Preoperative predictive factors and the prognostic impact of spread through air spaces in clinical stage IA lung adenocarcinoma.

[PURPOSE] Spread through air spaces (STAS) is a poor prognostic factor for lung adenocarcinoma, particularly in patients undergoing limited resection, and its accurate prediction can improve the patient outcomes. This study evaluated the impact of STAS on the surgical outcomes and predictive factors.

[METHODS] We analyzed 511 patients with clinical stage IA lung adenocarcinoma who underwent curative resection between 2007 and 2022. STAS was assessed histologically, and logistic regression was used to identify the predictors. The recurrence-free and overall survival rates were also evaluated.

[RESULTS] Among the patients, 27.8% had STAS with significantly poor 5-year recurrence-free survival (65.6% vs. 88.5% in STAS-positive vs.-negative cases, respectively), particularly in patients treated with sublobar resection. STAS was an independent, poor prognostic factor for the recurrence-free survival in the sublobar group but not in the lobectomy group. Elevated serum carcinoembryonic antigen (≥ 5.8 ng/mL), consolidation tumor ratio (≥ 0.9), and SUVmax (≥ 2.3) were independent predictors. STAS positivity increased with the number of risk factors as follows: 8.0% (none), 27.1% (one), 38.5% (two), and 60.4% (all three).

[CONCLUSIONS] The prediction of STAS using carcinoembryonic antigen levels, consolidation tumor ratio, and SUVmax can guide surgical decision-making and facilitate the provision of individualized treatment strategies for stage IA lung adenocarcinoma.