Ductal adenocarcinoma of the head of the pancreas: incidence of tumor involvement beyond the Whipple resection line. Histological and immunocytochemical analysis of 37 total pancreatectomy specimens.

Intrapancreatic tumor spread of ductal adenocarcinoma of head of pancreas was examined histologically in 37 total pancreatectomy specimens. Five to 10 tissue blocks were prepared from grossly tumor-free tissue of each pancreas and coded by anatomic location. Step sections from each block were analyzed for carcinoma in situ lesions, invasive carcinoma, and benign ductal lesions. Immunocytochemical staining with monoclonal antibodies (MAb) against carcinoembryonic antigen (CEA) and nonspecific cross-reacting antigen 95 (NCA 95) were used to help in discriminating carcinoma in situ from papillary duct hyperplasia. In 3 of 37 pancreatectomy specimens (8%) tumor was found to spread in continuity from the primary carcinoma into the body and tail. In two of these three cases with tumor beyond the usual Whipple resection line, the tumor was present as a "carcinoma in situ" lesion along the main pancreatic duct. Since discontinuous tumor growth was not observed, multicentricity of duct type adenocarcinoma seems to occur less frequently than was previously reported.