Acinic Cell Carcinoma of the Parotid Initially Misdiagnosed as Pleomorphic Adenoma on FNAC: A Case Report

Abstract

Acinic cell carcinoma (ACC) is a rare malignant salivary gland tumour that can closely resemble benign lesions on clinical examination and FNA. A 27-year-old woman presented with a small, tender, mobile parotid mass that was
initially diagnosed as pleomorphic adenoma on FNA. She underwent extracapsular excision, but postoperative histopathology revealed ACC, confirmed by GCDFP-15 positivity and absence of myoepithelial cells (p63-
negative). This case underscores how ACC can mimic benign parotid tumours and highlights the importance of histopathology and immunohistochemistry for definitive diagnosis.