Early cholangiocarcinoma detection with magnetic resonance imaging versus ultrasound in primary sclerosing cholangitis

BACKGROUND & AIMS Early detection of perihilar cholangiocarcinoma (CCA) among patients with primary sclerosing cholangitis (PSC) is important to identify more people eligible for curative therapy. While many recommend CCA screening, there are divergent opinions and limited data regarding the use of ultrasound or magnetic resonance imaging (MRI) for early CCA detection and it is unknown if there is benefit in testing asymptomatic individuals. Our aims were to assess the diagnostic performances and prognostic implications of ultrasound and MRI based CCA detection. APPROACH & RESULTS Multicenter review of 266 adults with PSC (CCA n=120) who underwent both an ultrasound and MRI within 3 months. Images were re-examined by radiologists who were blinded to the clinical information. Respectively, MRI had a higher area under the curve compared to ultrasound for CCA detection: 0.87 vs 0.70 entire cohort; 0.81 vs 0.59 asymptomatic; 0.88 vs 0.71 listed for CCA transplant protocol. The absence of symptoms at CCA diagnosis was associated with improved 5 year outcomes including overall survival (82% versus 46%, p <0.01) and recurrence free survival following liver transplant (89% versus 65%, p=0.04). Among those with asymptomatic CCA, MRI detection (compared to ultrasound) was associated with reduction in both mortality (hazard ratio [HR], 0.10; 95% CI, 0.01-0.96) and CCA progression after transplant listing (HR 0.10; 95%CI, 0.01-0.90). These benefits continued among patients who had annual monitoring and PSC for more than 1 year before CCA was diagnosed. CONCLUSIONS MRI is superior to ultrasound for the detection of early stage CCA in patients with PSC. Identification of CCA prior to the onset of symptoms with MRI is associated with improved outcomes.