However, short-term ADT is not without quality-of-life consequences, including hot flashes and higher rates of erectile dysfunction than with radiotherapy alone. Furthermore, erectile dysfunction may be less responsive to interventions after combined therapy than after radiotherapy alone. In prospective studies, short-term ADT caused measurable muscle loss, fat accumulation, decreased insulin sensitivity, and increased cholesterol and triglyceride levels. In the current study, the 10-year disease-specific mortality in the radiotherapy-alone group was 1%, a finding that does not provide support for the addition of short-term ADT in patients with low-risk prostate cancer. A total of 395 black men participated in this study, allowing evaluation according to racial subgroups. Similar benefits from short-term ADT were seen in the white and black populations with respect to the 10-year rate of overall survival, 10-year disease-specific mortality, and biochemical failure. Overall survival among black men was worse than that among white men, but disease-specific mortality was similar.

The results of our trial show that the addition of short-term ADT provides a survival benefit for men with intermediate-risk prostate cancer who receive conventional doses of radiotherapy. In addition, our findings suggest a biologic interaction between short-term ADT and radiotherapy, in contrast to several randomized trials of surgery combined with short-term ADT, which did not show a benefit with respect to outcome. The adoption of current radiotherapy techniques such as intensity-modulated radiation therapy, intensity-guided radiation therapy, and lowdose-rate and high-dose-rate brachytherapy now permits the safe delivery of higher doses of radiation than was possible when this study was conducted. These techniques have also been associated with improved efficacy,36-39 bringing into question the value of adding short-term ADT in men with intermediate-risk cancers treated with current irradiation methods. The RTOG has opened a successor study, RTOG 08-15 (NCT00936390), to address this question.

The contents of this article are solely the responsibility of the authors and do not necessarily represent the official views of the National Cancer Institute. Supported by grants (U10 CA21661, to the Radiation Therapy Oncology Group [RTOG]; U10 CA37422, to the Community Clinical Oncology Program; and U10 CA32115, to the RTOG Statistical Center) from the National Cancer Institute. Dr. Chetner reports receiving lecture fees from and serving on the advisory boards of Amgen, Ferring, GlaxoSmithKline, and Eli Lilly and receiving fees for the development of educational presentations from Amgen and GlaxoSmithKline; and Dr. Sandler, consulting fees from Calypso Medical and Varian. No other potential conflict of interest relevant to this article was reported.