actinic keratosis


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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.

actinic keratosis

Senile keratosis, solar keratosis Dermatology A premalignant lesion of sun-exposed skin that is overly sensitive to the effects of UV light–sunlight, and more common in the fair-skinned or elderly Clinical Discrete scaly or gritty erythematous plaques located on a sun exposed surface Diagnosis Biopsy Management Cryosurgery or electrocautery; some topicals may be used to promote peeling Prognosis ± 20% of AKs develop into SCC Prevention Broad-spectrum sunscreens with a sun protection factor of 17 may ↓ new lesions; avoid photosensitizing drugs–eg, tetracyclines. See Squamous cell carcinoma.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

ac·tin·ic ker·a·to·sis

(ak-tin'ik ker'ă-tō'sis)
A premalignant warty lesion occurring on the sun-exposed skin of the face or hands in aged light-skinned people; hyperkeratosis may form a cutaneous horn, and squamous cell carcinoma of low-grade malignancy may develop in a small proportion of untreated patients. Treatment includes cryotherapy, surgical excision, or topical chemotherapy.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
Enlarge picture
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
See also: keratosis
Medical Dictionary, © 2009 Farlex and Partners

actinic keratosis

Local overgrowth and thickening of the EPIDERMIS of the skin caused by sunlight. This condition can progress to a form of skin cancer (SQUAMOUS CELL CARCINOMA) and is usually treated by freezing.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

Actinic keratosis

A crusty, scaly pre-cancerous skin lesion caused by damage from the sun. Frequently treated with cryotherapy.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.

ac·tin·ic ker·a·to·sis

(ak-tin'ik ker'ă-tō'sis)
A premalignant warty lesion occurring on the sun-exposed skin of the face or hands in aged light-skinned people.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Nast, "The natural history of actinic keratosis: a systematic review," British Journal of Dermatology, vol.
Our case poses new questions on the exact pathophysiology of actinic keratosis of the tarsal conjunctiva.
A randomized, double-blind clinical trial was performed on patients with actinic keratosis on the face or scalp from January 2010 to March 2011 in Sina hospital; the effect of cryotherapy alone, and Acnalen 0.1% gel with cryotherapy and placebo was studies in the treatment of actinic keratosis.
Utility of step sections: demonstration of additional pathological findings in biopsy samples initially diagnosed as actinic keratosis. Arch Dermatol.
Frequency of preexisting actinic keratosis in cutaneous squamous cell carcinoma.
Metvix is approved for non-melanoma skin cancer (basal cell carcinoma, BCC) and pre-cancerous skin lesions, actinic keratosis (AK), in most European countries and New Zealand, while market authorizations are pending in other countries.
For additional information on actinic keratosis, visit the following websites: aad.org (American Academy of Dermatology), skincancer.org (Skin Cancer Foundation), and/or aks.org (Actinic Keratosis Society).
Annoying lesions that peel or flake indicate actinic keratosis. Appearing on the head, neck and hands, the lesions are a precursor to cancer formation.
The results suggest a way to prevent progression from actinic keratosis to skin cancer.
Older adults should pay particular attention to the red, scaly patches of actinic keratosis occurring on the forehead, which can be precancerous.
Actinic keratosis and each of the skin cancers depicted in the following pages can be readily detected.