Blood Vessel Invasion Predicts Postoperative Survival Outcomes and Systemic Recurrence Regardless of Location or Blood Vessel Type in Patients with Lung Adenocarcinoma.

Background: Presence of blood vessel invasion (BVI) is one of the prognostic indicators for lung cancer patients with surgical resection. However, prognostic roles of the location and the type of the involved blood vessel have not been fully evaluated yet.

Patients And Methods: We retrieved the data of 217 cases of surgically resected lung adenocarcinoma from Asan Medical Center. Clinicopathologic features, including BVI, were reassessed. The location (tumor center and/or periphery) and involved blood vessel types (large and/or small vessels; arteries and/or veins) of BVI were separately examined on standard hematoxylin-eosin slides and confirmed by van Gieson elastic staining.

Results: BVI was identified in 35% of cases (76/217), with the tumor center (intratumoral) as the location in more than half of the cases (42/76, 55.3%). The presence of BVI was significantly associated with higher pathologic stage, increased size of invasive components, frequent pleural invasion, lymphatic permeation, and spread through alveolar spaces. BVI was significantly associated with poor overall survival (OS) and recurrence-free survival (RFS) both in univariate and multivariate survival analyses [for OS, hazard ratio (HR) 1.92, 95% confidence interval (CI) 1.06-3.48, P = 0.031; for RFS, HR 2.65, 95% CI 1.64-4.28; P < 0.001]. BVI subgroups, according to location and type of the involved blood vessels, invariably displayed significantly poor RFS; however, the results for OS varied.

Conclusion: Regardless of their location or blood vessel type, presence of BVI is a useful predictor for postoperative survival outcomes, which should be carefully evaluated on pathologic examination.