Resection outcomes according to pathologic risk in ≤2 cm invasive lung adenocarcinoma

To examine whether the oncologic adequacy of resection type differs according to biologic risk in small invasive lung adenocarcinoma.

We performed a multihospital retrospective study of patients who underwent resection for pathologic node-negative lung adenocarcinoma with invasive size ≤2 cm from 2010 to 2022. Tumors were classified as low-risk, high-risk, or very high-risk according to the presence of 0, ≥1, or ≥2 adverse pathologic features including spread through air spaces, lymphovascular invasion, visceral pleural invasion, and high-grade histology. Locoregional recurrence (LR) was evaluated using competing-risk cumulative incidence functions and multivariable Fine-Gray models. Overall survival and recurrence-free survival (RFS) were assessed using overlap-weighted Cox models.

Among 1436 patients (494 lobectomy, 316 segmentectomy, 626 wedge; median follow-up 45.5 months), 5-year LR remained low across resection types in the low-risk cohort but increased stepwise in the high-risk cohort from lobectomy to segmentectomy to wedge resection. In Fine-Gray models, wedge resection was associated with greater LR than lobectomy in the overall (subdistribution hazard ratio, 3.39; 95% CI, 1.86-6.20) and the high-risk (subdistribution hazard ratio, 2.71; 95% CI, 1.35-5.47) cohort. Hilar N1 station sampling was independently associated with lower LR in the high-risk cohort. In overlap-weighted analyses, overall survival and RFS favored lobectomy overall. In high-risk tumors, wedge resection was associated with worse RFS (hazard ratio, 1.62; 95% CI, 1.03-2.56).

The oncologic adequacy of resection extent varies according to tumor biology in node-negative invasive ≤2 cm lung adenocarcinomas. Low-risk tumors demonstrated low absolute LR across resection types, whereas high-risk tumors showed progressively less-favorable outcomes with lesser resection extent.