Abstract
OBJECTIVES: Ground-glass opacity (GGO) component is a favourable prognostic factor in non-small cell lung cancer (NSCLC), whereas NSCLC with interstitial lung abnormalities (ILA) generally has poorer prognoses. We investigated the clinical significance of GGO in patients with NSCLC and ILA. METHODS: Among 1319 patients who underwent pulmonary resection for clinical stage IA NSCLC at 2 institutions between 2010 and 2020, we retrospectively assessed 216 patients with ILA based on preoperative CT. Patients were divided into 2 groups: pure solid tumours without GGO and subsolid tumours with GGO. RESULTS: Among 216 patients with ILA, 146 (68%) had pure solid tumours and 70 (32%) had subsolid tumours. Subsolid tumours had significantly better prognoses than pure solid tumours (5-year overall survival, 69.7% vs 48.6%, P = .0008; 5-year recurrence-free survival, 69.7% vs 42.3%, P < .0001). Recurrence occurred in 4 patients (6%) with subsolid tumours and 41 (28%) with pure solid tumours. Although the 5-year cumulative incidence of lung cancer deaths was significantly lower in subsolid tumours than in those with pure solid tumours (2.6% vs 23.6%, P = .0011), an increase in other causes of mortality after 2 years post-surgery in subsolid tumours resulted in a comparable 5-year cumulative incidence of other causes of death (28.4% vs 36.1%, P = .260). CONCLUSIONS: In clinical stage IA NSCLC with ILA, subsolid tumours have a lower lung cancer mortality than pure solid tumours; however, higher other-cause mortality after 2 years contributes to poorer overall survival. Optimizing comorbidity management may improve long-term prognosis.