Sebaceous hyperplasia is a common, benign condition of sebaceous glands in adults of middle age or older. Lesions can be single or multiple and manifest as yellowish, soft, small papules on the face (particularly nose, cheeks, and forehead). Sebaceous hyperplasia occasionally also occurs on the chest, areola, mouth, foreskin.
Rarely reported variants have included a giant form, a linear or zosteriform arrangement, a diffuse form, and a familial form. Juxtaclavicular beaded lines are an additional variant characterized by closely placed papules arranged in parallel rows.Lesions of sebaceous hyperplasia are benign, with no known potential for malignant transformation, but may be associated with nonmelanoma skin cancer in transplantation patients.
Some authorities consider rhinophyma to represent a special form of sebaceous hyperplasia. Sebaceous glands are highly androgen sensitive, and, although the number of sebaceous glands remains approximately the same throughout life, their activity and size vary according to age and circulating hormone levels. The sebaceous glands, as well as the sweat glands, account for the vast majority of androgen metabolism in the skin.