solar keratosis


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Related to solar keratosis: seborrheic keratosis, solar lentigo

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.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

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.
Farlex Partner Medical Dictionary © Farlex 2012

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.
 
Diagnosis
Biopsy.
 
Management
Cryosurgery, photodynamic therapy, laser (CO2, Er:YAG), electrocautery; some topical immune response modifiers (e.g., 5FU) may be used to promote peeling.
 
Prognosis
± 20% of AKs develop into squamous cell carcinoma.

Prevention
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.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

keratosis

(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

Treatment

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

Symptoms

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.

Treatment

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 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

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
Medical Dictionary, © 2009 Farlex and Partners
References in periodicals archive ?
Most of the damaging effects, such as sunburn, pigmentation, photoaging, solar keratosis, skin cancer (carcinoma and melanoma) and immuno-suppression have been attributed to UV radiation (290-400 nm).
TABLE 1 Lesion-directed therapy: Physical treatments for actinic keratoses Curettage and Cryotherapy Electrodesiccation Description Destroys solar keratosis Based on the difference which resides in the in feel between tumor epithelium (friable, easily scraped away) and healthy dermal Use requires experience tissue.
The important consideration in these cases is not the horn, but the underlying pathology which may be benign (Seborrheic keratosis, viral warts, histiocytoma, inverted follicular keratosis, verrucous epidermal nevus, molluscum contagiosum, etc.), premalignant (Solar keratosis, arsenical keratosis, Bowen's disease) or malignant (Squamous cell carcinoma, rarely basal cell carcinoma, metastatic renal carcinoma, granular cell tumour, sebaceous carcinoma or Kaposi's sarcoma.
A quantitative immunohistochemical evaluation of lentigo maligna and pigmented solar keratosis. Am J Clin Pathol.
In both cancer types - squamous cell carcinoma (SSC) and pre-malignant solar keratosis (SK) - the basal skin layer harboured more UVA than UVB fingerprints.