Immunohistochemical microvessel count is not a reliable prognostic predictor in colorectal carcinoma

Immunohistochemical microvessel count for angiogenesis is associated with the growth and metastasis of various solid tumors, but its role in colorectal carcinoma remains controversial. This study aimed to determine its role in predicting the relapse and survival of colorectal carcinomas after curative surgery.

Representative paraffin-embedded sections of invasive colorectal cancers from 104 patients were studied by immunohistochemical staining using polyclonal anti-factor VIII antibody. Two investigators examined the microvessel count in the hot spot area of tumor using a 400x field in a blind fashion.

There was no correlation between microvessel count and tumor size, location of carcinoma, tumor cell differentiation and nodal status. The microvessel count appeared to be lower among advanced-stage cancers as compared with early-stage cancers (pN0 vs. pN1+ pN2: 56 +/- 25. vs. 50 +/- 20; Dukes A + B vs. C + D: 56 +/- 25 vs. 49 +/- 18). In node-negative patients, the value of microvessel count greater than or equal to 75 seemed to correlate with longer disease-free survival and overall survival.

Based on these results, immunohistochemical microvessel count seemed to decrease as colorectal cancer progressed and was not a reliable prognostic predictor in colorectal carcinoma.