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Updated: Jul 30, 2026
A Bioluminescent and Fluorescent Orthotopic Syngeneic Murine Model of Androgen-dependent and Castration-resistant Prostate Cancer
Published on: March 6, 2018
[Favorable effect of sildenafil on erectile dysfunction in patients after radiotherapy for prostate cancer;
L Incrocci1, W C J Hop, A K Slob
1Erasmus Medisch Centrum, Daniel den Hoed Kliniek, Rotterdam, Netherlands. l.incrocci@erasmusmc.nl
Objective:
To determine the efficacy of sildenafil in patients with erectile dysfunction after external beam radiotherapy for prostate cancer.
Design:
Randomised, double-blind, placebo-controlled, crossover study.
Method:
A total of 406 patients with erectile dysfunction reported in their medical records who had completed external beam radiotherapy at least 6 months prior to the study, were approached by letter. Sixty patients were included in a study which lasted 12 weeks. They received 50 mg of sildenafil citrate or placebo for two weeks; during week 2 the dose could be increased to 100 mg in the case of unsatisfactory erectile response. At week 6 patients crossed over to the alternative treatment. Data were collected using the validated 'International index of erectile function' (IIEF) questionnaire, and side-effects were recorded. Patients were given the possibility of continuing to a 6-week open-label phase.
Results:
The mean age of those participating was 68 years. All patients completed the double-blind phase. For the majority f questions in the IIEF questionnaire, there was a significant increase in mean scores from baseline with sildenafil, but of the patients with sildenafil, versus 18% with placebo. Ninety percent of the patients required a dose adjustment to 100 mg sildenafil, and 100% of the patients in the placebo group increased the dose. Side-effects were mild or moderate. Patients who proceeded to the open-label phase reported the same results as in the double-blind phase.
Conclusion:
Sildenafil improved erectile function in about half of the patients with erectile dysfunction after external beam radiotherapy for prostate cancer, and it was well tolerated.
