Celiac.com 02/28/2011 - Celiac disease is associated with an increased risk of lymphoma and small bowel malignancy. Colorectal cancer is the most common gastrointestinal cancers in the United States, but most studies have not found no higher rates of colorectal cancer for people with celiac disease, compared with rates in the general population.
The results of these studies might in fact be describing a true null relationship between celiac disease and colorectal cancers. However, the results may also be influenced by better health-care among patients with known celiac disease, particularly among those with gastroenterologists who are likely to perform screening colonoscopy.
The team of researchers sought to assess the underlying risk of colorectal cancer in patients with celiac disease by quantifying the relative prevalence of precancerous colorectal adenomas in these patients compared with patients without celiac disease in a cohort of individuals undergoing colonoscopy. The team included B. Lebwohl; E. Stavsky; A. I. Neugut; and P. H. R. Green.
To isolate the association of celiac disease with colorectal adenomas, the team controlled for three important predictors of adenoma detection on colonoscopy: endoscopist, patient age and patient gender.
They then identified all celiac disease patients who underwent colonoscopy at their institution during a 44-month period. They matched each celiac disease patient by age, gender and endoscopist, with non-celiac control subject.
The team then compared the adenoma rates between these groups, and used multivariate analysis to assess the independent association of celiac disease with adenomas.
The team isolated 180 patients with celiac disease and 346 control subjects. A total of 13% of celiac disease patients and 17% of controls (P = 0.20) showed at least one adenoma.
Multivariate analysis showed that age (OR per year 1.04, 95% CI 1.02–1.07) and male gender (OR 2.33, 95% CI 1.36–3.98) were both associated with higher rates of adenoma.
However, there were no higher adenoma rates among people with celiac disease (OR 0.75, 95% CI 0.41–1.34).
The study provides strong support for the notion that celiac disease is not associated with higher rates of colorectal cancer.
They conclude that the lack of increased rates of colorectal cancer is related to a true average risk of colorectal neoplasia, rather than reflecting higher colonoscopy and associated polyp removals among people with celiac disease.