From the Guidelines
The lifetime risk of colon cancer in people with both Primary Sclerosing Cholangitis (PSC) and Inflammatory Bowel Disease (IBD) is significantly elevated, estimated to be between 25-30%. This risk is substantially higher than the general population risk of approximately 4-5% 1. Patients with this combination of conditions face a particularly high risk because PSC and IBD have synergistic effects on colorectal cancer development. The inflammation from IBD damages the colon lining, while the altered bile acid composition from PSC creates additional carcinogenic effects.
Some key points to consider:
- The risk begins earlier than in the general population and increases with longer disease duration 1.
- The presence of PSC further increases the risk 3-5-fold compared with that of IBD alone 1.
- Due to this elevated risk, patients with both PSC and IBD should undergo more intensive colorectal cancer surveillance with annual colonoscopies beginning at the time of PSC diagnosis, regardless of age or IBD duration.
- These colonoscopies should include multiple biopsies and chromoendoscopy (dye-spraying technique) to enhance detection of precancerous changes 1.
- The risk remains elevated even after liver transplantation for PSC, so continued surveillance is necessary throughout the patient's lifetime 1.
It is essential to note that the surveillance strategy should be tailored to the individual patient's risk factors, and the use of targeted biopsies using dye-based chromoendoscopy can increase the detection rate of precancerous changes 1. Overall, the management of patients with PSC and IBD requires a multidisciplinary approach, with close collaboration between gastroenterologists, hepatologists, and surgeons to optimize outcomes and reduce the risk of colorectal cancer.
From the Research
Lifetime Risk of Colon Cancer in People with PSC and IBD
The lifetime risk of colon cancer in people with Primary Sclerosing Cholangitis (PSC) and Inflammatory Bowel Disease (IBD) is a significant concern. Several studies have investigated this risk, providing valuable insights into the relationship between PSC, IBD, and colon cancer.
Key Findings
- A study published in 2011 found that patients with IBD and PSC have a high risk of developing colonic neoplasms soon after the coexistence of the two diseases is discovered, with an incidence rate of 21.5 per 100 patient years of follow-up 2.
- A 2024 study revealed that patients with PSC and concomitant IBD have a significantly heightened risk of colorectal cancer (CRC) compared to those with PSC-only, with 23.3% of PSC-IBD patients diagnosed with CRC 3.
- Another study published in 2008 noted that the presence of PSC is a risk factor for colon cancer in patients with IBD, and that the risk increases with longer duration of colitis, greater anatomic extent of colitis, and family history of CRC 4.
- A 2003 review article estimated that the risk of colon cancer for people with IBD increases by 0.5-1.0% yearly, 8-10 years after diagnosis, with the magnitude of CRC risk increasing with early age at IBD diagnosis, longer duration of symptoms, and extent of the disease 5.
Risk Factors and Screening
- The presence of PSC, family history of CRC, mucosal dysplasia, and DNA-aneuploidy are all risk factors for colon cancer in patients with IBD 4, 6.
- Regular colonoscopic surveillance with random biopsies is recommended to detect early mucosal dysplasia and reduce CRC mortality in IBD patients 4.
- The use of ursodeoxycholic acid (UDCA) may have a favorable impact on experimentally-induced CRC/neoplasia in rats, and may prevent further progression of manifest low-grade dysplasia in colorectal IBD 6.