Risk of metachronous colorectal cancer in patients with diverticular disease

In a large cohort of middle–older-aged adults who underwent colonoscopy, predominantly as outpatients, between 1995 and 2012, Troelsen et al. found a higher 3-year risk of proximally located post-colonoscopy colorectal cancer (PCCRC) in those with diverticulosis compared with those without diverticulosis [1]. Among patients who had colonoscopy, the all-cause mortality at 6 months was high, at 4.1%, despite most having low comorbidity. Female sex and proximal colon location were associated with PCCRC.

This study poses questions about patient selection for colonoscopy, as well as the quality of colonoscopy. Unfortunately, the article does not provide details of colonoscopists‘ experience, or of colonoscopy quality metrics such as rates of cecal intubation, polypectomy, bleeding, and perforation associated with the colonoscopies. The absence of data regarding the quality of bowel preparation, polyp types and location, and colorectal cancer (CRC) detection at the index colonoscopy does not permit determination of what proportion of CRCs would be deemed metachronous CRC.

Although synchronous biopsies and polypectomy performed during the same colonoscopy as diagnostic biopsies for CRC have been associated with metachronous CRC [2], there is a paucity of studies examining relationships between acute diverticulitis and metachronous CRC. The findings from the Troelsen et al. study highlight the importance of patient selection, timing, and complete and good quality colonoscopy in avoiding missed proximal lesions during technically difficult colonoscopies in older people with diverticulosis.

Publication History

Article published online:
27 September 2024

• References

• 1 Troelsen FS, Sørensen HT, Erichsen R. Risk of a post-colonoscopy colorectal cancer in patients with diverticular disease: a population-based cohort study. Endoscopy DOI: 10.1055/a-2264-8199. (PMID: 38331045)
• 2 Backes Y, Seerden TC, van Gestel RS. et al. Tumor seeding during colonoscopy as a possible cause for metachronous colorectal cancer. Gastroenterology 2019; 157: 1222-1232