Role of Surgery in Potentially Resectable Small-Cell Lung Cancer Based on the Eighth Edition of the TNM Classification: A Population Study of the US SEER Database.

Background: This study aimed to identify a specific SCLC population that would benefit from surgery.

Methods: This study utilized patient data retrieved from the Surveillance, Epidemiology, and End Results (SEER) database spanning 2010 to 2017. To mitigate clinical biases, the propensity score matching (PSM) technique was employed. Separate cohorts were aligned using PSM according to the AJCC 8th edition TNM classification. The Kaplan-Meier method and a competing risk model were applied to evaluate overall survival (OS) and lung cancer-specific survival (LCSS), respectively.

Outcomes: Among the 3394 patients with potentially resectable SCLC included in the study, 3062 underwent chemoradiotherapy and 332 underwent surgical treatment with adjuvant chemotherapy. Surgery was associated with better OS (median OS: 49 months; 95% CI: 35-63 months vs. 27 months; 95% CI: 21-33 months, p < 0.001) and LCSS (SHR, 0.578; 95% CI: 0.411-0.815, p < 0.001) in stage I patients after PSM. However, there was no significant difference in OS and LCSS between the surgery and nonsurgery groups in stage II and III patients after PSM. In the entire cohort, lobectomy was associated with improved OS (median OS: 48.6 vs. 28.7 months, p < 0.0001), but not LCSS (SHR, 0.696; 95% CI: 0.466-1.040, p = 0.078) compared with sublobar resection after PSM.

Conclusion: Surgery with adjuvant chemotherapy significantly improved the survival prognosis of patients with early-stage SCLC. However, surgical treatment should be carefully considered in patients with stage II/III disease. Lobectomy is oncologically equal to sublobar resection.