seborrheic keratosis

keratosis

 [ker″ah-to´sis]

any horny growth, such as a wart or callosity.

actinic keratosis a sharply outlined wartlike or keratotic growth, which may develop into a cutaneous horn, and may become malignant; it usually occurs in the middle aged or elderly and is due to excessive exposure to the sun. Called also senile or solar keratosis. (See Atlas 3, Part F).

keratosis follicula´ris a slowly progressive autosomal dominant disorder of keratinization characterized by pinkish to tan or skin-colored papules on the seborrheic areas of the body that coalesce to form plaques, which may become crusted and secondarily infected; over time, the lesions may become darker and may fuse to form papillomatous and warty malodorous growths. Called also Darier's disease and Darier-White disease.

keratosis palma´ris et planta´ris palmoplantar keratoderma.

keratosis pharyn´gea horny projections from the tonsils and pharyngeal walls. Called also pharyngokeratosis.

keratosis pila´ris hyperkeratosis limited to the hair follicles.

keratosis puncta´ta a hereditary hyperkeratosis in which the lesions are localized in multiple points on the palms and soles.

seborrheic keratosis (keratosis seborrhe´ica) a benign, noninvasive tumor of epidermal origin, marked by numerous yellow or brown, sharply marginated, oval, raised lesions.

senile keratosis (solar keratosis) actinic keratosis.

seb·or·rhe·ic ker·a·to·sis

, keratosis seborrheica

superficial, benign, verrucous, often pigmented, greasy lesions consisting of proliferating epidermal cells, resembling basal cells, enclosing horn cysts; they usually occur after the third decade.

Synonym(s): basal cell papilloma, seborrheic verruca

seborrheic keratosis

Senile keratosis Dermatology A benign, often numerous lesion of the face and upper trunk of older adults, which appear as wart-like growths in various colors; SKs may become irritated and itch because of friction from clothes. See Keratosis.

seb·or·rhe·ic ker·a·to·sis

, keratosis seborrheica (seb'ōr-ē'ik ker'ă-tō'sis, seb-ōr-ē'i-kă)

1. A superficial, benign, verrucous, often pigmented, greasy lesion consisting of proliferating epidermal cells, resembling basal cells, enclosing horn cysts; usually occur after the third decade.

2. Synonym(s): senile keratosis. Synonym(s): seborrhoeic keratosis.

SEBORRHEIC KERATOSES ON BACK

seborrheic keratosis

A benign skin tumor that may be pigmented. It is composed of immature epithelial cells and is quite common in older adults. Its etiology is unknown.

Symptoms

Keratoid, nevoid, acanthoid, or verrucose types occur in older adults and in those with long-standing dry seborrhea, on the face, scalp, interscapular or sternal regions, and backs of the hands. The yellow, gray, or brown sharply circumscribed lesions are covered with a firmly adherent scale, greasy or velvety on the trunk or scalp but harsh, rough, and dry on the face or hands.

Treatment

Thorough curettage is effective. This leaves a flat surface that becomes covered with normal skin within about 1 week. Pedunculated lesions can be removed surgically. Cautery may produce scarring and should not be used.

Synonym: wart, seborrheic See: illustration

See also: keratosis

seb·or·rhe·ic ker·a·to·sis

, keratosis seborrheica (seb'ōr-ē'ik ker'ă-tō'sis, seb-ōr-ē'i-kă)

Superficial, benign, verrucous, often pigmented, greasy lesions consisting of proliferating epidermal cells, resembling basal cells, enclosing horn cysts; usually occur after the third decade.
Synonym(s): basal cell papilloma.