• A precancerous lesion of the skin composed of atypical keratinocytes. It is characterized by the presence of thick, scaly patches of skin. Several histologic variants have been described, including atrophic, acantholytic, and hyperkeratotic variants.
  • A thick, scaly patch of skin that may become cancer. It usually forms on areas exposed to the sun, such as the face, scalp, back of the hands, or chest. It is most common in people with fair skin.
  • Precancerous thick and scaly patches of skin
  • White or pink lesions on the arms, hands, face, or scalp that arise from sun-induced dna damage to keratinocytes in exposed areas. They are considered precursor lesions to superficial squamous cell carcinoma.