The impact of intralesional interferon α-2b injection therapy on penile hemodynamics in men with Peyronie's disease

Introduction. Penile duplex Doppler ultrasound (PDDU) is currently the preferred method for the functional evaluation of penile hemodynamics. PDDU may be used to monitor objectively changes in penile vascular parameters in men who undergo treatment for Peyronie's disease (PD), including intralesional interferon alpha-2b (IFN alpha-2b). Aim. To investigate the impact of intralesional IFN alpha-2b therapy for PD on penile hemodynamics by using PDDU and to assess the objective role of PDDU in monitoring treatment outcomes. Materials and Methods. Thirty-nine patients (20 in the placebo and 19 in the IFN alpha-2b treatment arm) were enrolled in this prospective, placebo-controlled, parallel study. Patients received either 10 mL saline or 5 x 10(6) units of IFN alpha-2b intralesional injections every other week for a total of six injections. Patients in each group were evaluated at baseline and after completion of treatment regarding changes in penile hemodynamic parameters, penile curvature, plaque size and density, pain on erection, and erectile function. Specific published criteria were used for PDDU measurements. Outcomes were statistically compared between each group by using Mann-Whitney U and chi-square tests. Results. The mean age of the patients and the duration of PD were similar in both groups. The improvement in penile blood flow was significantly greater in IFN (alpha-2b-treated patients than those in the placebo group. The number with the nonvascular classification increased significantly in the IFN alpha-2b arm from 31.5% to 57.8%. Additionally, improvements in penile curvature, plaque size and density, and pain on erection were better in the IFN alpha-2b group compared with the control. No significant improvement was observed in the erectile function domain in either group. Conclusion. This study reveals that intralesional IFN a-2b injections have a significant benefit on penile hemodynamic parameters. Moreover, intralesional IFN alpha-2b is an effective, minimally invasive treatment for PD, and PDDU is a useful adjunct to monitor objectively changes in penile vascular parameters.