A 65-year-old man noted a new growth on his face for 1 year (Figure 165-1A). On close examination, the growth was pearly with a few telangiectasias. The donut shape and presence of sebaceous hyperplasia scattered on other areas of the face were reassuring that this is likely a benign sebaceous hyperplasia. To confirm our clinical impression, the lesion was examined with a dermatoscope (Figure 165-1B). Vessels extending toward the center of the lesion from the periphery but not crossing the center (like the shape of a crown) were seen. This along with the yellow color of the sebaceous glands strongly supported the diagnosis. Because the patient wanted the lesion to be removed, a shave biopsy was performed to completely rule out basal cell carcinoma (BCC). The patient was happy with the cosmetic result and relieved that the pathology showed sebaceous hyperplasia.
A. Large single lesion of sebaceous hyperplasia that was examined by dermoscopy to confirm that it was not a basal cell carcinoma. B. Typical features of sebaceous hyperplasias were seen (crown vessels among yellow sebaceous glands). (Reproduced with permission from Richard P. Usatine, MD.)
Sebaceous hyperplasia (SH) is a common, benign condition of sebaceous glands consisting of multiple asymptomatic small yellow papules with a central depression. The sebaceous lobules of SH are greater in number and higher in the dermis than normal sebaceous glands, and only 1 gland appears enlarged.1 Consequently, the term hyperplasia appears to be a misnomer, and SH is more accurately classified as a hamartoma (disorganized overgrowth of tissue normally found at that site).1
SH occurs in approximately 1% to 26% of the adult population; the latter number is from a population study of hospitalized patients with a mean age of 82 years.1
The prevalence of SH is increased in those with immunosuppression by 10-fold to 30-fold1; for example, 10% to 30% of patients receiving long-term immunosuppression with cyclosporine have SH.2,3
SH has also been reported in infants, where they are considered physiologic,4 and in young adults who may have a family history of SH.1
SH has been reported overlying other skin lesions including neurofibromas, melanocytic nevi, verruca vulgaris, and skin tags.1
Rare forms of SH include giant linear (up to 5 cm in diameter) and functional familial (also called premature or diffuse SH); the latter occur typically around puberty as thick plaque-like lesions with pores resembling an orange peel.1
ETIOLOGY AND PATHOPHYSIOLOGY
Sebaceous glands, a component of the pilosebaceous unit, are found throughout the skin, everywhere that hair is found. The greatest number is found on the face, chest, back, and upper outer arms.
The glands ...