Lichen sclerosus is a chronic and atrophic mucocutaneous condition affecting epidermis and dermal connective tissue that most commonly involves the genital and perianal skin in both males and females. Balanitis xerotica obliterans (BXO) is a term used as a synonym for lichen sclerosus of the glans penis and prepuce. This lesion has been found to be associated with penile carcinoma, and it has been postulated to be a preneoplastic condition for at least some types of penile cancers, particularly in non-human papilloma virus variants of squamous cell carcinoma.
BXO is commonly encountered in preputial resectates for phimosis in older men. In contrast, the prepubertal incidence in a series of 117 cases was only 4%. The idiopathic form of BXO is not associated with phimosis and presents with classic clinical and pathologic features. The cause of this classic form is unknown, but an autoimmune mechanism has been suggested.
Clinically, BXO presents as a well-defined and marginated white patch on the glans penis or prepuce that envelops or involves the urethral meatus. It may also present as a lichenoid scale with a roughened surface. In long-standing cases the lesion is firm due to underlying fibrosis, which may cause phimosis in uncircumcised men. Most lesions occur on the glans penis or prepuce, but occasionally the shaft is involved.
Histologically, active lesions of BXO show pronounced orthokeratotic hyperkeratosis accompanied by striking atrophy of the epidermis, a distinctive combination of features. Basal cell vacuolation and cleftinf of the dermoepidermal junction may also occur; in rare instances there may be bullae. The upper dermis is markedly edematous and the collagen forms a homogenized band, beneath which there may be a lymphoplasmacytic infiltrate.
The treatment of BXO is often difficult. Circumcision, laser therapy, and topical administration of steroids, antifungal agents, and retinoids have been used, with variable results.