IBD increases the risk of colorectal cancer. People with IBD are therefore offered surveillance by colonoscopy in order to detect a precursor to colorectal cancer called dysplasia. However, sometimes dysplastic lesions are difficult to spot by colonoscopy, can be confused with other types of lesions and are not consistently graded by different pathologists. Patients are also undergoing frequent, invasive colonoscopies without these being tailored to their risk of getting cancer.
In order to better predict colorectal cancer risk in people with IBD, a team of pathologists based in the USA, New Zealand and Australia led by Won-Tak Choi investigated the association between cancer risk and the histology of dysplastic lesions. They also came up with a set of criteria to better grade dysplastic sub-types.
A team of 6 experienced pathologists led by Nadia Nasreddin and Simon Leedham (Centre for Human Genetics) set out to validate these findings using 243 regions from 129 lesions from 89 patients with IBD. As observed previously, there was common disagreement between the grading of dysplasia between pathologists. However, the Oxford-led team were unable to validate the published association between dysplasia subtype and cancer risk, in part due to the complexity of the criteria for grading dysplastic sub-types.
This study, published in the journal Modern Pathology, therefore highlights the need for other measures, such as molecular biomarkers, by which to stratify risk of cancer in people with IBD.