Recovery of spontaneous erectile function after nerve-sparing radical retropubic prostatectomy with and without early intracavernous injections of alprostadil: results of a prospective, randomized trial.

PURPOSE: This study was aimed at assessing prospectively the effect of postoperative intracavernous injections of alprostadil on the recovery of spontaneous erectile function after nerve-sparing radical retropubic prostatectomy.

MATERIALS AND METHODS: A total of 30 potent patients with clinically localized prostate cancer (clinical stage B1 or B2, Gleason sum 7 or greater, prostatic specific antigen less than 20 ng./ml.) underwent nerve-sparing radical retropubic prostatectomy and was subsequently randomized to alprostadil injections 3 times per week for 12 weeks (group 1, 15 patients) or observation without any erectogenic treatment (group 2, 15 patients). Patients were assessed at the 6-month followup by sexual history, physical examination, color Doppler sonography of the cavernous arteries and polisomnographic recording of nocturnal erections.

RESULTS: In group 1, 12 patients (80%) completed the entire treatment schedule and were evaluated at the long-term followup. Eight patients in this group (67%) reported the recovery of spontaneous erection sufficient for satisfactory sexual intercourse, compared with 3 patients (20%) in group 2. The difference between the 2 groups was statistically significant (p <0.01). In group 1, all but 1 patient reporting normal postoperative erections also showed normal erections at nocturnal testing, whereas color Doppler sonography demonstrated normal penile hemodynamics in all of them. In these patients, failures were the result of cavernous veno-occlusive dysfunction (2 cases, 17%) and cavernous nerve injury (2 cases, 17%). In group 2, patients with normal erections showed both normal nocturnal testing and penile hemodynamics, whereas failures were the result of cavernous veno-occlusive dysfunction (8 cases, 53%), cavernous arterial insufficiency (2 cases, 13%) or cavernous nerve injury (3 cases, 20%). Complications in patients treated with alprostadil injections accounted for 2 cases (13%) of a penile nodule and 1 further case (6%) of prolonged penile erection. Complications were not seen in group 2 patients.

CONCLUSIONS: Early postoperative administration of alprostadil injections significantly increases the recovery rate of spontaneous erections after nerve-sparing radical retropubic prostatectomy. It is our belief that programmed vasoactive injections improve cavernous oxygenation, thereby limiting the development of hypoxia-induced tissue damage. The potential complications related to the use of intracavernous injections must be clearly explained to patients.