|
Actinic cheilitis (abbreviated to AC, also termed actinic cheilosis, actinic keratosis of lip, solar cheilosis,〔 sailor's lip, farmer's lip), is cheilitis (lip inflammation) caused by long term sunlight exposure. Essentially it is a burn,〔 and a variant of actinic keratosis which occurs on the lip.〔 It is a premalignant condition, as it can develop into squamous cell carcinoma (a type of mouth cancer). ==Signs and symptoms== AC almost always affects the lower lip and only rarely the upper lip, probably because the lower lip is more exposed to the sun. In the unusual cases reported where it affects the upper lip, this may be due to upper lip prominence.〔 The commissures (corners of the mouth) are not usually involved.〔〔 Affected individuals may experience symptoms such as a dry sensation and cracking of the lips.〔 It is usually painless and persistent. The appearance is variable. White lesions indicate hyperkeratosis.〔 Red, erosiive or ulcerative lesions indicate atrophy, loss of epithelium and inflammation.〔 Early, acute lesions may be erythematous (red) and edematous (swollen).〔 With months and years of sun exposure, the lesion becomes chronic and may be grey-white in color and appear dry, scaly and wrinkled.〔 There is thickening whitish discoloration of the lip at the border of the lip and skin. There is also a loss of the usually sharp border between the red of the lip and the normal skin, known as the vermillion border. The lip may become scaly and indurated as AC progresses. When palpated, the lip may have a texture similar to rubbing the gloved finger along sandpaper.〔 AC may occur with skin lesions of actinic keratosis or skin cancer elsewhere, particularly on the head and neck〔 since these are the most sun exposed areas. Rarely it may represent a genetic susceptibility to light damage (e.g. xeroderma pigmentosum or actinic prurigo).〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Actinic cheilitis」の詳細全文を読む スポンサード リンク
|