The type of inflammation a patient with inflammatory bowel disease such as crohn’s or colitis has may be the key to determining whether they are likely to develop colorectal cancer, according to a new London-based study.
Researchers at Lawson Health Research Institute and Western University Schulich School of Medicine & Dentistry examined six different types of colitis in a new preclinical study. Each of the six results in different forms of inflammation, researchers said.
“We found it wasn’t necessarily the severity and duration of the inflammation that was most important, but rather the type of inflammation,” said Dr. Samuel Asfaha, a Lawson Scientist and Gastroenterologist at London Health Sciences Centre.
Preclinical models showed only one type of colitis led to cancer. It had a newly identified subset of immune cells called macrophages that were critical to the development of the disease. With that knowledge, researchers determined they could prevent colitis-associated cancer if they blocked these specific immune cells.
“To our knowledge this is the first published study that extensively compares the different models of colitis or inflammation in the colon,” Lead Author and Schulich PhD Student Dr. Alice Shin said. “We are also the first to show that this specialized subset of macrophages that we identified are important for the initiation phase of inflammation-associated cancer.”
Further study will be needed to determine how the macrophages initiate cancer and whether a biomarker could be found to identify which patients are at higher risk of developing cancer. Annual cancer screening of patients with chronic inflammatory bowel disease could aid in this.
“By being able to differentiate those who are most at risk for developing cancer versus those who are at lower risk, we can focus our attention on those who are at increased risk,” said Asfaha, who is also an associate professor at Schulich.
Researchers are optimistic continued study could also point to more effective treatments for colitis-associated cancer.
The results of the study have been published in the medical journal Gastroenterology.