It is commonly seen in women during pregnancy and after delivery. It may also be associated with the use of oral contraceptives and with the use of estrogens in postmenopausal women. Lesions become less prominent when a sunscreen is used to minimize UV exposure. Bleaching agents such as two to four percent hydroquinone in an opaque base may slowly improve the condition. Daily use of topical tretinoin may accelerate the response.
Early lesions resemble exaggerated skin lines or dirt on the skin surface.
Rare cases of generalized disease have occurred. Mucous membrane lesions and palmar and plantar keratoses are occasionally seen. The histologic appearance is nonspecific, consisting of hyperkeratosis in conjunction with papillomatosis and hyperpigmentation. The term acanthosis, which refers to an increase in thickness of the epidermis, is actually a misnomer. The disorder may be divided into so-called benign and malignant forms on the basis of whether it is associated with an internal malignant disorder.