High-Risk Features Associated with Recurrence in Stage I Lung Adenocarcinoma

Objective There is a lack of knowledge regarding the use of prognostic features in stage I lung adenocarcinoma (LUAD). Thus, we investigated clinicopathologic features associated with recurrence after complete resection for stage I LUAD. Methods We performed a retrospective analysis of patients with pathologic stage I LUAD who underwent R0 resection from 2010 to 2020. Exclusion criteria included history of lung cancer, induction or adjuvant therapy, noninvasive or mucinous LUAD, and death within 90 days of surgery. Fine and Gray competing-risk regression assessed associations between clinicopathologic features and disease recurrence. Results In total, 1912 patients met inclusion criteria. Most patients (1565 [82%]) had stage IA LUAD, and 250 developed recurrence: 141 (56%) distant and 109 (44%) locoregional only. The 5-year cumulative incidence of recurrence was 12% (95% confidence interval, 11%-14%). Higher maximum standardized uptake value of the primary tumor (hazard ratio [HR]=1.04), sublobar resection (HR=2.04), higher IASLC grade (HR=5.32 [grade 2]; HR=7.93 [grade 3]), lymphovascular invasion (HR=1.70), visceral pleural invasion (HR=1.54), and tumor size (HR=1.30) were independently associated with hazard of recurrence. Tumors with 3-4 high-risk features had a higher cumulative incidence of recurrence at 5 years than tumors without these features (30% vs. 4%; p<0.001). Conclusions Recurrence after resection for stage I LUAD remains an issue for select patients. Commonly reported clinicopathologic features can be used to define patients at high risk of recurrence and should be considered when assessing the prognosis of patients with stage I disease.