Lichen sclerosus (LS) is a chronic scarring dermatosis of unknown etiology affecting individuals of all races. Lesions occur mostly on the genitalia, perineum, or perianal skin, but can appear anywhere.

LS presents as whitish plaques on the glans penis, prepuce, and shaft, frequently with subepidermal hemorrhages. If the glans penis and/or foreskin become involved, causing the tissues to shrink, the condition is called balanitis xerotica obliterans. The urethral meatus may also be involved. Although these lesions are mostly asymptomatic, there may be pruritus, burning on urination, meatal stenosis with difficulty voiding, phimosis, painful erections, diminished sensation of the glans, and sexual dysfunction.

Squamous cell carcinoma can arise in chronic, untreated genital lesions.