Improving the preservation of erectile function after external beam radiation therapy for prostate cancer

Background and purpose: To investigate whether the type of collimation technique, target dose and treated volume influence the prevalence of intact erectile function after external beam radiation therapy for localized prostate cancer. Patients and methods: A prospective study was conducted to assess erection stiffness before treatment and after follow-ups of 9-18 months and 4-5.5 years. Information was collected using the Radiumhemmet Scale of Sexual Function. Results: Thirty-one men were 'potent' before the radiation. Fourteen of them were treated with a conventional collimator and 17 were given three-dimensional conformal therapy with the aid of a multileaf collimator. Preserved erectile function at 9-18 months was found in 17 of the 31 men (55%) and at the 4-5-year follow-up in five of 22 (23%). Preservation of potency was related to the treatment procedure but not to the treatment volume. Conclusions: Conformal therapy may increase the percentage of men preserving erectile function during radiotherapy for localized prostate cancer; it is possible that the differences to conventional therapy do not depend on treated volume. Copyright (C) 2000 Elsevier Science Ireland Ltd.