It Is Worth Operating Small Cell Lung Cancer?

Objectives: Small cell lung cancer (SCLC) is a deadly disease due to its rapid growth and early dissemination to distant organs. Patients in the very limited disease can be treated with curative intend. The core aspect in this treatment is a combined platinum-based chemotherapy followed by radiotherapy. Despite some recent studies that show a survival benefit after surgery, its role in the treatment of SCLC remains controversial. In this meta-analysis we evaluate the 5-year survival of SCLC patients that were treated either with a surgical or a non-surgical approach.

Methods: We performed a systematic literature research on 15th June 2018 in Medline and Cochrane databases and included all articles that were published since 1952. Two groups were formed for a statistical comparison (group A: any surgical treatment; group B: non-surgical treatment, but radio-/chemotherapy). Only patients in very limited disease were included. Established statistical methods such as I ²-test and Q-statistics; Mantel–Haenszel’s test or DerSimonian–Laird’s test and Egger regression were performed.

Results: Out of 14,824 studies, we included 13 articles and a total of 91,802 patients (group A: n = 4,082; group B: n = 87,720) into this meta-analysis. Egger’s weighted regression statistic showed no significant publication bias (p-value = 0.4737). The baseline characteristics age and gender are not significant different and tumor stages were equally represented in both groups (p-value>0.05). The I ²-test suggested 97.7% inconsistency (95% CI: 97.1–98.1), providing evidence for significant heterogeneity between the included studies. We therefore implemented the DerSimonian and Laird random-effects model. The pooled odds ratio was 4.2 (95% CI: 2.2–8.2) and the chi-square test was 18.4 (p-value < 0.0001) in favor of the surgical approach. Surgical resection improved 5-year survival significantly (group A: 32.7 ± 9.4%; group B: 11.8 ± 6.1%; p-value < 0.0001). The post hoc power analysis suggested good power for the endpoint (effect size d: 1.78; power (1-β): 1.0; alpha error: 0.05) due to the large sample size.

Conclusion: Surgery has an important influence on the survival of SCLC patients. Guidelines recommend either surgery or nonsurgical treatment in early stages. This study suggests that all SCLC patients in early stages should be resected whenever possible due to the clear 5-year survival benefit.