapy regimen, and prophylactic cranial irradiation (PCI) differed significantly in patients with LD and ED. Mean ECOG PS was significantly lower (p<0.001), first-line chemotherapy with etoposide-cisplatin was more frequent than with etoposide-carboplatin (p<0.001), and PCI was performed more frequently (p=0.019) in LD-SCLC than in ED-SCLC. Prognosis in the LD group was better in younger (${\leq}65$ years) than in older (>65 years) patients, but prognosis in the ED group was unrelated to age. Conclusion: This study showed that overall survival (OS) was significantly improved in younger than in older patients with LD-SCLC. Univariate and multivariate analyses showed that age, PCI and the sum of cycles were significant predictors of OS in patients with LD-SCLC. However, prognosis in the ED group was unrelated to age.