2000 Volume 53 Issue 6 Pages 396-399
Pathological examination was performed on prostatic tumors in 2 dogs (case 1: male golden retriever, 9 years old; case 2: male mongrel, 11 years old). The tumor in case 1 consisted of proliferated round to ellipsoid cells resembling prostatic epithelium arranged in sheets with many mitoses. The tumor in case 2 consisted of atypical epithelial cells demonstrating intra-acinar proliferation. In immunohistochemical examination using the antibody against human prostate specific antigen tumor cells in case 1 were negative, whereas those in case 2 were positive. Electron microscopy of case 1 showed large, atypical nuclei of tumor cells. Numbers of cellular organelles varied among tumor cells. No acini were present. In case 2, tumor cells formed small acini with slightly atypical nuclei, free ribosomes, and secretory granules. Desmosomes were noted in both cases. On the basis of these findings, case 1 was diagnosed as syncytial prostatic carcinoma and case 2 as intra-alveolar proliferative prostatic carcinoma.
