Assessing Morphological Diversity of Acinic Cell Carcinoma of Salivary Glands at a Tertiary Care Hospital in Pakistan.

Introduction: Acinic cell carcinoma (AciCC) is a rare clinical entity and a salivary gland malignancy. It is associated with wide histological variations in the cytomorphological patterns.

Methods: Sixty cases diagnosed as AciCC from 2002 to 2023 were assessed for diverse cytomorphological patterns.

Results: The mean age of patients at the time of diagnosis was 44.35±16.8 years ranging from 15 to 81 years. Females comprised 58.3% for a F: M ratio of 1.4:1. Fifty three cases (88.3%) occurred in the parotid gland, two cases in the nasal region (3.3%), and one case each in the soft plate and upper lip (1.7%). The location of the remaining three cases was not specified. The most common presenting complaint was a well-defined facial swelling associated with pain. The average tumor size was 3.8±1.9 cm. The most predominant architectural pattern was solid (83.3%) followed by microcystic (60%), then follicular (41.7%), papillary cystic (14.3%), and tubulocystic (28.6%), and AciCC with de-differentiation/high-grade transformation was reported in three cases (5%). In 83.3% of the cases (50 out of 60), we noticed a mixture of two or more growth patterns. Other degenerative changes included prominent lymphoid stroma, hemorrhage, and cystic change.

Conclusion: Awareness and recognition of diverse cytomorphological patterns of AciCC, especially in institutions of a developing country where there is limited availability of highly specific and sensitive immunohistochemical stains or molecular diagnostics, are crucial and essential.