Penile fibromatosis presents as a plaque or hard lump in the layers of erectile tissue that occurs more often on the upper than lower side of the penis. Mild cases may just appear as redness and swelling (inflammation), whilst in more severe cases hardened plaques force the penis to bend during erection, which may be painful.
Penile fibromatosis is also known as plastic induration of the penis and Peyronie disease.
Who gets penile fibromatosis?
Penile fibromatosis occurs in men aged between 30 and 80 years, with most occurrences between 40 and 60 years.
What causes penile fibromatosis?
The cause of penile fibromatosisis unknown but may be related to atherosclerosis (hardening of the arteries). Under the microscope fibrosis (scarring) is present in the connective tissue in the deeper layers of the penis between the corpus cavernosum and the tunica albuginea.
Penile fibromatosis may have genetic associations but reliable studies are lacking.
What are the signs and symptoms of penile fibromatosis?
Penile fibromatosis signs and symptoms include the following.
Erections may be painful.
The erect penis may bend.
A lump is found under the skin of the penis. The lump may be 0.6–6 cm in diameter.
A fibrous plaque may form on both the top and bottom, causing the erect penis to have an hourglass shape with a floppy tip.
What treatment is available for penile fibromatosis?
In many men, penile fibromatosis is mild and resolves within a year or two so treatment may be unnecessary. In more severe cases, the hardened lump and deformity persist and may get worse.
Medical therapy with various agents may relieve the discomfort e.g. Vitamin E, intralesional steroids or ultrasonic therapy but these seldom help long-term. Intralesional collagenase clostridium histolyticum (marketed as Xiaflex®) may be helpful.
Surgery is probably the best treatment but is usually only done after waiting for 1–2 years to allow the plaque to stabilise or disappear. There is less chance of recurrence after surgery if the inflammatory phase of penile fibromatosis has settled and the degree of bending has reached its peak. A semi-rigid prosthesis may be inserted.
A penis enlargement medical device may also reduce the penile curvature and risk of retraction after a penile surgery.
Book: Textbook of Dermatology. Ed Rook A, Wilkinson DS, Ebling FJB, Champion RH, Burton JL. Sixth edition. Blackwell Scientific Publications