The efficacy of dihydrotestosterone transdermal gel before primary hypospadias surgery: a prospective, controlled, randomized study.

PURPOSE

We sought to evaluate the efficacy of transdermal dihydrotestosterone treatment based on the results of hypospadias repair in children with primary hypospadias.

MATERIALS AND METHODS

A total of 75 randomized consecutive children who were a mean of 33.4 +/- 3.7 months old and had primary hypospadias were included in the study between September 2004 and April 2006. While 37 children were treated with 2.5% transdermal gel daily, applied directly onto the penile shaft and glans for 3 months (group 1), 38 children did not receive any treatment preoperatively (group 2). All children underwent hypospadias repair using tubularized incised plate urethroplasty. Postoperative complications were analyzed using the Mann-Whitney U test with respect to fistulas, urethral strictures, diverticula, meatal stenosis, glanular dehiscence and scar formation according to the results at 1-year followup.

RESULTS

Mean ages of the children in groups 1 and 2 were similar (30.8 +/- 5.4 months and 35.1 +/- 5.1 months, respectively). The urethral meatus was coronal in 70%, penile in 24% and penoscrotal in 5% of the patients in group 1, while it was coronal in 84% and penile in 16% of the patients in group 2. Postoperative complications included urethrocutaneous fistula in 4 patients (11%) in group 2, compared to 1 patient (3%) in group 1 (p >0.05). While 3 patients (8%) in group 2 had glanular dehiscence, no patient in the dihydrotestosterone group had this complication (p <0.05). There were 2 patients with meatal stenosis in group 2 (5%), and no patient with meatal stenosis in group 1 (p >0.05). In addition, there were 16 patients (42%) with moderate to severe postoperative scar formation in group 2, compared to only 2 patients (5%) in the dihydrotestosterone group (p <0.05). Finally, there was a significant difference between the overall reoperation rates of group 2 (9 patients, 24%) and group 1 (1 patient, 3%, p <0.05). None of our patients had signs or symptoms of urethral stricture or urethral diverticulum.

CONCLUSIONS

Pretreatment with dihydrotestosterone transdermal gel was effective in decreasing the complications and improving the cosmetic results after hypospadias repair.