Although restorative proctocolectomy with ileal pouch–anal anastomosis (IPAA) substantially reduces the risk of colorectal cancer in patients with inflammatory bowel disease (IBD), subsequent pouch neoplasia can develop.
There are few data on the incidence of and risk factors for neoplasia, so there is no consensus on the need for pouch surveillance.
Dr Lauranne Derikx and colleagues determined the cumulative incidence of pouch neoplasia in patients with IBD and identify risk factors for developing pouch neoplasia.
The research team searched the Dutch Pathology Registry (PALGA) to identify all patients with IBD and IPAA in The Netherlands from 1991 to 2012.
|Respective cumulative incidences at 5 years was 1%|
The team calculated the cumulative incidence of pouch neoplasia and performed a case-control study to identify risk factors.
Demographic and clinical variables were analyzed with univariable and multivariable Cox regression analyses.
The researchers identified 1200 patients with IBD and ileal pouch–anal anastomosis, of which 25 developed pouch neoplasia, including 16 adenocarcinomas.
Respective cumulative incidences at 5, 10, 15, and 20 years were 1.0%, 2.0%, 3.7%, and 6.9% for pouch neoplasia, and 0.6%, 1.4%, 2.1%, and 3.3% for pouch carcinoma.
The team observed that a history of colorectal neoplasia was the only risk factor associated with pouch neoplasia.
The research team noted that hazard ratios were 3.8 for prior dysplasia, and 24.7 for prior carcinoma.
Dr Derikx's team concludes, "The incidence of pouch neoplasia in patients with IBD without a history of colorectal neoplasia is relatively low."
"Prior dysplasia or colon cancer is associated with an approximate 4- and 25-fold increase in risk, respectively, of developing pouch neoplasia."