Which imaging modalities are recommended for the diagnosis of cholangiocarcinoma in primary care settings?

In primary care settings, the recommended imaging modality for the initial assessment of suspected cholangiocarcinoma is an urgent, direct access ultrasound scan. This is advised particularly when clinical features suggest biliary obstruction or an upper abdominal mass, as ultrasound is accessible and effective for detecting abnormalities in the biliary tree and liver ¹. If ultrasound findings are inconclusive or further characterization is needed, referral for advanced imaging such as contrast-enhanced computed tomography (CT) or magnetic resonance cholangiopancreatography (MRCP) is appropriate, typically in secondary care. MRCP is especially valuable for detailed visualization of the biliary ducts and can help differentiate cholangiocarcinoma from other causes of biliary obstruction (Grimsrud and Folseraas, 2019; Elias et al., 2024).

While primary care does not routinely perform CT or MRCP, these modalities are critical in the diagnostic pathway following initial ultrasound. CT scans, particularly pancreatic protocol CT, are used to assess the extent of disease and involvement of adjacent structures, aiding in staging and management planning ¹,². Endoscopic ultrasound (EUS) with guided tissue sampling is also a key diagnostic tool but is reserved for secondary care settings after initial imaging. Recent literature emphasizes the evolving role of MRCP and advanced imaging techniques in improving diagnostic accuracy and guiding biopsy decisions (Grimsrud and Folseraas, 2019; Elias et al., 2024).