Diagnostic Dilemma in Parotid Tumors: A Case of Acinic Cell Carcinoma. A Case Report.

Background: Acinic cell carcinoma (ACC) of the parotid gland is a rare, low-grade malignancy that often masquerades as a benign tumor on both clinical and radiologic assessment, making early and accurate diagnosis challenging. We report the c Case Presentation: ase of a 26-year-old female who presented with a slowly enlarging, painless swelling below her right ear. Imaging via ultrasound and contrast-enhanced CT suggested a benign pleomorphic adenoma, while fine-needle aspiration cytology (FNAC) pointed toward an oncocytoma. Given these benign impressions, superficial parotidectomy was performed with facial nerve preservation. However, histopathological evaluation of the excised mass revealed classic features of acinic cell carcinoma, including serous acinar differentiation, zymogen granules, and microcystic spaces. The patient has remained disease-free on follow-up for over six months. This case highlights the diagnostic limitati Discussion: ons of FNAC and imaging in lowgrade parotid malignancies. ACC can mimic benign tumors both cytologically and radiographically, leading to misdiagnosis. Histopathology remains the gold standard for definitive diagnosis. Given the potential for late recurrences and metastasis-even in tumors that initially appear indolent-long-term clinical and radiologic surveillance is imperative. ACC of the parotid gland pose Conclusion: s a diagnostic dilemma due to its benign-like presentation. This case underscores the need for a high index of suspicion, especially in young patients, and the importance of comprehensive histopathological evaluation. A multidisciplinary approach remains critical to ensure optimal treatment and long-term outcomes.