Acinar cell carcinoma

It is a rare, aggressive malignancy, usually arising in adults, but it has been reported in children and adolescents as well.

Cytologic diagnostic features

• Groups of cells in nests, cords or acini
• Single cells
• Nuclear irregularity, crowding, overlapping
• Increased N/C ratio
• Conspicuous nucleoli
• Moderately abundant granular cytoplasm
• Absence of ductal epithelium

The granules are PAS positive and immunohistochemical stains for pancreatic enzymes (trypsin, lipase, chymotripsine, phospholipase A2), which are positive in acinar cells, helps to distinguish this tumor from other pancreatic tumors.