Histological effects of endocrine therapy for prostatic cancer in relation to clinical course.

In order to evaluate histological changes in cases of prostatic cancer following endocrine therapy, 25 extensive specimens were removed from prostates during periods of local control, and were examined with respect to prognosis. Shortly after the commencement of the endocrine therapy, there were noticeable degenerative changes in the cancer cells as well as structural changes such as desquamation of cells and loss of cancer nests. Later than two months from the start of therapy, stromal changes such as fibrosis and scar formation appeared. Coagulation necrosis of tumor tissue, inflammatory cell infiltration and granulomatous reactions were not as prominent. Within the first two months of treatment, the endocrine therapy uniformly affected the cancer tissues to some extent. After then, some showed relapsing viable cells in a part of the tumor, being judged to be no response. The others continued to respond to the therapy. The response was estimated as marked when such therapeutic changes appeared diffusely and profoundly over the tissues removed. Patients with a marked response had a good prognosis, indicating histological evaluation after endocrine therapy to provide a prognostic factor.