Treatment outcome and toxicity after salvage 125-I implantation for prostate cancer recurrences after primary 125-I implantation and external beam radiotherapy

Purpose: To evaluate the outcome and toxicity after salvage iodine-125 (125-I) implantation in patients with locally recurrent prostate cancer after primary 125-I implantation and external beam radiotherapy.

Methods and materials: Retrospectively, 31 patients were analyzed with pathology-proven local recurrent prostate cancer after primary external beam radiotherapy (n=20) or 125-I implantation (n=11), and who had undergone salvage 125-I implantation between 1994 and 2009. For recording biochemical failure rates, the Phoenix definition and the American Society for Therapeutic Radiology and Oncology definition were applied. Toxicity was scored according to the Common Terminology Criteria for Adverse Events version 3.0 (CTCAE v3.0) (Cancer Therapy Evaluation Program, National Cancer Institute, National Institutes of Health, Bethesda, MD).

Results: The mean (+/-standard deviation [SD]) followup was 9 years (+/-4). The freedom from biochemical failure after 1 and 5 years' followup were 51% and 20%, respectively. Fourteen (45%) patients died of prostate cancer after a mean (+/-SD) followup of 73 (+/-39) months. Grade 1, 2, or 3 toxicity of the genitourinary tract was reported in 29%, 58% and 3% of the patients, respectively, in the acute phase, and in 16%, 39%, and 19%, respectively, in the late phase. Grade 1, 2, or 3 toxicity of the gastrointestinal tract was reported in 45%, 10%, and 0% of the patients, respectively, in the acute phase, and in 48%, 3%, and 6%, respectively, in the late phase. Grade 4 toxicity of any tract occurred in none of the patients in the acute or the late phase.

Conclusions: Freedom from biochemical failure after salvage 125-I implantation for locally recurrent prostate cancer after radiotherapy is limited, and both genitourinary and gastrointestinal toxicity occur frequently.