Surgery for pre- and minimally invasive lung adenocarcinoma.

Abstract Objective Adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) are the pre-and minimally invasive forms of lung adenocarcinoma. We aimed to investigate safety results and survival outcomes following different types of surgical resection in a large sample of patients with AIS/MIA. Methods Medical records of patients with lung AIS/MIA who underwent surgery between 2012 and 2017 were retrospectively reviewed. Clinical characteristics, surgical types and complications, recurrence-free survival (RFS) and overall survival (OS) were investigated. Results A total of 1644 patients (422 AIS and 1222 MIA) were included. The overall surgical complication rate was significantly lower in patients receiving wedge resection (1.0%), and was comparable between patients undergoing segmentectomy (3.3%) or lobectomy (5.6%). Grade≥3 complications occurred in 0.1% of the patients in the wedge resection group, and in a comparable proportion of patients in the segmentectomy group (1.5%) and the lobectomy group (1.5%). There was no lymph node metastasis. The 5-year RFS rate was 100%. The 5-year OS rate in the entire cohort was 98.8%, and was comparable among the wedge resection group (98.8%), the segmentectomy group (98.2%) and the lobectomy group (99.4%). Conclusions Sublobar resection, especially wedge resection without lymph node dissection may be the preferred surgical procedure for patients with AIS/MIA. If there are no risk factors, postoperative follow-up intervals may be extended. These implications should be validated in further studies.