Excellent survival of pathological N0 small cell lung cancer patients following surgery.

Background: Current clinical guidelines recommend surgery only for cT1-2N0M0 small cell lung cancer (SCLC) patients. In light of recent studies, the role of surgery in the treatment of SCLC needs to be reconsidered.

Methods: We reviewed all SCLC patients who underwent surgery from November 2006 to April 2021. Clinicopathological characteristics were retrospectively collected from medical records. Survival analysis was performed by the Kaplan-Meier method. Independent prognostic factors were evaluated by Cox proportional hazard model.

Results: 196 SCLC patients undergoing surgical resection were enrolled. The 5-year overall survival for the entire cohort was 49.0% (95% CI: 40.1-58.5%). PN0 patients had significantly superior survival to pN1-2 patients (p < 0.001). The 5-year survival rate of pN0 and pN1-2 patients were 65.5% (95% CI: 54.0-80.8%) and 35.1% (95% CI: 23.3-46.6%), respectively. Multivariate analysis revealed that smoking, older age, and advanced pathological T and N stages were independently associated with poor prognosis. Subgroup analyses demonstrated similar survival among pN0 SCLC patients regardless of pathological T stages (p = 0.416). Furthermore, multivariate analysis showed factors, including age, smoking history, type of surgery, and range of resection, were not independently prognostic factors for the pN0 SCLC patients.

Conclusion: Pathological N0 stage SCLC patients have significantly superior survival to pN1-2 patients, regardless of features, including T stage. Thorough preoperative evaluation should be applied to estimate the status of lymph node involvement to achieve better selection of patients who might be candidate for surgery. Studies with larger cohort might help verify the benefit of surgery, especially for T3/4 patients.