Response criteria for prostatic cancer treated by chemotherapy or antiandrogenic therapy

The efficacy of cytotoxic agents in the treatment of prostatic cancer is difficult to evaluate because objective, measurable lesions, such as lung, liver, skin, subcutaneous and nodal metastasis are often not found. However, most of the patients with advanced prostatic cancer have bone involvement and elevated serum acid-phosphatase in addition to the primary tumor. Exact clinical trials on such cases, especially phase II studies can not be performed without appropriate evaluations of these three parameters. The criteria of these three parameters offered by various study groups are reviewed and the relevant response criteria are proposed. A stable category was thought to be useful to evaluate the efficacy on the patients with progressing disease. In our proposal, overall assessment of response involves all objective parameters including these three parameters as well as both measurable and unmeasurable disease described in the WHO handbook for reporting results of cancer treatment.