Classification of pancreatic cancer (nonendocrine).

From the records of 757 patients listed as having had pancreatic cancer at Memorial Hospital during the years 1949 through 1972, adequate clinical data and pathologic tissue were available for study in 508 patients. Review of these cases led to a histologic classification into 11 subcategories and one unclassified group. The most common type was the duct cell adenocarcinoma (75%), and the remaining subgroups each made up less than 5% of the total. All except one of the subtypes were well-known carcinoma patterns that occur in other organs. A small-gland carcinoma, the microadenocarcinoma, has not usually been associated with the pancreas. Some types were associated with short survival periods of a few months after diagnosis--for example, duct cell, giant cell, acinar cell, and adenosquamous carcinomas and microadenocarcinoma. Patients with mucinous carcinoma had a mean survival period of a few months longer, and the few patients with mucinous cystadenocarcinoma had a much longer median survival. Two rare types--papillary cystic tumor and pancreaticoblastoma--are mentioned and illustrated. It is hoped that one or more of these types can be associated with an etiologic agent, some clinical feature, or responsiveness to a therapeutic regimen.