Clinical Efficacy of Injection and Mechanical Therapy for Peyronie's Disease: A Systematic Review of the Literature.

Context: Conservative therapies for Peyronie's disease (PD) aim to treat early-stage disease by improving clinical outcomes such as penile curvature, penile length erectile dysfunction, and pain.

Objective: To summarise the available evidence regarding injection and mechanical therapies for PD treatment.

Evidence Acquisition: An extensive search of Medline, Embase, and Scopus databases retrieved English-language articles up to 15 May 2018. The systematic review protocol was registered on PROSPERO (CRD42017077050). Inclusion criteria were as follows: adults with early or chronic PD receiving treatment with injection therapy, penile traction, or a vacuum device.

Evidence Synthesis: Fifty-two articles were selected according to the inclusion criteria-17 comparative studies and 35 cohort studies-analysing the effects of calcium channel blockers (verapamil, nicardipine), collagenase Clostridium histolyticum (CCH), interferon α-2b (IFNα-2b), hyaluronic acid (HA), onabotulinum toxin A, thiocolchicine, penile extender devices, and vacuum devices. Qualitative data from these studies suggest a clinically significant effect of CCH and IFNα-2b injection therapy to decrease penile curvature and conserve penile length. Verapamil and HA performed well in single-arm or case-control studies. Studies of penile traction and vacuum devices in patients with PD demonstrated some benefits in terms of curvature and penile length but only in small, underpowered, nonrandomised studies. Studies of onabotulinum toxin A injections or thiocolchicine showed significant improvements in penile curvature, but only in studies of single-arm or case-control design.

Conclusions: CCH and IFNα-2b injected into stable PD plaques can decrease penile curvature; CCH can also improve penile length. However, based on available data, strong conclusions cannot be drawn for other treatments, including calcium channel blockers, HA, or mechanical therapies.

Patient Summary: Our systematic review of injection therapies provides evidence for improvements in penile curvature for patients with Peyronie's disease. No robust evidence is available to support the use of other local treatments including calcium channel blockers, hyaluronic acid, or mechanical therapies.