Crystalloid Granuloma of Parotid Gland: A Case Report With Review of the Literature

Crystalloid granuloma (CG) of salivary gland is an extremely rare inflammatory disease, and only 6 cases have been reported in the English literature. CG is histologically characterized by a granulomatous reaction to amylase crystalloid deposition. A 73-year-old woman presented with a painful left neck mass. Computed tomography depicted a mass located in the lower pole of the left parotid gland, suspicious for a tumoral lesion. Preoperative fine needle aspiration cytology found amylase crystalloid deposition with a few inflammatory cells. Surgical sections of the mass revealed formation of a granuloma containing abundant eosinophilic but glassy and transparent amorphous crystalloids, suggestive of α-amylase crystalloid. No neoplastic elements were detected. The case was eventually diagnosed with CG in the parotid gland. Our findings suggest that when we identify amylase crystalloids in fine needle aspiration cytology smears from the salivary gland, CG should be considered even if neoplasm is clinically or radiographically suspected