ANGIOGENESIS IN MALIGNANT FIBROUS HISTIOCYTOMA

The significance of neovascularization for tumor growth and metastasis has recently been postulated for human cancers; increased microvessel density correlates with increased frequency of metastasis. In the pre sent study, microvessel density was examined in 42 cases of malignant fibrous histiocytoma (MFH). Microvessels were defined as lumens surrou nded by anti-factor-VIII-related antigen (FVIII-RA)-antibody-stained e ndothelium, and counted in a x 400 field. The number of microvessels v aried from 4 to 79 (median 14.5). When cases were divided into groups with less than or greater than 20 microvessels, there were no prominen t differences in age distribution, sex ratio, size of tumor, depth of tumor, and histologic subtypes between the two groups. The number of m icrovessels in 19 cases with and 22 cases without metastasis was 19.4 +/- 14.9 and 19.6 +/- 17.4, respectively. Angiogenesis is apparently n ot a key factor in the formation of metastasis by MFH.