Early and late recurrence after intentional limited resection for cT1aN0M0, non-small cell lung cancer: from a multi-institutional, retrospective analysis in Japan

OBJECTIVES In 2015, we reported the outcomes of patients undergoing intentional limited resection (ILR) for non-small-cell lung cancer (NSCLC) from a retrospective, multi-institutional large database in Japan. Here, we analyse the clinicopathological characteristics of the patients extracted from this database with late recurrence and compare them with those with early recurrence. METHODS Of 1538 patients in the database with cT1aN0M0 NSCLC, 92 (6%) had recurrence. In this study, early recurrence was defined as recurrence within 5 years and late recurrence as recurrence beyond 5 years after surgery. We compared the clinicopathological characteristics and post-recurrence survival (PRS) between patients with early and late recurrence. RESULTS Of the 92 patients with recurrence, 21 (23%) had late recurrence. Compared with the early recurrence group, there were significantly more adenocarcinomas and local recurrences in the late recurrence group (P = 0.04 for both). The 3- and 5-year PRS rates were 53 and 24%, respectively, and the median PRS period was 38 months. There were no significant differences in the PRS curves between patients with early and late recurrence (P = 0.12). Only 3 patients (0.2%) had recurrence more than 10 years after ILR. Of the 21 late-recurrence patients, 17 (81%) had tumours with a consolidation/tumour ratio (CTR) >0.25. CONCLUSIONS Late recurrence occurred in 21 (23%) of 92 patients with recurrence after ILR for cT1aN0M0 NSCLC. Late recurrence was more likely to involve adenocarcinoma and local recurrence. It is thus considered reasonable to follow patients with a CTR >0.25 for 10 years after ILR.