Subserosal vascular density predicts oncological features of T2 gallbladder cancer

Abstract

Purpose: Tumor sidedness (hepatic side vs. peritoneal side) reportedly predicts microvascular invasion and survival outcomes of T2 gallbladder cancer, although the actual histopathological mechanism is not fully understood.

Methods: The clinical relevance of tumor sidedness was revisited in 84 patients with gallbladder cancer using histopathological analysis of the vascular density of the gallbladder wall.

Results: Hepatic-side tumor location was associated with overall survival (OS) (hazard ratio [HR], 13.62; 95% confidence interval [CI], 2.09-88.93) and recurrence-free survival (RFS) (HR, 8.70; 95% CI, 1.36-55.69) in T2 tumors. The Adjusted Kaplan-Meier curve indicated a clear survival difference between T2a (peritoneal side) and T2b (hepatic side) tumors (P = 0.006). A review of 56 pathological specimens with gallbladder cancer and 20 control specimens demonstrated that subserosal vascular density was significantly higher on the hepatic side of the gallbladder, regardless of the presence of cancer (P < 0.001). Multivariate analysis also confirmed that higher subserosal vascular density was significantly associated with poor OS (HR, 1.73; 95% CI, 1.10-2.73 per 10 microscopic fields) and poor RFS (HR, 1.62; 95% CI, 1.06-2.49) in T2 gallbladder cancer.

Conclusion: Higher subserosal vascular density may account for the higher incidence of cancer spread and the poor prognosis of T2b gallbladder cancer.

Keywords: Gallbladder cancer; Microvascular invasion; Surgery; Tumor location; Vascular density.