solar keratosis

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Related to solar keratosis: seborrheic keratosis, solar lentigo


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.

ac·tin·ic ker·a·to·sis

a premalignant warty lesion occurring on the sun-exposed skin of the face or hands in aged light-skinned persons; hyperkeratosis may form a cutaneous horn, and squamous cell carcinoma of low-grade malignancy may develop in a small proportion of untreated patients.

solar keratosis

actinic keratosis

A premalignant lesion of sun-exposed skin that is overly sensitive to the effects of UV light (i.e., sunlight), and more common in the fair-skinned or elderly, and the immunocompromised.
Cryosurgery, photodynamic therapy, laser (CO2, Er:YAG), electrocautery; some topical immune response modifiers (e.g., 5FU) may be used to promote peeling.
± 20% of AKs develop into squamous cell carcinoma.

Broad-spectrum sunscreens with a sun protection factor of 17 may reduce new lesions; avoid photosensitising drugs (e.g., tetracyclines); in subjects with AK placed on a low-fat diet, the incidence of new lesions fell to 1⁄3 that of the control (non-diet intervention) group. HPV replication is thought to play a role in malignant changes.


(ker?a-to'sis) (-to'sez?) plural.keratoses [ kerato- + -osis]
1. Growth of the horny layer of the skin; a callus, callosity, or keratoma.
2. Any condition of the skin characterized by the formation of horny growths or excessive development of the horny growth. keratotic (?a-tot'ik), adjective Synonym: keratoma
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ACTINIC KERATOSIS: Actinic skin damage on forehead and scalp

actinic keratosis

Abbreviation: AK
A rough, sandpaper-textured, premalignant macule or papule caused by excess exposure to ultraviolet light. AKs often appear on facial skin (such as near the eyes, on the nose, on the ears, or the lips) and the parts of the body that receive the most sunlight exposure. Prevention of AKs depends on limiting one's exposure to sunlight, beginning in childhood and continuing throughout life. See: illustration


Liquid nitrogen destroys these lesions and prevents them from progressing to other cancers of the skin.

Synonym: solar keratosis See: sunscreen

keratosis follicularis

Darier's disease.

keratosis nigricans

Acanthosis nigricans.

oral keratosis

Keratinization of the mucosa of the mouth to an unusual extent, or in locations normally not keratinized, as a result of an inherited autosomal dominant gene or the more common effect of tobacco and other carcinogens.

keratosis palmaris et plantaris

A congenital abnormality of the palms and soles, characterized by a dense thickening of the keratin layer in these regions.

keratosis pharyngis

Horny projections from the pharyngeal tonsils and adjacent lymphoid tissue.

keratosis pilaris

Chronic inflammatory disorder of area surrounding the hair follicles. It is often found in patients with atopic dermatitis. Synonym: lichen pilaris; lichen spinulosus


The disorder is characterized by an accumulation of horny material at follicular orifices of persons with rough, dry skin. It is most pronounced in winter on lateral aspects of thighs and upper arms with possible extension to legs, forearms, and scalp.


There is no specific therapy, but keratolytic lotions may be of some value.

keratosis punctata

Discrete horny projections from the sweat pores of the palms and soles.
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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.


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.


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

keratosis senilis

An inaccurate synonym for actinic keratosis, which is caused by accumulated ultraviolet light exposure, not by aging.

smokeless tobacco keratosis

Tobacco pouch keratosis.

snuff keratosis

Tobacco pouch keratosis.

solar keratosis

Actinic keratosis.
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STUCCO KERATOSIS: White warty lesions of the dorsum of the fist

stucco keratosis

Benign papules, typically found on the lower extremities, histologically related to seborrheic keratoses. See: illustration

tobacco pouch keratosis

A white, corrugated lesion found on the oral mucosa usually in the muccobuccal fold where chewing tobacco has been habitually placed.
Synonym: smokeless tobacco keratosis; snuff keratosis


any horny growth on the skin, such as a wart or callosity; a firm, elevated, circumscribed area of excessive keratin production. Common in humans but uncommon in animals.

actinic keratosis
varies from a sharply outlined verrucous or keratotic growth to poorly defined areas of erythema, which are premalignant lesions. Due to excessive exposure to the sun. Called also solar keratosis.
equine cannon keratosis
linear keratosis
see equine linear keratosis.
keratosis pilaris
hyperkeratosis limited to the hair follicles.
seborrheic keratosis, keratosis seborrheica
single or multiple elevated plaques and nodules often hyperpigmented with a hyperkeratotic greasy surface. They are benign, of unknown etiology, but have no connection with seborrhea. Occur in dogs and humans.
solar keratosis
see actinic keratosis (above).


emanating from or pertaining to the sun's rays.

solar burn
see sunburn.
solar dermatitis
see solar dermatitis.
solar elastosis
degenerative changes in the dermis caused by excessive solar radiation.
solar keratosis
see actinic keratosis.
nasal solar dermatitis
see solar dermatitis, collie nose.
References in periodicals archive ?
Solar keratosis is one of the most treatable forms of sun damage - consult your GP immediately about anything you are concerned about.
An estimated 345 new cases of solar keratosis are diagnosed every month in Wales by dermatologists and up to 20% of patients with solar keratosis go on to develop squamous cell carcinoma, one of the most common, but most treatable types of skin cancer.
Believed to have an incidence rate of 2-3 times that of BCC, AK or Solar Keratosis as it is known in some countries, is a sun-induced, precancerous skin condition which unlike BCC also affects non-Caucasian skin types.
Robert Rosen, a Sydney dermatologist and scientific advisor to Peplin, who has also been involved in the PEP005 clinical trial program, said that current treatment options for solar keratosis have a number of shortfalls, including pain, persisting skin irritation and redness during prolonged treatment periods.
An actinic keratosis, also known as solar keratosis, is a scaly or crusty bump that arises on the skin surface.