actinic keratosis

keratosis /ker·a·to·sis/ (ker″ah-to´sis) pl. kerato´ses   any horny growth, such as a wart or callosity.keratot´ic

---

actinic keratosis  a sharply outlined verrucous 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.

keratosis blennorrha´gica  keratoderma blennorrhagicum.

keratosis follicula´ris  a hereditary form marked by areas of crusting, itching, verrucous papular growths which may fuse to form papillomatous and warty malodorous growths.

inverted follicular keratosis  a benign usually solitary epithelial tumor originating in a hair follicle and occurring as a flesh-colored nodule or papule.

keratosis palma´ris et planta´ris  palmoplantar keratoderma.

keratosis pharyn´gea  that characterized by horny projections from the tonsils and the orifices of the lymph follicles in the pharyngeal walls.

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 tumor of epidermal origin, marked by soft friable plaques with slight to intense pigmentation, most often on the face, trunk, and limbs.

senile keratosis , solar keratosis actinic k.

---

actinic keratosis

n.

A warty lesion, often premalignant, occurring on the sun-exposed skin of the face or hands, especially of light-skinned persons. Also called senile keratosis.

---

Actinic keratosis

A crusty, scaly pre-cancerous skin lesion caused by damage from the sun. Frequently treated with cryotherapy.

Mentioned in: Cryotherapy, Skin Resurfacing

---

actinic keratosis,

a slowly developing, localized thickening and scaling of the outer layers of the skin as a result of chronic, prolonged exposure to the sun. It is more common in the fair skinned and elderly. It usually is a discrete, slightly raised, red-on-pink lesion located on a sun-exposed surface. Treatment of this premalignant lesion includes surgical excision, cryotherapy, and topical chemotherapy. Also called senile keratosis, senile wart, solar keratosis.

---

keratosis (ker´tō´sis),

n 1. a horny or cornified growth (e.g., wart, callosity).
n 2. a condition characterized by cornification, or hyperkeratinization, of the tissues.

keratosis, actinic,

n an overgrowth of the horny layer of the epidermis caused by excessive exposure to the sun.

keratosis blennorrhagia

(blen´rā´jē),
n a skin condition found in Reiter's syndrome characterized by pustules and crusting; once incorrectly associated with gonorrhea; more recently considered a genetic disorder occurring mostly in men between the ages of 20 and 25.

keratosis, chronic senile,

n keratosis of the lips in elderly individuals. These lesions should be considered precancerous.

keratosis, focal,

n localized areas of increased cornification (hyperkeratinization). Such lesions are seen particularly on the lips.

keratosis follicularis,

n See disease, Darier's.

keratosis, seborrheic (basal cell papilloma, verruca senilis)

(seb´rē´ik pap´lōm vroo´k sē´nilis),
n benign, pigmented, superficial epithelial tumors that clinically appear to be pasted on the skin of the trunk, arms, or face. Characterized histologically by marked hyperkeratosis, with keratin cyst formation, acanthosis of basal cells, and melanin pigmentation, all above the level of the adjacent epidermis.

keratosis, senile,

n small, firm lesions occurring principally on the face and back of the hands in elderly people or those exposed to the sun. There is hyperkeratosis with irregular and atypical proliferation of the cells of the rete Malpighi. The condition is one of premalignancy with tendency toward epidermoid carcinoma. See also leukoplakia.

---

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

see 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).

---

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.