Risks and use of ERCP during the diagnostic workup in a national cohort of biliary cancer

In biliary cancer, the indication of endoscopic intervention might be diagnostic as well as therapeutic, in the latter situation with the aim to relieve biliary obstruction e.g. by stenting. Our aim was to investigate the use of endoscopic biliary interventions during the diagnostic workup of biliary cancers in a national cohort, and to evaluate their complications, especially cholangitis and pancreatitis.

This is a registry-based study of national cohort of patients with biliary cancers in Sweden 2010-2020. The use of endoscopic retrograde cholangiopancreatography (ERCP) during the diagnostic work up period before treatment onset, and risk of complications were evaluated in patients with gallbladder cancer, intrahepatic-, perihilar- and distal cholangiocarcinoma. The risk of complications was compared depending on age, sex, comorbidity, in relation to stage and curative intent, endoscopy unit size, and with relation to survival.

Forty percent of the patients with biliary cancer underwent ERCP during the diagnostic workup, with variations depending on diagnosis. There was a 20% overall risk of periprocedural complications, a 9% risk of post-ERCP-pancreatitis (PEP), and a 6% risk of cholangitis. Increasing tumor stage did not increase risk, nor did comorbidity. The complication rates were slightly higher for younger patients and those undergoing curative treatment. For perihilar cholangiocarcinoma (pCCA) treated with curative intention, the risk of periprocedural complications was as high as 30.7%. No association between post-ERCP complications and survival was found.

Irrespective of type of biliary cancer, ERCP is frequently used during diagnostic workup. The complication risk indicates that primary biliary cancers are complication prone, regardless of stage. Notably the risk of complications was the highest for younger patients with low comorbidity scores, as well as for patients undergoing curatively aiming treatment.