Effect of ground-glass opacity components on the recurrence of pathological stage IB non-small cell lung cancer harboring epidermal growth factor receptor mutations.

Purpose: This study aimed to examine the influence of ground-glass opacity (GGO) on the prognosis of epidermal growth factor receptor (EGFR)-mutated pathological (p)-stage IB non-small cell lung cancer (NSCLC).

Methods: Between 2009 and 2021, 115 patients underwent complete anatomical lung resection with mediastinal lymphadenectomy for p-stage IB non-squamous NSCLC harboring common EGFR mutations. The patients were classified into the part-solid and pure-solid arms based on the presence of GGO components.

Results: The median follow-up time was 70.2 months. Sixty-seven patients (58%) had pure-solid tumors and 112 (97%) were diagnosed with adenocarcinoma. No patients received adjuvant EGFR-tyrosine kinase inhibitors (TKIs). The 5-year disease-free survival (DFS) rates in the pure-solid arm were significantly lower than those in the part-solid arm (5-year DFS: 45.3% vs. 86.8%, p < 0.01). The 5-year cumulative incidence of recurrence was higher in the pure-solid arm than that in the part-solid arm (49.9% vs. 9.0%, p < 0.01). A multivariable analysis revealed that pure-solid tumors were an independent prognostic predictor of disease-free survival, whereas pathological factors were not.

Conclusions: In EGFR-mutated p-stage IB NSCLC, pure-solid tumors were significant predictors of DFS. The presence of GGO components should be considered in the decision criteria for adjuvant therapy with TKIs.