The purpose of this study was to describe the inoculation technique and patterns of growth as well as to characterize typical histological features of Lewis rat subcutaneous and intrapancreatic
tumors, induced by inoculation of cultured
pancreatic cancer cells (DSL-6A/C1). Subcutaneous inoculation of cultured cells produced a solid
tumor that was a locally invasive, well- to moderately differentiated ductal
adenocarcinoma.
Tumor take was 100% in animals 5 weeks of age;
tumor growth was consistent and predictable and a
tumor volume of approximately 1 cm3 was reached in 8 weeks. After intrapancreatic
transplantation the
tumors showed the same histological features as subcutaneous
tumors. During inoculation
carcinoma cells easily spread around the injected area, and after 2 weeks both pancreatic
tumors and superficially infiltrating
carcinomas were found in the liver and spleen and around the peritoneum.
Tumor take was 60% and
tumor growth was somewhat indefinite and unpredictable in the pancreas. However, by reducing the injected
carcinoma cell volume and solving the technical problems, 100%
tumor take was achieved. The
tumor volume reached 2 mm3 during 2 weeks and larger
tumors showed a tendency for invasion. According to our results, subcutaneous as well as intrapancreatic
tumor induction with cultured cells offers a model for
pancreatic cancer studies.