Proposal on incorporating consolidation-to-tumor ratio into the clinical T1 classification in patients with invasive lung adenocarcinoma

Background: The prognostic implication of consolidation-to-tumor ratio (CTR) in patients with part-solid nodules (PSNs) remains ambiguous. The aim of this study is to explore the potential of CTR for refining prognostic stratification within the current clinical T1 classification. Methods: There were 1,340 N0M0 lung adenocarcinoma (LUAD) patients with PSNs (solid size ≤3 cm) enrolled. We constructed a novel risk stratification model based on both solid component size and CTR. The lung cancer-specific survival (LCSS) and recurrence-free survival (RFS) rates of the patients in the current and modified staging groups were evaluated. Results: . CTR >0.8, P=0.04). The CTR-incorporated stratification scheme clearly classified the prognosis of PSNs (LCSS: T1mi: 100%, T1a: 99.1%, T1b: 89.4%, T1c: 75.3%; RFS: T1mi: 100%, T1a: 98.2%, T1b: 87.6%, T1c: 66.9%). Conclusions: CTR had a significant effect on the prognosis of PSNs, even when the solid component sizes were similar. An exploratory staging model incorporating CTR showed potential for improving risk stratification over the current T1 classification, but warrants external validation in future studies.