Peyronie’s disease

Urologists Mr Suks Minhas and Dr Kuo J Ho update GPs on the causes and treatments of Peyronie's disease

Peyronie's disease is a benign penile condition – also known as induratio penis plastic or chronic inflammation of tunica albuginea. The clinical features are presence of plaque within the tunica albuginea – a fibrous envelope surrounding the penile corpora cavernosa – causing deformity and pain. It causes erectile dysfunction in 40-50% of cases.

Estimates of prevalence range from 1-4% of men, although in one US study urologists screening men for prostate cancer put the prevalence at almost 9%.1 Two-thirds of cases present in men aged between 40 and 60 years and the condition most commonly presents in Caucasian males.

Pathophysiology

Penile plaques are most commonly found dorsally. During erection, the underlying corpus cavernosum is unable to stretch fully, causing penile curvature or rotation. Cavernosal fibrosis can also cause distal flaccidity or an unstable penis.

There are two phases to the condition. The active phase – between one and six months from disease onset – is characterised by increasing plaque size or penile curvature and pain. Some men will experience continued progression after six months. One goal of medical therapy is to shorten the acute phase of disease to promote stabilisation of the plaque and decrease progression of disease. The quiescent phase of disease – which usually starts nine to 12 months after onset – is characterised by the absence of penile pain and a period of unchanging curvature or plaque size.

Natural history

Left alone, about 12-13% of patients will spontaneously improve over time, 40-50% will get worse and the rest will be relatively stable.2 In the largest study to date of the disease, all the men who initially had pain reported improvement and 89% reported complete resolution. Of the men with significant curvature, 12% improved, 40% remained stable and 48% worsened. The mean change in curvature was 12° in those who had improved and 22° in those who had worsened.3

Aetiology

Although the exact cause is unknown, repeated minor sexual trauma is a possibility, due to microvascular injury and bleeding into the tunica causing inflammation and fibrosis.

Up to 40% of men with Peyronie's develop fibrosis in other elastic tissues of the body, such as on the hand or foot, including Dupuytren's contracture of the hand. An increased incidence in genetically related males suggests a genetic component.

There are also associations with plantar fascial contracture, diabetes, arterial disease and blood group A+. The disease is also associated with drugs like calcium channel blockers and ß-blockers.

Assessment

Include sexual history and examination of genitalia – including location and size of plaque and any tenderness. On referral, deformity can be documented by inducing an artificial erection in clinic, but GPs could ask patients to supply a digital image to assess the extent of the problem. Doppler ultrasound can be used to assess vascular abnormalities and MRI imaging is sometimes used to assess complex or extensive cavernosal fibrosis.

Treatment

Medical treatment is the mainstay in the condition's active phase and surgery in the stable quiescent phase.4

Medical treatment

Various oral medications have been tried, including:

• vitamin E 200mg three times a day for three months

• tamoxifen 20mg twice daily for three months

• colchicine 500mg three times a day for six weeks

• potassium para-aminobenzoate (Potaba) 12g daily in divided doses after food.

Overall, the evidence base isn't strong. Other agents tried include L-carnitine, L-arginine, and sildenafil. The vasodilator pentoxifylline has also been studied – it works by inhibiting transforming growth factor, which is involved in the fibrosing process.

Intralesional injections into penile plaques with verapamil may be effective in some patients. More recently treatment approved by the US Food and Drug Administration for Dupuytren's contracture has been reported to break down the excess collagen that causes Peyronie's disease, although is not licensed for this use.

Surgical treatment

Surgery is used as a last resort for the most severely affected patients.4

• Nesbit's procedure – the penis is degloved via a subcoronal incision with or without circumcision. An artificial erection is then induced intraoperatively with saline and an ellipse of tissue excised on the opposite side of maximal deformity – which is then closed with absorbable sutures.

• Lue procedure – this procedure involves plaque incision and venous grafting. An H-shaped incision is made in the penis and a venous patch or artificial graft is placed to lengthen the affected side.

Penile implants can be used for severe deformities with erectile dysfunction.

Mr Suks Minhas is a consultant urologist and andrologist and honorary senior lecturer at the Institute of Urology and University College Hospital, London

Dr Kuo J Ho is a clinical fellow in urology at University College Hospital, London