Exocrine pancreatic tumours and their histological classification. A study based on 167 autopsy and 97 surgical cases.

Based on histopathological examination of 264 exocrine pancreatic tumours (167 autopsy and 97 surgical) from the files of the Institute of Pathology, University of Hamburg, over a 15-yr period (1966-1980), a histogenetic classification is proposed. In addition to the more common neoplasms this also includes rarer and more recently defined entities. Of the 264 tumours, 250 were of duct origin, 10 acinar and four of uncertain histogenesis. Ductal adenocarcinoma, subdivided into a well-differentiated and a poorly-differentiated type, was most frequent (81.1%), followed by its variants: pleomorphic giant cell carcinoma 5.3%, adenosquamous carcinoma 3.8%, and mucinous carcinoma 1.1%. All these had a poor prognosis. Serous cystadenoma (1.1%), mucinous cystic tumour (1.5%) and intraductal papilloma (0.8%), which were rare tumours and mostly apparent in surgical material, proved to be benign or of only latent malignancy. The group of tumours of acinar cell origin consisted of the solid and cystic tumour (2.7%) with favourable prognosis and the acinar cell carcinoma (1.1%). No pancreatoblastoma was observed. The pleomorphic carcinomas of the small cell type (1.5%) were classed as tumours of uncertain histogenesis.