Circulating Tumor DNA Guided vs Opportunistic Colonoscopy Screening for CRC Detection After Acute Colonic Diverticulitis - the Diverticulitis Study

Acute colonic diverticulitis is when a part of the colon gets swollen and inflamed. The diagnosis is based on a CT scan, which can show thickening of the colonic walls and infiltration of the diverticula. These changes and the concomitant symptoms can overlap with colorectal cancer (CRC). Therefore, the guidelines suggest that people with diverticulitis should be offered a colonoscopy to ensure, that CRC is not the underlying cause of the changes and symptoms.

In Denmark, a lot of people get hospitalized each year due to diverticulitis, and many of them end up having colonoscopies with the purpose of excluding CRC. Currently, there are no methods for guiding colonoscopies following a diverticulitis episode, resulting in numerous unnecessary colonoscopies each year.

In the Diverticulitis study, we want to investigate if a simple blood test analyzed for the presence of circulating tumor DNA (ctDNA), can help us decide who needs a colonoscopy. We will collect blood samples from 220 people with diverticulitis and categorize them into ctDNA positive and negative groups. The ctDNA category will be compared to the colonoscopy results to see if there is a correlation between being ctDNA positive and having a CRC diagnosed at the colonoscopy.

This study could change clinical practice since we anticipate that ctDNA-guided triaging of diverticulitis patients is a cost-effective strategy for selecting diverticulitis patients needing colonoscopy, ensuring detection of the underlying CRC, and significantly reducing the number of patients undergoing unnecessary colonoscopy.