Salvage intensity-modulated radiation therapy for locally recurrent prostate cancer after cryotherapy

Background: To summarize our results of intensity-modulated radiation therapy (IMRT) for prostate adenocarcinoma after cryotherapy failure. Materials and Methods: Patients underwent IMRT with curative intent for biochemically recurrent prostate cancer after cryotherapy. Radiation was delivered to a minimum dose of 72 Gy (range, 72-81 Gy). Acute and late treatment-related gastrointestinal and genitourinary effects were scored according to Common Toxicity Criteria version 3.0. Prostate-specific antigen failure was defined by Radiation Therapy Oncology Group-American Society for Therapeutic Radiology and Oncology 2006 consensus definition. Results: Nine patients were treated from 2008 to 2010. The median follow-up was 31 months (range, 15-40 months). The mean preradiotherapy prostate-specific antigen was 4.3 ng/mL (range, 1.07-15.6 ng/mL). The median elapsed time between cryotherapy and IMRT was 20.5 months (range, 8.5-56.5 months). Biochemical control was achieved in 7 patients. Two patients developed distant metastases shortly after completion of radiotherapy. No patients experienced grade 3 or higher toxicities. Conclusions: Our results suggest that high-dose IMRT after cryotherapy failure is well tolerated, without severe morbidity. The results also showed that IMRT can render a significant number of patients biochemically free of disease after initial cryotherapy. High-dose IMRT should be considered as a treatment option for these potentially salvageable cases.