Evaluation of the significance of subcarinal lymph node dissection in stage IB non‑small cell lung cancer.

Lymph node dissection is used to treat early-stage lung cancer. The present study aimed to investigate if resecting the subcarinal lymph nodes affects prognosis of patients with stage IB non-small cell lung cancer (NSCLC). A total of 597 patients with stage IB NSCLC who underwent lung cancer surgery at Sun Yat-Sen University Cancer Center from January 1999 to December 2009 were included in the present study. The potential prognostic factors were evaluated using the Cox proportional hazard regression model. A total of 252 cases were obtained following propensity score matching (PSM). To compare overall survival (OS) and recurrence-free survival (RFS), Kaplan-Meier method and log-rank test were used. Among the 597 cases included, 185 did not undergo subcarinal lymph node resection, whereas 412 did. There were statistically significant differences between the two groups in terms of bronchial invasion, number of resected lymph node stations and resected lymph node numbers (P<0.05). Age, family history of cancer and the number of resected lymph nodes were prognostic factors for OS, whereas age and the number of resected lymph nodes were prognostic factors for RFS (P<0.05). Resection of subcarinal lymph nodes was not associated with OS and RFS. After PSM, survival analysis was recalculated using the Kaplan-Meier method and log-rank test; subcarinal lymph node resection was not statistically associated with OS and RFS. (P>0.05). For stage IB NSCLC, there was no statistically significant association between subcarinal lymph node resection and OS and RFS. Subcarinal lymph node resection in surgery of stage IB NSCLC may be considered optional.