Local Extension at the Hilum Region Is Associated With Worse Long-Term Survival in Stage I Non-Small Cell Lung Cancers

Abstract

The prognostic significance of hilar structures invasion, which remains undefined for non-small cell lung cancer (NSCLC), may have potential application for cancer staging. Tumor extension along the bronchus and pulmonary vessels was examined for survival significance. In all, 213 pathologically proved central-type stage I NSCLC cases were enrolled. Four study groups were assigned based on the extent of resections: standard lobectomy (group L, n=32), bronchoplastic procedures (group B, n=94), standard lobectomy combined with pulmonary angioplasty (group A, n=48), and bronchial sleeve resection combined with pulmonary artery angioplasty (group BA, n=39). Univariate and multivariate analysis were performed by the Kaplan-Meier method and the Cox regression model. There were 2 postoperative deaths (pulmonary embolism and serious pulmonary infection). Complications were noted in 39 patients (18.3%). Among these patients, the overall 5-year survival rate was 60.2%±0.05%, with a median survival time of 75.0±7.5 months. The 5-year survival rates of subgroups were 79.5%, 59.7%, 59.0%, and 47.9%, respectively for groups L, B, A, and BA. Univariate analysis indicated tumor size, bronchial invasion, arterial involvement, and type of operation as closely associated with long-term survival. Multivariate analysis indicated that type of operation and tumor size were the most prominent prognostic factors of 5-year survival. Proximal tumor extension into bronchus, invasions into extrapericardial pulmonary vessels, and tumor size were the most important risk factors for 5-year survival with central-type stage I NSCLC. Tumor extension in the hilum was highly related to prognosis and might provide pertinent information to accurately define a tumor ("T") subclass.