TUMOR ANGIOGENESIS IN LATENT PROSTATIC-CARCINOMA

Unrestrained growth of various malignant tumours has been shown to dep end upon a critical number of tumour cells which have switched to the angiogenic phenotype. Angiogenic phenotypes were noted in the early st age of prostatic carcinoma (PCa). We investigated 65 cases of latent P Ca to define the correlation between tumour angiogenesis and tumour vo lume. Tumour angiogenesis was determined by the blood capillary densit y ratio (BCDR) evaluated by a colour image analysis system. Using expe rimental regression analysis, the correlation between the BCDR and PCa volume was divisible into two distinct stages. When the PCa showed a volume of more than 83 mm(3), there was a significant positive correla tion between the BCDR and PCa volume (rS-test P < 0.001). However, whe n the PCa showed a volume of less than 83 mm(3), the BCDR remained at a low level which did not change until larger volumes were present (rS -test, NS; ANOVA, NS). The present study suggested that latent PCa sho wing a volume of less than 83 mm(3) would be 'early' indolent carcinom a which, on undergoing additional events concerning tumour angiogenesi s, would assume more aggressive growth.