Pseudopolyps Do Not Predict Colorectal Cancer Risk in IBD Patients, 20-year Retrospective Study Shows

Pseudopolyps — large protrusions of the intestinal layer formed in the regenerative and healing phases of damaged tissue — are not predictors of risk for developing colorectal cancer among patients with inflammatory bowel diseases (IBD), a 20-year retrospective study reports. 

The study “No Association Between Pseudopolyps and Colorectal Neoplasia in Patients With Inflammatory Bowel Diseases” was published in the journal Gastroenterology.

Patients with IBD are at an increased risk for developing colorectal cancer, especially those positive for post-inflammatory polyps (also called pseudopolyps), according to previous research. These studies showed that post-inflammatory polyps were found in 20 to 45 percent of IBD patients and that their presence increased the risk of developing colorectal cancer by 1.9 to 2.5 times.

Current European guidelines propose that patients with several risk factors, including post-inflammatory polyps, should be monitored with frequent colonoscopies.

However, a large retrospective study on patients with ulcerative colitis, who were being monitored for early signs of colorectal cancer, reported no increased risk for patients with post-inflammatory polyps to develop the disease or for the polyps’ progression into more advanced stages. Further studies are warranted to know whether these polyps can act as independent predictors of colorectal cancer.

Therefore, researchers at the Icahn School of Medicine at Mount Sinai in New York City, along with colleagues at the University Medical Center Utrecht in the Netherlands, conducted a multicenter retrospective study on 1,582 IBD patients with a long-term history of IBD (eight years or more), and no prior history of colorectal cancer or surgery to remove part of the colon (called a colectomy).

Patients were monitored for 20 years, from January 1997 to January 2017. They were recruited among five academic hospitals and two large non-academic hospitals in the U.S. and the Netherlands.

In total, 462 patients (29.2%) were positive for post-inflammatory polyps, which were associated with more severe inflammation and extensive disease. However, patients were less likely to develop primary sclerosing cholangitis, chronic liver, and gallbladder disease characterized by inflammation of the bile ducts.

During followup, 17 patients (3.7%) with post-inflammatory polyps and 24 (2%) of those without polyps developed advanced colorectal cancer. This showed that the presence of post-inflammatory polyps did not independently increase the risk for the disease.

Patients with post-inflammatory polyps underwent more colectomies than those without them, but the surgery was likely a strategy for hard-to-treat IBD disease, and not because they had developed signs of colorectal cancer.

This “is very good news for the IBD patient with pseudopolyps, as their surveillance colonoscopies will likely be affected by these results,” Steven Itzkowitz, MD, professor of medicine and oncology at the Icahn School of Medicine, and one of the study’s lead authors, said in a press release.

“We hope that doctors treating these IBD patients would be less fearful of colon cancer risk in a colon with PIPs (post-inflammatory polyps), and forego shortened intervals of surveillance as a result of our findings, lending to improved quality of life and lower healthcare costs,” he added.