Establishment of a novel model of peritoneal carcinomatosis of the peritoneal extension type.

AIM

Patients with scirrhous carcinoma of the gastrointestinal tract frequently develop peritoneal carcinomatosis-particularly of the peritoneal extension type (PET), which has a bad prognosis. We developed a novel animal model, suitable for testing treatments for PET.

MATERIAL AND METHODS

In order to develop the model, we scraped the entire peritoneum of Fischer 344 rats with sterile cotton swabs and injected 1 × 10(6) cells of the RCN-9 cell type into the peritoneal cavity.

RESULTS

In the novel experimental model, RCN-9 cells adhered only to the exposed basement membrane. The submesothelial layer and fibroblasts in the submesothelial layer grew and increased to a maximum at day 7, then decreased during late-phase peritoneal carcinomatosis. At day 14, RCN-9 cells coated the peritoneum in a manner similar to PET.

CONCLUSION

We successfully established a novel animal model of peritoneal carcinomatosis that mimics clinicopathological features of PET. Fibroblasts in the submesothelial layer potentially play an important role in peritoneal carcinomatosis.