Development of experimental cancer in the head of the pancreas by surgical induction of tissue injury.

The majority of carcinomas of the pancreas in humans are of ductal origin and are located in the head of the gland. These clinical characteristics however, are not affected in traditional animal models of the disease. Partial pancreatic duct obstruction with ductal epithelial hyperplasia was produced in the Syrian golden hamster by wrapping the head of the pancreas with cellophane tape. Wrapped and unwrapped animals were then exposed to an exogenous carcinogen (N-nitrosobis[2-oxopropyl]amine). Assay of serum ribonuclease activity was used as a marker of disease. Invasive lesions developed in both groups of animals. Fifty percent of the tumors in the Group II (cellophane wrap and N-nitrosobis [2-oxopropyl] amine) hamsters were located in the head of the gland and were of ductal origin. All tumors in animals receiving N-nitrosobis [2-oxopropyl]amine alone (Group I) occurred peripherally and were derived from ductular or acinar tissue. Elevation of serum ribonuclease activity was noted early in the course of carcinogenesis, thereafter returning to normal, which may explain the clinical controversy regarding this marker. This new model should enhance our knowledge of the interrelationships between etiologic factors, precursor lesions, and pancreatic cancer.