Lymph node dissection as a local control during segmentectomy for small-sized and radiologically solid dominant and pure solid tumors.

[BACKGROUND] Small-sized, peripherally located, and radiologically solid-dominant or pure solid nonsmall cell lung cancer (NSCLC) tumors are related to lymph node metastasis at a certain frequency. The aim of this study is to disclose the validity of lymph node dissection on oncological local control during segmentectomy for such tumors.

[METHODS] We investigated the clinicopathological findings, the distribution of the involved lymph nodes, the patterns of lymph node recurrences, and the prognosis of 1921 patients with radiologically-determined ≤3 cm-sized, solid-dominant or pure solid NSCLC tumors without clinical lymph node involvement following complete resections with lobectomy (n = 1472) or segmentectomy (n = 449) between 2010 and 2020. The median follow-up duration for anonymized cases was 51.8 months.

[RESULTS] The median age, solid tumor size, whole tumor size, and maximum of standardized uptake value were 72/69 years, 1.5/1.8 cm, 1.6/2.1 cm, and 2.0/3.5 in patients undergoing segmentectomy/lobectomy, respectively. Hilar lymph node metastases were recognized in 13 (3%) patients who underwent segmentectomy, and in 110 (8%) patients who underwent lobectomy, respectively. No patients experienced a recurrence of hilar lymph node metastasis in either adjacent or nonadjacent areas without distant metastasis after segmentectomy, while three patients experienced recurrence after lobectomy.

[CONCLUSIONS] Lymph node dissection can be adequately performed during segmentectomy for selected small and peripherally located NSCLC tumors.