Solid and cystic acinar cell tumour of the pancreas

Summary

The clinico-pathological features of five cases with a distinctive pancreatic tumour are presented. The tumours, which occurred only in young women and an adolescent girl, were of large size (2.5–10 cm), had an uncharacteristic symptomatology and showed fibrous encapsulation with no evidence of metastases. The histological features include (1) solid areas with a monomorphic cell pattern and intracellular PAS positive globules, and (2) large foci of degeneration with cystic necroses, haemorrhages and cholesterol granulomas. Some tumour cells were positive for α₁-antitrypsin. The ultrastructural demonstration of zymogen-like granules suggests an acinar origin for the tumours. We therefore propose the term solid and cystic acinar cell tumour. This tumour resembles the so called pancreatoblastomas in small children in some respects. It must be clearly distinguished, on the other hand, from acinar cell carcinoma with its acinic structures and poor prognosis. This lesion is not included in the WHO classification of pancreatic neoplasms.