Cutaneous oncocytoma – a report of three cases and review of the literature

Abstract

The oncocyte is a cell characterized by capacious, eosinophilic, finely granular cytoplasm, and lesions composed primarily of oncocytes are termed oncocytomas. Whereas oncocytic metaplasia has been reported in various cutaneous neoplasms, oncocytomas typically occur in the kidneys, thyroid and salivary glands and are uncommon in the dermatopathology literature. We present three cases of cutaneous oncocytoma so that dermatopathologists are cognizant of this uncommon entity. Although some believe that oncocytomas are locally aggressive lesions, our cases indicate that their clinical course is perhaps as banal as their histology.

Syringometaplasia: variants and underlying mechanisms

“…It has been described as a rare cutaneous neoplasm (cutaneous oncocytoma), as well as a focal change in several cutaneous neoplasms, such as eccrine acrospiroma, porocarcinoma, and melanocytic nevi. However, it is currently believed to be a neoplastic rather than a metaplastic change …”

Periocular cutaneous oncocytoma with signs of disrupted oxygen metabolism

“…Oncocytic tumors of the ocular adnexa are very rare, being first described in the lacrimal gland, and most cases occur at the caruncula between the upper and lower puncta . Periocular oncocytoma arising from the outer skin surface, as in our case, or cutaneous oncocytoma of extraocular sites occur only exceptionally.…”

“…Glandular structures of either apocrine or eccrine origin are reputed to underly these cases . However, exceptions to the postulated ductular histogenesis may exist, and metaplastic change of stratified squamous epithelium may likewise lead to the formation of oncocytoma. In our case, focal connection of the oncocytoma to the epidermis could be detected, and a clear‐cut transition of normal epidermis to oncocytic metaplasia was observed.…”

Extramammary Paget Disease of Scrotum With Oncocytic Changes

“…This requirement has not always been followed, because cutaneous oncocytomas have been reported based solely on cell characteristics, with no demonstration of the presence of mitochondria. 8 Oncocytic changes should not be confused with the eosinophilic granular changes observed in different cutaneous tumors (eg, basal cell carcinoma, malignant melanoma, leiomyosarcoma, and granular cell tumor), [9][10][11][12] in which there is no increase in mitochondria.…”

“…However, they are highly infrequent in cutaneous disease, with only a few reports of oncocytic changes in eccrine acrospiroma, nodular hydradenoma, porocarcinoma, melanocytic nevus, and cutaneous oncocytoma. [3][4][5][6][7][8] Oncocytic cells are characterized by a wide, eosinophilic, and granular cytoplasm with abundant mitochondria. Besides the presence of these features, the definitive diagnosis of oncocytic changes requires detection of an increase in mitochondria using ultrastructural and/or immunohistochemical techniques.…”