Radiation therapy after radical prostatectomy: strike early, strike hard! The case for adjuvant radiation therapy.

With a large local tumor, when surgical extirpation results in a positive surgical margin, adjuvant radiotherapy is the routine approach for a variety of solid tumors, such as head and neck cancers, rectal cancer, lung cancer, and breast cancer. With prostate cancer, however, surgery and radiotherapy are considered as alternative single-modality treatments, and their combination is far less enthusiastically embraced. Despite a trend toward earlier clinical diagnosis of prostate cancer since the introduction of prostate-specific antigen (PSA) screening, modern surgical series continue to show a 15%-25% incidence of positive surgical margins. Postoperative radiotherapy, whether delivered as "adjuvant therapy" shortly after surgery or as "salvage therapy" when serum PSA becomes detectable, effectively improves local control and prolongs disease-free survival.