FOLLOW-UP EVALUATION OF NATIONAL PROSTATIC-CANCER PROJECT PROTOCOLS AND OTHER STUDIES

Objective. This report describes follow-up data on various protocols from the National Prostate Cancer Project (NPCP) and other Phase I and Phase II studies dealing with possible new active agents. Methods. Analysis of completed, ongoing, and projected trials for metastatic prostate cancer and hormone-refractory disease. Results. Long-term results are now approaching 12 years for two protocols for stages B2-D1 prostate cancer. A significant survival difference in the D1 radiotherapy group is reported for those treated with estramustine phosphate. The number of nodes involved is an important prognostic factor. Other data suggest that methotrexate has an effect in combination with hormonal therapy for newly diagnosed metastatic disease. Methods for dealing with relapsing disease and the utilization of prostate-specific antigen allow greater precision in the evaluation of Phase II studies. Alternative agents such as diethylstilbestrol are inexpensive and can be given under intravenous therapy on an outpatient basis in high dosage with significant results and minimal toxicity. Conclusions. The NPCP protocols, particularly studies of adjuvant therapy for localized disease, continue to suggest that adjuvant treatment has a survival benefit. Other new agents have yet to be tried in newly diagnosed metastatic disease. The results of NPCP studies may be further benefited by additional prospective randomized trials.