Differences in patterns of relapse and survival after relapse between lobectomy and sublobar resection for stage IA...

In the Japan Clinical Oncology Group 0802 trial, lung cancer-specific mortality was comparable between lobectomy and segmentectomy despite a higher rate of locoregional relapse after segmentectomy. We evaluated relapse patterns and postrelapse survival following lobectomy or sublobar resection.

This single-institution retrospective study included patients who underwent surgery for primary non-small cell lung cancer (NSCLC) between 2003 and 2022 and subsequently developed relapse. Overall survival was defined as the period from surgery (OS1) or from the date of relapse diagnosis (OS2) to death from any cause.

Among 362 patients with clinical stage IA NSCLC who developed relapse, isolated locoregional relapse accounted for 110 of 297 relapsed patients (37.0%) after lobectomy and 36 of 65 relapsed patients (55.4%) after sublobar resection. Among 59 patients treated with local consolidative therapy for isolated locoregional relapse, the 4-year OS2 rate was 76.4% (95% CI, 64.9%-89.8%). After inverse probability of treatment weighting, the 7-year OS1 rates were 49.3% (95% CI, 42.2%-57.6%) after lobectomy and 64.9% (95% CI, 52.4%-80.3%) after sublobar resection, and the 4-year OS2 rates were 49.6% (95% CI, 42.4%-57.9%) and 62.7% (95% CI, 49.5%-79.3%), respectively.

In this exploratory cohort of patients who developed postoperative relapse, relapse patterns differed between surgical groups, with isolated locoregional relapse representing a larger proportion of relapse in the sublobar resection group. Long-term survival was observed in selected patients treated with modern postrelapse therapies, including local consolidative therapy. These findings should be interpreted cautiously as hypothesis-generating.