Tumour angiogenesis in prostatic carcinoma with and without bone marrow metastasis: a morphometric study

One hundred and one cases of clinical prostatic carcinoma (PCa), primary site, were analysed to define the interrelationship between tumour angiogenesis, histological grade, and bone marrow metastasis. Tumour angiogenesis was determined by the blood capillary density ratio (BCDR; a/b), defined as the ratio between the area of the blood capillaries (a) and the area of the tumour (b). The BCDR was evaluated by a colour image analysis system employing a computerized morphometrical method. A total of 43 cases of PCa with bone marrow metastasis (stage D2) and 58 cases of PCa without metastasis (stage B, C) were utilized. The prostatic carcinomas were classified into three groups (low, intermediate, and high) using Gleason's grading system. The BCDR of the primary PCa with bone marrow metastasis was similar in each of the three histologically graded scores. On the other hand, in the cases of PCa without metastasis, the BCDR of high score PCa was higher than those of the low and intermediate score PCa (U-test; P < 0.001). The BCDR of the high score PCa without metastasis was similar to that of the PCa with bone marrow metastasis. The BCDR may provide help in predicting tumour progression with regard to bone marrow metastasis of PCa with low and intermediate Gleason's scores.