Evaluation Study Of Peripheral Cholangiocarcinoma And Hepatocellular Carcinoma Examined By MR

The MRI features of peripheral cholangiocarcinoma (PCC) and heptocellacar carcinoma (HCC) were analyzed retrospectively, especially in dynamic contrast-enhanced MRI, in order to get more valuable imging information to help their diagnosis and differential diagnosis each other. Materials and Methods1. MR scanning results of 14 cases of PCC and 24 cases of HCC, which were confirmed histopathologically after operation, were analyzed in the study.2. Dynamic contrast-enhanced MR images of whole liver were obtained with 2D FMSPGR sequence. Gd-DTPA was given through cubital vein by high-pressure injection apparatus.Results1. MRI features of peripheral cholangiocarcinoma (PCC) The PCC lesions showed low signal on T1WI and uneven high signal interest on T2WI. A low attenuation spherical slight irregular ring like enhanced lesions structure on dynamic contrast-enhanced images during the hepatic arterial phase (HAP) were observed. Gradual intensity enhanced lesions were observed during the portal venous phase (PVP) and the equilibrium phase. Continuous enhanced lesions were showed during the postpone phase.2. MR images of hepatocellular carcinoma (HCC)The PCC lesions showed low signal on T1WI, and high signal on T2WI. Uneven significant enhanced lesion on dynamic contrast-enhanced images during the HAP was observed these. Rapidly decreasing intensity was observed during the PHVP. Low signal intensity was observed during the equilibrium phase and the postpone phase and there was no significant difference between tumor and the arround liver parenchyma.3. Comparison of the clinical findings and those MR imaging information between PCC and HCC(1) Patients with PCC usually have positive CEA level and biliary diseases, and patients with HCC usually have positive AFP, HBV and hepatic cirrhosis.(2) Significant contrast-enhanced lesions were observed in HCC images during the HAP, but that not in PCC. Significant intensity was observed in PCC images during the postpone phase, but that didn't change significantly in HCC.(3) Biliary signs in local lesions, intrahepatobiliary enlargement and metastasis of lymph nodes were usually showed in PCC images. Pseudomembranous signs and infiltrations of hepatic portal vein were the main features showed in HCC.Conclusions1. Patients with PCC usually have positive CEA and biliarydiseases, and patients with HCC usually have positive AFP, HBV and hepatic cirrhosis.2. PCC lesions showed low signal on T1WI, and high signal T2-weighted. But those were not showed in HCC images.3. Significant contrast enhancement was observed in most HCC, during the HAP, but that not in PCC, observed in PCC images during the postpone phase, but that didn't change significantly on HCC images. There were significant differences between the two characteristics.4. Metastases of the porta hepatis and retroperitoneal lymph-nodes usually occur in PCC, but cancerous thrombosis of hepatic or portal vein usually take place in HCC, Biliary signs in local lesions and intrahepatobiliary enlargement were also the one of the main features on MRI showed in PCC. Pseudomembranous sign was the typical feature in HCC.The differences between PCC and HCC not only in the clinical findings but also in MR imaging characteristics could provide useful information for their diagnosis and differential diagnosis.