a slowly developing, localized thickening and scaling of the outer layers of the skin consisting of hyperkeratotic papules and plaques as a result of chronic, prolonged exposure to the sun, also known as solar keratosis.
basal cell carcinoma
a malignant epithelial cell tumor arising from epidermal basal cells that begins as a papule and enlarges peripherally, developing a central crater that erodes, crusts, and bleeds.
the use of subfreezing temperatures to perform surgery.
scraping of material from the wall of a cavity or other surface using an instrument with a circular cutting edge attached to a handle, performed to remove tumors or other abnormal tissue or to obtain tissue.
nevi that are larger than usual (>5 mm across) with irregular borders and various shades of color; also known as atypical moles.
the thickening of the skin as a result of proliferation of keratinocytes with accentuation of the normal markings of the skin often caused by repeated scratching of a pruritic lesion.
a tumor arising in cells producing melanin, usually the melanocytes of the skin.
squamous cell carcinoma
a slow-growing malignant tumor of squamous epithelium; found in the lungs and skin and occurring also in the anus, cervix, larynx, nose, and bladder.
sunscreen protective factor (SPF ) index
a system of measuring the effectiveness of various formulations for protecting the skin from actinic rays of the sun.