Mucoepidermoid carcinoma - A common neoplasm at an unusual site, mimicking a benign cyst on cytology

Abstract

Mucoepidermoid carcinoma (MEC) is known to be a relatively common neoplasm of the major and minor salivary glands that can secondarily involve skin. The clinical manifestations, diagnostic cytology and histopathology of MEC presenting as a clinically benign periauricular cystic nodule have been analyzed. The challenge of accurate diagnosis can be illustrated by the fact that initially, on cytology, this tumor was misdiagnosed as a benign epidermal inclusion cyst due to the presence of mucin-filled cells which were misinterpreted as cyst macrophages. This case report emphasizes the need to include parotid tumors in the differential diagnosis of all periauricular cyst-like expansions. We also briefly discuss the reasons for false-positive cytology in this case. Delay in accurate diagnosis may result in larger surgical procedures, such as radical neck dissection, that may otherwise be avoided.

Unraveling an Unusual Presentation of Parotid Malignancy: A Case Report

“…In our case, the patient presented with post-auricular swelling, which was initially misdiagnosed as a benign lymph node. An isolated post-auricular swelling is a rare presentation of MEC [ 7 ]. A similar case study discussed a benign-looking postauricular lesion that was misdiagnosed as an epidermal inclusion cyst, which, on further histological examination, was suggestive of MEC [ 7 ].…”