Zoon's balanitis (balanitis circumscripta plasmacellularis).

The clinical and histopathological features of nineteen cases of Zoon's balanitis and a comparable lesion of the vulva have been reviewed. The condition is particularly distinguished by characteristic histological changes affecting the epidermis and the dermal vasculature. The presence of a plasma cell infiltrate is relatively non-specific. Recognition of these features should allow simple differentiation from premalignant, infective and other inflammatory penile lesions which may be more responsive to treatment.