DNA content measurements were performed by flow cytometry on eight ductal-type pancreatic adenocarcinomas. The majority of the neoplasms contained an aneuploid DNA content, with hyperdiploid DNA content being the most common abnormality. Two neoplasms had a diploid DNA content. These latter two patients are alive at 11 mo and 3 mo. The data suggest that a large percentage of pancreatic adenocarcinomas have an aneuploid DNA content. Further study is needed to evaluate the relationship between aneuploid DNA content and survival.