recommending annual surveillance with a specialized imaging study and serum markers, although consensus regarding the modality and interval has yet to be established. Similarly, a screening colonoscopy is recommended in people who receive a new diagnosis of primary sclerosing cholangitis since their risk of colorectal cancer is 10 times higher than that of the general population. PSC is strongly associated with IBD, in particular ulcerative colitis (UC) and to a lesser extent Crohn's disease. As many as 5% of patients with IBD are co-diagnosed with PSC, and approximately 70% of people with PSC have IBD. Of note, the presence of colitis appears to be associated with a greater risk of liver disease progression and bile duct cancer (cholangiocarcinoma) development, although this relationship remains poorly understood. Close monitoring of PSC patients is vital. Various forms of gallbladder disease such as gallstones and gallbladder polyps are also common in those with PSC. Approximately 25% of people with PSC have gallstones. Ultrasound surveillance of the gallbladder every year is recommended for people with PSC. Any person with PSC who is found to have a mass in the gallbladder should undergo surgical removal of the gallbladder due to the high risk of cholangiocarcinoma. Osteoporosis (hepatic osteodystrophy) and hypothyroidism are also associated with PSC. A 2–3:1 male-to-female predilection occurs in primary sclerosing cholangitis. PSC can affect men and women at any age, although it is commonly diagnosed in the fourth decade of life, most often in the presence of IBD. PSC progresses slowly and is often asymptomatic, so it can be present for years before it is diagnosed and before it causes clinically significant consequences. Relatively few data are available on the prevalence and incidence of PSC, with studies in different countries showing annual incidence of 0.068–1.3 per 100,000 people and prevalence 0.22–8.5 per 100,000; given that PSC is closely linked with ulcerative colitis, the risk is likely higher in populations where UC is more common. In the United States, an estimated 29,000 individuals have PSC. Research Although no curative treatment is known, several clinical trials are underway that aim to slow progression of this liver disease. Obeticholic acid is being investigated as a possible treatment for PSC due to its antifibrotic effects. Simtuzumab is a monoclonal antibody against the profibrotic enzyme LOXL2 that is being developed as a possible therapy for PSC. Notable cases Chris Klug – professional snowboarder with PSC who had liver