The first Australian study of primary sclerosing cholangitis (PSC) has confirmed a high rate of gastrointestinal malignancy especially in patients who also have inflammatory bowel disease (IBD).

The retrospective study of 208 patients from two tertiary referral hospitals in Sydney found 22% of patients with both PSC and IBD developed cancers including cholangiocarcinoma, colorectal adenocarcinoma and hepatocellular carcinoma.

About 2% of patients with PSC alone developed gastrointestinal cancers during the 20-year study period.

Lead researcher Professor Rupert Leong, head of the IBD service at Concord Hospital, said cancer was the most common cause of death in the cohort.

“This is a rare but terrible disease with a poor prognosis. Even with adequate colonoscopy surveillance for colorectal cancers and even after colectomy, we can’t avoid the liver and bile duct cancers that occur in this group,” he told the limbic.

While the study found the combined outcome of death or liver transplant was more common in patients with both PSC and IBD, there was no significant difference in rates of liver transplant or length of transplant-free survival between those with or without IBD.

Professor Leong said only an elevated International Normalised Ratio (INR) was found to be significantly associated with an increased risk of death or liver transplantation.

“We were looking for a biomarker for poor prognosis and INR is not surprising given it is an important factor in both the Child-Pugh and MELD scores for liver disease,” he said.

“The finding certainly highlights the need for regular INR monitoring in the context of liver-focused supportive care for these patients.”

The study found 82% of patients were prescribed ursodeoxycholic acid, which Professor Leong said helped improve liver function tests but didn’t translate to a survival benefit.

“The frightening aspect of this disease is there are essentially no drugs available. Medical management is essentially supportive care – off label UDCA, naltrexone and some antibiotics – and liver transplant as required.”