Specifically pertaining to colorectal and pancreatic cancer alongside other gastrointestinal malignancies, I was wondering what the experience has been in terms of data dictionaries, statistical support, size of databases and completeness of data.
A good source for cancer database research, including gastrointestinal malignancies, is the The Surveillance, Epidemiology, and End Results (SEER) database. It is maintained by the National Cancer Institute.