Surgery in patients with small cell lung cancer: A period propensity score matching analysis of the Seer database, 2010-2015

Surgery as a therapeutic modality for non-small cell lung cancer is widely accepted in clinical practice. However, the role of surgery for small cell lung cancer (SCLC) remains controversial. Therefore, in the present study a period propensity score matching analysis using the Surveillance, Epidemiology and End Results (SEER) Registry database was performed to investigate the role of surgery on survival in patients with SCLC. Patients with SCLC between January 2010 and December 2015 were identified from the SEER database, and individual data for each case regarding general clinical characteristics, surgery of primary site (SPS), cause-specific death classification and survival time were retrieved. Differences of cause-specific survival (CSS) between subgroups were estimated by the log-rank test. Cox regression analysis was used to evaluate the effects of multiple variables on CSS, and differences between the incidences of cause-specific death were examined using a χ(2) test. A total of 1,707 records met the inclusion criteria and were retrieved for analysis. There were significant differences of CSS in the clinicopathological features of N (P=0.01), Stage (P<0.01) and Surgery (P<0.01) when comparing non-surgery with surgery, and in N (P<0.001), Stage (P=0.006) and Surgery (P=0.049) when comparing sublobectomy with lobectomy or bilobectomy (lobe/s). Patients who did not receive surgery (P<0.001) or who received sublobectomy (P=0.03) had an increased risk of mortality when compared with patients who received surgery and lobe/s. The findings of the present study indicate that surgery should be taken into consideration when an initial treatment strategy is made in patients for patients with SCLC at clinical stage I–IIA (T1-2,N0,M0), regardless of whether they are >50 years of age, their sex, histology and grade. The results suggest that certain patients with SCLC with stage IIB (N1) can also benefit from lobe/s, although further investigation is required. In addition, lobe/s is preferable to sublobectomy when surgery is performed. However, the present study was unable to comprehensively analyze the efficacy of pneumonectomy for SCLC.