Acinic Cell Carcinoma of Parotid Gland: Report of Three Cases and Literature Review

Primary Acinic Cell Carcinoma (ACC) is an uncommon salivary gland (SG) tumor, making up 1% of all SG neoplasms. The parotid is the most common topography, and the ACCs are more frequently diagnosed in the fourth to sixth decades of life. In this study, along with a brief review of the literature, we discussed the clinical, histopathological, and prognostic features of these SG tumors through three reported cases. All of the tumors occurred in left parotid of non-smoking and non-drinking white patients, aging 80, 51, and 56 years. The lesions were painless and presented as slow-growing, large, firm, and movable solitary masses in the left mandible angle. The patients were initially submitted to a clinical, radiographic and computed tomography exam, followed by fine-needle aspiration and an excisional biopsy to confirm the diagnosis. All of the patients were treated with surgery followed by radiotherapy. Two of the patients had a local recurrence, one of which had cervical lymph node involvement, but both are still alive. The other patient did not have a local recurrence or lymph node involvement, but developed distant pulmonary metastases and died. The follow-up times were 18, 102 e 22 (with death) months. Upon histopathological analysis, ACC typically shows a solid pattern of growth, with cells exhibiting serous acinar cell differentiation and cytoplasmic basophilic granules. Complete surgical resection is the usual therapeutic choice. The literature describes ACC as a tumor with low malignant potential, but several recurrences and metastasis have been reported, as verified in the present study