Angiogenesis as an unfavorable prognostic factor in human colorectal carcinoma.

Angiogenesis is reportedly correlated with metastasis, relapse, and prognosis in some types of tumors. Hematogenous or lymph node metastasis and local recurrence are the main elements related to the death of patients with colorectal carcinoma. Thus, the authors examined the microvessel count in colorectal carcinoma to determine how angiogenesis correlates with clinicopathologic factors and prognosis. Paraffin embedded sections from 166 patients with primary colorectal carcinomas that had been completely removed were analyzed for angiogenesis. Vessels were stained with anti-factor VIII polyclonal antibody, and areas with the most discrete microvessels were counted in a 400x field. Tumor size was significantly correlated with microvessel count. Microvessel counts from patients with lymph node metastasis, lymphatic vessel invasion, venous vessel invasion, or relapse were significantly higher than those without. Furthermore, microvessel count was an independent prognostic factor (P = 0.007), whereas the Dukes stage had more significant prognostic value (P < 0.001) according to the multivariate Cox hazard analysis. This study suggested that angiogenesis assessed by the microvessel count was a marker of relapse and prognosis of patients with colorectal carcinoma.