1053 Primary Acinic Cell Carcinoma in a Young Female: A Case Report

Abstract

Abstract Background Acinic cell carcinoma (ACC) is a rare, low-grade tumour, accounting for about 5% of all primary salivary gland malignancies. ACCs predominate in the parotid gland, seen in the fifth and sixth decades of life and has a female predilection. Well-differentiated and low-grade tumours are associated with a favourable prognosis. Case Description We report a case of a 16-year-old female, presenting with a right parotid lump, slowly increasing over the last year. Clinical examination revealed a 1.5cm right parotid nodule with no facial nerve involvement and presence of cervical lymphadenopathy. Past medical history was unremarkable. Findings Radiological investigations revealed a well-circumscribed lobulated lesion in the anterior right parotid gland with presence of reactive lymph nodes bilaterally. Differential diagnoses included Warthin's tumour, which would have been unusual in this age group, and the patient underwent a right partial parotidectomy. Histological examination showed a multinodular appearance with some marked granular cytoplasm with oncolytic and lymphoid infiltrate. Immunohistochemistry was negative for S100, positive with DOG-1. There were widespread PAS-D-resistant granules throughout the tumour cells, with ki67 proliferation index of approximately 5%. Results The tumour was completely excised, and the patient made a full recovery and considered to have a good long-term prognosis. Conclusion This is an unusual case of ACC seen in this age group and gender, where less than 4% of cases of ACC have been reported in patients younger than 20. It is important to consider differential diagnoses of salivary gland pathology, such as ACC in the young female patient.