Predictive value of a prognostic model based on pathologic features in lung invasive adenocarcinoma

Abstract

Objectives: Tumor spread through air spaces (STAS) was recently reported as a novel risk factor for the prognosis of patients with resected lung adenocarcinoma that indicates invasive tumor behavior. The purpose of this study was to build a prognostic model consisting of STAS and other pathologic features including visceral pleural invasion (VPI), vascular invasion (VI) and histological subtype (HS) in lung invasive adenocarcinoma.

Materials and methods: A total of 289 patients with resected lung invasive adenocarcinomas ≤4 cm were analyzed retrospectively to evaluate the potential prognostic value of STAS, VPI, VI and HS for recurrence-free survival (RFS) and overall survival (OS).

Results: STAS was observed in 143 patients (49.5%). Univariate and multivariate analysis showed that STAS, VPI, VI and HS were significant prognostic factors for poorer RFS and OS. Thus, a prognostic model including STAS, VPI, VI and HS was built using the results of the multivariate analysis. Nomograms were developed to predict the 5-year RFS and OS. The concordance index (C-index) of the prognostic model was 0.8122 for predicting 5-year RFS and 0.8539 for predicting 5-year OS in the internal validation. Moreover, the calibration curves for the 5-year RFS and OS showed that the nomograms were calibrated well. In addition, a similar predicted capability of the prognostic model was observed in the validation cohort.

Conclusion: STAS, VPI, VI and HS were significant prognostic factors for poorer RFS and OS. The prognostic model including STAS, VPI, VI and HS could effectively predict prognosis.

Keywords: Adenocarcinoma; Lung cancer; Prognostic model; Tumor spread through air spaces.