Pseudopolyps not associated with greater colorectal cancer risk

Last Updated: 2018-12-18

By Reuters Staff

NEW YORK (Reuters Health) - Post-inflammatory polyps (PIPs) are not associated with colorectal neoplasia (CRN) in patients with inflammatory bowel disease (IBD), according to new findings.

However, inflammation of the colon was more severe in patients with PIPs, who were also more likely to undergo colectomy.

"Intervals for surveillance should not be shortened solely based on the presence of PIPs," Dr. Steven H. Itzkowitz of Mount Sinai Hospital in New York City and colleagues conclude in Gastroenterology, online December 7.

Up to 45% of IBD patients have PIPs, also known as pseudopolyps. While European guidelines state that PIPs are a risk factor for colorectal cancer (CRC) in IBD patients, the authors add, evidence on the association has been mixed.

"Theoretically, the risk of CRN could be increased in patients with PIPs if their presence indicates prior severe inflammation. Alternatively, PIPs may obscure otherwise visible and resectable dysplastic lesions during surveillance," they write. "Direct malignant transformation of PIPs is generally considered unlikely. Regardless of the mechanism, there is a gap in the literature as to whether PIPs are independent predictors of ACRN."

To investigate, the team looked at 1,582 IBD patients from two large cohorts who underwent colonosopic surveillance in 1997-2017 at Mount Sinai or Utrecht University Medical Center, in the Netherlands; 462 patients (29.2%) had PIPs.

Patients with pseudopolyps had significant more severe inflammation (adjusted odds ratio, 1.32), greater disease extent (aOR, 1.92) and a lower risk of primary sclerosing cholangitis (aOR, 0.38).

Time to developing advanced CRN over a median follow-up of 4.8 years was similar for the patients with and without PIPs.

During follow-up, 8.4% of patients with PIPs underwent colectomy, versus 3.9% of patients without PIPs. Time to colectomy was also shorter for patients with PIPs.

"Our findings should provide some degree of reassurance for clinicians and patients that PIPs are not, in themselves, the worrisome lesions they once were considered. Our data suggest that PIPs are not independently associated with increased risk of any degree of CRN on intermediate-term follow-up, an observation that should be considered in developing future IBD colonoscopic surveillance guidelines," the authors conclude.

Dr. Itzkowitz was not available for an interview by press time.

SOURCE: https://bit.ly/2rEyKeO

Gastroenterology 2018.