Prognostic impact of lymphadenectomy on outcomes of sublobar resection for stage IA non-small cell lung cancer ≤2 cm.

Objective: To investigate the prognostic impact of lymph node (LN) dissection on sublobar resection for stage IA non-small cell lung cancer (NSCLC) tumors <= 2 cm. Methods: All patients who underwent sublobar resection for stage IA NSCLC tumors <= 2 cm were identified from the Surveillance, Epidemiology and End Results database. Patients were classified into no-LN dissection and LN dissection groups, and the latter was subclassified by the extent of LN dissection (1-3 regional LNs or >= 4 regional LNs). These groups were compared in terms of lung cancer-specific survival (LCSS) and overall survival (OS) rates. Propensity score-matched comparative analysis and a Cox regression model were used. Results: A total of 3269 patients met our criteria, including 1459 (44.6%) who underwent no LN dissection, 891 (27.3%) who underwent dissection of 1 to 3 regional LNs, 919 (28.1%) who underwent dissection of >= 4 regional LNs. Compared with no LN dissection, LN dissection was associated with more favorable LCSS and OS rates in patients who underwent sublobar resection for stage IA tumors <= 2 cm. More extensive regional LN dissection (>= 4 regional LNs) was associated with better LCSS and OS rates compared with less extensive regional LN dissection (1 to 3 regional LNs). A multivariable analysis of our patient population revealed independent associations of no LN dissection and less extensive regional LN dissection with poorer LCSS and OS rates compared with overall LN dissection and more extensive regional LN dissection, respectively. Conclusions: This propensity score-matched analysis reveals an association of LN dissection, particularly more extensive regional LN dissection (>= 4 regional LNs), with better survival rates in patients who undergo sublobar resection for stage IA NSCLC tumors <= 2 cm.