Impact on survival of station 9 and necessity of inferior pulmonary ligament dissection in upper lobectomy for lung cancer

Abstract

Background: We conducted this study to investigate the need for dissection of station 9 lymph nodes during upper lobectomy for lung cancer and to find out the operative results of inferior pulmonary ligament division.

Methods: Patients with primary lung cancer who underwent surgery between January 2007 and June 2020 were retrospectively analyzed. Patients who underwent upper lobectomy and mediastinal node dissection were a basis for the study. The patients were separated into two groups – those having undergone lymph node dissection of station 9 and inferior pulmonary ligament dissection (Group I) and those who did not (Group II). In these groups, the prognostic value of station 9 lymph nodes and postoperative effects of ligament division were analyzed.

Results: A total number of 1000 patients were included in this research. The number of station 9 lymph nodes with metastases was only two (0.2%) and both were multi-station pN2 disease. While 5-year survival was 62.9% in 833 patients of Group I, it was 59% in 167 patients of Group II (p = 0.43). There was no statistically significant difference between the groups in terms of mean drainage time, length of postoperative hospital stay, prolonged air leak, and the free space filling rate of the residual lung in the upper thorax.

Conclusions: In upper lobectomies, status of station 9 does not have a significant effect on survival.Routine dissection of station 9 may not be necessary in upper lobectomies.Preservation or division of the inferior pulmonary ligament has no significant advantage or disadvantage.