Cutaneous Adenolipoma: Extending the Spectrum of Changes in the Lipomatous and Epithelial Components

Adenolipoma refers to a variant of a lipoma with entrapped eccrine or, rarely, apocrine units. We present 5 cases of cutaneous adenolipoma to demonstrate the spectrum of changes in the lipomatous and epithelial components. The cases include 3 lesions having a conventional lipomatous element and 1 with a spindle cell lipomatous component, each additionally featuring entrapped minimally altered eccrine units. In the remaining case, the epithelial component manifested a combination of hyperplastic and metaplastic changes (clear cell and squamous metaplasia) and unusually altered polarity of luminal cells with expression of myoepithelial cell markers on the luminal cells while focal absence of basal/myoepithelial cell in the corresponding area as evident microscopically and immunohistochemically.