Borderline Malignant Sebaceoma of the Auricle: A Case Report

Abstract

Sebaceoma is a rare benign tumor arising from the sebaceous gland of the skin. Sebaceoma often occurs on the head and neck but rarely on the ears. We present the case of a 78-year-old female patient with a two-year history of a protruding mass in her left ear. Physical examination revealed a well-circumscribed plaque in the crus of the helix of the left ear. A wide local excisional biopsy was taken, and the mass was subjected to histopathologic assessment. While the mass showed cytological findings indicating sebaceoma, it also presented malignant features architecturally and immunohistochemically. Based on these findings, the tumor was regarded as a sebaceoma of borderline malignancy.

Supplementary information: The online version contains supplementary material available at 10.1007/s12070-023-03552-4.

Keywords: Ear Auricle; Malignancy; Sebaceoma; Sebaceous Gland.

Fig. 1

A solitary flesh-colored mass on the left ear’s crus helix. The mass was focally covered with crust

Fig. 2

A. A well-circumscribed protruding solid tumor, mainly composed of monomorphic basaloid cells (hematoxylin and eosin, original magnification x10). B. Higher power revealed dermal aggregates of basaloid cells (arrow) admixed with mature sebaceous cells and fat vacuoles (*) (hematoxylin and eosin, original magnification x200)

Fig. 3

Local dermal invasion of the tumor (arrow) (hematoxylin and eosin, original magnification x40)

Fig. 4

Immunohistochemical stains (A, p-53, original magnification, x100, B, Ki-67, original magnification, x200) show mild expression