[Favorable effect of sildenafil on erectile dysfunction in patients after radiotherapy for prostate cancer; randomised, double-blind, placebo-controlled crossover study].
OBJECTIVE
To determine the efficacy of sildenafil in patients with erectile dysfunction after external beam radiotherapy for prostate cancer.


METHODS
Randomised, double-blind, placebo-controlled, crossover study.


METHODS
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.


CONCLUSIONS
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.
Incrocci
L
L
Erasmus Medisch Centrum, Daniel den Hoed Kliniek, Rotterdam, Netherlands. l.incrocci@erasmusmc.nl
Hop
W C J
WC
Slob
A K
AK
D000368:Aged; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D007172:Erectile Dysfunction / Q000188:drug therapy* / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000008:administration & dosage / Q000627:therapeutic use*; D011471:Prostatic Neoplasms / Q000150:complications / Q000532:radiotherapy*; D011687:Purines; D011832:Radiation Injuries / Q000188:drug therapy* / Q000209:etiology; D000068677:Sildenafil Citrate; D013450:Sulfones; D011795:Surveys and Questionnaires; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000627:therapeutic use*
D010879:Piperazines; D011687:Purines; D013450:Sulfones; D014665:Vasodilator Agents; D000068677:Sildenafil Citrate