Ulcerative Colitis Associated with Increased Risk of Colorectal Cancer

Patients with ulcerative colitis (UC) have an increased risk of developing colorectal cancer (CRC), are diagnosed with less advanced CRC, and are at increased risk of death from CRC, compared with those without UC, according to a recent study.

Furthermore, CRC surveillance should likely be focused on patients diagnosed with Crohn disease before 40 years of age, on patients with colon inflammation, and on those who have primary sclerosing cholangitis (PSC).

Investigators at the Karolinska Instituet in Stockholm, Sweden, aimed to compare both overall and country-specific risks of CRC mortality and incident CRC among patients with UC. In a population-based cohort study of 96,447 patients with UC (32,919 in Denmark and 63,528 in Sweden), patients were given a follow-up for CRC incidence and mortality between January 1969 and December 2017 and compared with a matched reference of 949,207 individuals from the general population.

Patients with UC were selected from national registers and included in the analysis if they had 2 or more records with a relevant International Classification of Disease in the patient register or 1 record plus a colorectal biopsy report with a morphology code suggestive of inflammatory bowel disease.

For every patient with UC, the study team selected matched reference individuals from the total population registers of Denmark and Sweden, who were matched for sex, age, birth year, and place of residence.

During follow-up, the researchers observed 1336 incident CRCs in the UC cohort and 9544 incident CRCs in reference individuals. In the UC cohort, 639 patients died from CRC compared with 4451 reference individuals during the same period.

The CRC stage distribution in patients with UC was less advanced than in matched reference individuals, but taking tumor stage into account, patients with UC and CRC remained at increased risk of CRC death.

The authors concluded that there is need for improvement in international surveillance guidelines.

Reference

• Colorectal Cancer in Ulcerative Colitis and Crohn’s Disease [news release]. ESMO website. Published February 17, 2020. https://www.esmo.org/oncology-news/colorectal-cancer-in-ulcerative-colitis-and-crohn-s-disease. Accessed February 20, 2020.