DefinitionSeborrheic keratosis is noncancerous (benign) wart-like growths on the surface of the skin.Alternative NamesBenign skin tumors - keratosis; Keratosis - seborrheic; Senile keratosisCauses, incidence, and risk factorsSeborrheic keratosis is a benign form of skin tumor. The cause is unknown. The condition commonly appears after age 40.SymptomsSymptoms are skin growths that:Are located on the face, chest, shoulders, back, or other areasAre usually painless, but may become irritated and itchAre yellow, brown, black, or other colorsHave a slightly elevated, flat surfaceMay have a rough or wart-like textureOften have a waxy surfaceHave a round-to-oval shapeMay have a "pasted-on" appearanceMay be single, but are usually multiple growthsSigns and testsDiagnosis is based primarily on the a