Adenolipoma of the Skin Arising at Neck Region

We report here a case of adenolipoma of the skin, an unusual variant of lipoma, arising on the neck. A 56-year-old man visited our hospital due to an anterior neck mass. An excisional biopsy was performed. The mass revealed a tan-yellow soft cut surface. We could not find any difference from other lipoma on gross inspection. Microscopically, the mass showed proliferation of mature adipocytes admixed with several eccrine units. The eccrine units were demonstrated by periodic acid-Schiff-positive granules in the secretory portions and by positivity of smooth muscle actin in the myoepithelial cells surrounding the eccrine glands. The tumor was completely excised, and the patient has been followed up without any evidence of recurrence so far.