A Proposal for the Repositioning of Prophylactic Breast Radiotherapy of Prostate Cancer Patients

Abstract

Patients with prostate cancer treated with small-molecular, nonsteroidal anti-androgens frequently develop mammalgia and gynecomastia. To avoid these unwanted effects, pretherapeutic radiation therapy of the male breasts is in common use. Recent findings on the effectivity of prevention and treatment of breast pain and gynecomastia, by both radiation therapy and tamoxifen, and a new comparative study, necessitate a re-evaluation of current prophylactic and therapeutic treatment options. An evidence-based treatment algorithm is derived that diverges from previous recommendations and redefines the role of preventive and therapeutic radiation therapy. For the propylaxis of gynecomastia and breast pain, tamoxifen is superior to single-dose radiation therapy with 10 Gy. Hence, if tamoxifen for this indication should prove to be safe on longer follow-up, radiation therapy would only be indicated in situations where tamoxifen therapy is impossible or contraindicated. The same is proposed for the treatment of early gynecomastia or breast pain except with tamoxifen treatment failure as an additional indication. Higher radiation doses of 4 x 5 Gy, which were shown to be effective in this setting, have not yet been evaluated against anti-estrogen therapy.