PROGNOSTIC-SIGNIFICANCE OF THE MICROVASCULAR COUNT IN COLORECTAL-CANCER

Purpose: To investigate the potential correlations between a high micr ovascular count and the survival rate in colorectal cancer. Materials and Methods: Three markers for endothelial cells-Ulex Europaeus Lectin (UEA), a polyclonal anti-van Willebrand factor (VWF) antibody, and a monoclonal anti-CD31 antibody(all from Dakopatts, Glostrup, Denmark)-w ere used for immunohistochemical detection of microvessels in whole-mo unt sections from 15 colorectal cancers. Areas with higher microvascul ar density were homogeneously distributed in the sections, regardless of the marker used. The and-vWF antibody was subsequently used for qua ntification of microvessels in full-cross tumor biopsies collected fro m 212 consecutive surgical specimens. The correlations between the mea n number of microvessels in areas with the highest microvascular densi ty and tumor differentiation, tumor stage according to Dukes', and sur vival time were investigated. Results: A significantly longer survival time was shown for patients who had tumors with a mean of more than 1 0 anti-vWf-positive microvessels, as compared with those who had less than or equal to five. Tumors with a microvascular count between six a nd 10 microvessels behaved in-between. There was no correlation betwee n the number of microvessels and tumor differentiation or Dukes' stage . Conclusion: The number of microvessels measurable in tumor biopsies seems to be a prognostic predictor independent of Dukes' stage in colo rectal cancer. However, our results are opposite to the findings in ot her tumor types investigated so far; we found that a high microvascula r count predicted a longer survival time, rather than a shorter one. D etermination of the microvascular count can be of importance in therap y selection even before, or immediately after, surgery, ie, before Duk es' stage is known. (C) 1996 by American Society of Clinical Oncology.