Risk for colorectal adenomas among patients with pancreatic intraductal papillary mucinous neoplasms: a prospective case-control study

BACKGROUND AND AIMS: It has been reported that patients with intraductal papillary mucinous neoplasms of the pancreas are at an increased risk of colorectal cancer. The aim of our study was to investigate whether patients with intraductal papillary mucinous neoplasms are at a higher risk of colorectal adenomas with respect to the general population, as this condition represents the precursor of sporadic colorectal cancer. METHODS: A case-control study was conducted at the Catholic University and University Sapienza, Rome, Italy. The cases were patients with intraductal papillary mucinous neoplasms without history of colorectal cancer, who had underwent screening colonoscopy for the first time. The controls were individuals who had underwent first time colonoscopy for screening or evaluation of non-specific abdominal symptoms. Chi-square and Fisher tests were used to compare the distributions of categorical variables. RESULTS: We enrolled 122 cases and 246 controls. Colorectal polyps were found in 52 cases (42.6%) and 79 controls (32.1%) (p<0.05). In 29 cases (23.8%) and 57 controls (23.2%) histological examination disclosed adenomatous polyps (p=0.90). There was no difference between the groups in relation to the presence of polyps with low-grade (19.7% vs. 19.8%, p=0.98) and high-grade dysplasia (4.9% vs. 4.5%, p=0.85). CONCLUSION: Patients with intraductal papillary mucinous neoplasms of the pancreas are not at an increased risk for the development of adenomatous colorectal polyps.