Use of penile extender device in the treatment of penile curvature as a result of Peyronie's disease. Results of a phase II prospective study

Pilot experiences have suggested that tension forces exerted by a penile extender may reduce penile curvature as a result of Peyronie's disease. To test this hypothesis in a Phase II study using a commonly marketed brand of penile extender. Peyronie's disease patients with a curvature not exceeding 50 degrees with mild or no erectile dysfunction (ED) were eligible. Fifteen patients were required to test the efficacy of the device assuming an effect size of >0.8, consistent with an "important" reduction in penile curvature. Changes in penile length over baseline and erectile function (EF) domain scores of the International Index of Erectile Function (IIEF) constituted secondary end points. Patients were counselled on the use of the penile extender for at least 5 hours per day for 6 months. Photographic pictures of the erect penis and measurements were carried out at baseline, at 1, 3, 6, and 12 months (end of study). The IIEF-EF domain scores were administered at baseline and at the end of study. Treatment satisfaction was assessed at end of study using a nonvalidated institutional 5-item questionnaire. Penile curvature decreased from an average of 31 degrees to 27 degrees at 6 months without reaching the effect size (P = 0.056). Mean stretched and flaccid penile length increased by 1.3 and 0.83 cm, respectively at 6 months. Results were maintained at 12 months. Overall treatment results were subjectively scored as acceptable in spite of curvature improvements, which varied from "no change" to "mild improvement." In our study, the use of a penile extender device provided only minimal improvements in penile curvature but a reasonable level of patient satisfaction, probably attributable to increased penile length. The selection of patients with a stabilized disease, a penile curvature not exceeding 50 degrees, and no severe ED may have led to outcomes underestimating the potential efficacy of the treatment.