Background: For all the interest in the natural history of colorectal cancer (CRC) in ulcerative colitis (UC) and Crohn's disease (CD), surprisingly few data have been published regarding CRC in indeterminate colitis (IC). We present our experience with 15 cases of IC-associated CRC in order to assess their clinicopathological features and to determine their survival rates.
Methods: We retrospectively reviewed the medical records of patients with IC admitted to the Mount Sinai Hospital between 1994 and 2007 and who developed CRC. All patients were operated on and follow-up was complete for all patients to the closing date of study or to the time of death.
Results: A total of 19 adenocarcinomas were present in this series. There were 3 patients with multiple cancers; all cancers occurred in segments of colitis. The mean age at onset of IC was 28 years and the average time progression from the IC diagnosis to CRC was 19 years. Dysplasia was detected in 10 of the cases; 3 patients had mucinous tumors. Five patients had stage I tumors; 5 stage II; 4 stage III; 1 stage IV. There were 4 deaths due to CRC. The overall 5-year survival was 42%.
Conclusions: CRC in IC shares most of the clinical and pathologic features as well as survival outcomes with CRC that occurs in the most prevalent forms of inflammatory bowel disease (IBD), UC and CD. Surveillance regimens currently used in the other forms of IBD seem applicable to IC patients as well.