Sublobectomy versus lobectomy for peripheral small-sized pulmonary mucinous adenocarcinoma.

Background: Pulmonary mucinous adenocarcinoma (PMA), a rare type of adenocarcinoma, remains controversial in terms of its associated prognosis. We conducted this study to compare the oncological outcomes of lobectomy and sublobectomy for peripheral small-sized PMA.

Methods: This retrospective observational study included all patients with peripheral small-sized (≤2 cm) clinical stage IA1-A2 PMA who underwent lobectomy or sublobectomy (with margin distances ≥2 cm or greater than tumor diameter) between January 2015 and December 2018. Recurrence-free survival (RFS) and overall survival (OS) were compared between the lobectomy and sublobectomy groups with Kaplan-Meier curves and log-rank tests.

Results: This study examined 279 patients, with 176 cases in the lobectomy group and 103 cases in the sublobectomy group. Recurrence occurred in 8 patients, and 6 patients died. Before and after propensity score matching (PSM), log-rank tests showed no statistical differences between the lobectomy and sublobectomy groups in terms of 5-year RFS (before PSM: 97.0% vs. 98.9%; after PSM: 94.6% vs. 98.9%) or 5-year OS (before PSM: 96.9% vs. 98.8%; after PSM: 94.8% vs. 98.8%), and the recurrence patterns were also similar between the two groups. The incidence of postoperative complications, such as bronchopleural fistula, hydrothorax requiring redrainage, chylothorax, respiratory failure, and pulmonary embolism, also did not differ between the two groups.

Conclusions: For peripheral small-sized PMA, sublobectomy yielded an RFS and OS comparable to those of lobectomy.