Immunocytochemical markers of uncommon pancreatic tumors. Acinar cell carcinoma, pancreatoblastoma, and solid cystic (papillary‐cystic) tumor

Nine acinar cell carcinomas of the pancreas, 2 pancreatoblastomas, 16 solid‐cystic (papillary‐cystic) tumors, and 20 ductal adenocarcinomas were immunocytochemically investigated using antisera against four pancreatic enzymes (alpha‐amylase, lipase, trypsinogen, chymotrypsinogen), four pancreatic hormones, neuron specific enolase (NSE), alpha‐1‐antitrypsin (AAT), carcinoembryonic antigen (CEA), and CA 19–9. Lipase, trypsinogen, and chymotrypsinogen, but no alpha‐amylase were detected in all acinar cell carcinomas and pancreatoblastomas. In contrast, solid‐cystic tumors (SCT) were negative for pancreatic enzymes but 2 of 16 stained with NSE. No neuroendocrine granules or pancreatic hormones could be demonstrated. AAT was found in all tumors except ductal adenocarcinomas, which stained with CEA and CA 19–9. The study established pancreatic enzymes (except alpha‐amylase) as immunocytochemical markers for acinar cell carcinomas and pancreatoblastomas. There is as yet no marker specific for SCT, which would elucidate the obscure histogenetic origin and phenotypic differentiation of these tumors. Cancer 59:729‐747, 1987.