Hilar cholangiocarcinomas: T2-weighted spin-echo and gadolinium-enhanced FLASH MR imaging

PURPOSE: To investigate the use of magnetic resonance (MR) imaging with dynamic gadopentetate dimeglumine enhancement in hilar cholangiocarcinoma. MATERIALS AND METHODS: Twenty-four patients (14 men, 10 women; aged 27-78 years; mean age, 51 years) with hilar cholangiocarcinoma underwent TZ-weighted spin-echo MR imaging in the axial plane and multisection, breath-hold, fast low-angle shot (FLASH) MR imaging in the coronal oblique plane before and at 30, 60, 90, and 120 seconds after bolus injection of gadopentetate dimeglumine. Morphologic features were recorded, and contrast medium enhancement characteristics and contrast-to-noise ratios were calculated for each sequence. RESULTS: All the lesions were hyperintense on T2-weighted spin-echo images and hypointense on FLASH images. On dynamic gadolinium-enhanced images, progressive heterogeneous enhancement was seen in all patients. Intrahepatic ductal dilatation was present in every patient. Intraluminal components were seen in 11 patients, lobar atrophy in 12, and segmental portal venous occlusion or stenosis in 13. Satellite lesions were present in four patients, and hilar lymph nodal enlargement in 11. Contrast-to-noise ratios were statistically significantly higher on T2-weighted spin-echo images than on all other images. CONCLUSION: Hilar cholangiocarcinomas have consistent enhancement and morphologic features that can be demonstrated with dynamic contrast-enhanced MR imaging.