Work

Benign Parotid Myoepithelioma: A Diagnostic Chameleon Masquerading as Pleomorphic Adenoma and the Critical Role of Immunohistochemistry

Year: 2025

Type: article

Abstract: Myoepithelioma is a rare benign salivary gland tumor (<1%) that poses a significant diagnostic challenge by perfectly mimicking pleomorphic adenoma on imaging. We report a case of a 56-year-old male with a slow-growing, painless left parotid mass. MRI findings were typical for pleomorphic adenoma. The patient underwent superficial parotidectomy. Histopathology revealed a proliferation of myoepithelial cells, and immunohistochemistry (p63+, CK7+, S100+, EMA−) was crucial for the definitive diagnosis of benign myoepithelioma. A Ki67 index of 5–10% suggested a need for long-term surveillance. The postoperative course was uneventful with no recurrence at two years. This case highlights that myoepithelioma is a diagnostic chameleon and underscores the critical role of immunohistochemistry in achieving the correct diagnosis to guide appropriate management and follow-up.

Source: SAS Journal of Surgery

DOI: 10.36347/sasjs.2025.v11i10.009

Authors: A. Oussalem, A. Azgaoui, B. Dani, M. Boulaadas

Language: English

Topic: Salivary Gland Tumors Diagnosis and Treatment

Subfield: Surgery

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: diamond

OpenAlex ID: W4415001445

FWCI:

Cites:

Cited by:

Related to: