Case 1. Patient male, 73 years old 2. Complaint: liver metastasis of gallbladder cancer for half a month, sleeping for one hour 3. Brief medical history: persistent chest pain, epigastric pain, poor appetite, accompanied by low fever, cold sweat, general weakness, not related to activity, rest and medication are not effective, stool once in more than 10 days, weight loss about 10 Kg. 4. Abdominal ultrasound: solid occupancy of the liver (Ca is considered likely); gallbladder wall is not significantly elevated; hyperechoic reflection in the gallbladder (Ca is considered likely, further examination is recommended); lymph nodes in the hilum; pancreas, spleen, and both kidneys are not significantly elevated; pancreas, spleen, and both kidneys are recommended. (further examination is recommended); irregular elevation of gallbladder wall; hyperechoic reflection in gallbladder (Ca is considered likely, further examination is recommended); enlarged lymph nodes in the hilar region; no obvious abnormalities in pancreas, spleen and both kidneys Image manifestations Normal morphology and size of liver, hepatic fissure is not wide, the edges are bright and neat, large lamellar hypointense shadow in liver parenchyma, unclear boundary, uneven density, obvious enhancement in the arterial phase in enhancement scan, and decreased enhancement in the venous phase. There was no significant dilatation of the bile ducts inside and outside the liver. The boundary of the gallbladder wall was unclear, and an elliptical slightly dense shadow was seen inside. The spleen was normal in size, and the parenchymal density was equal and uniformly enhanced. The pancreatic gland was normal in size and shape, with equal and uniform parenchymal density and enhancement, and clear fatty shadow in the peripancreatic space. The renal morphology and size of both kidneys were not significantly abnormal, and the renal parenchyma was uniformly enhanced, with clear perinephric space. There were no obvious enlarged lymph nodes in the retroperitoneum and no obvious signs of fluid accumulation in the abdominal cavity. The diagnosis was that the liver parenchyma was a huge occupancy with a high possibility of malignancy. Slightly dense shadow in the gallbladder, considering stones and not excluding tumor. Gallbladder cancer is the most common malignant tumor in the biliary system, with unknown etiology and no symptoms in the early stage, making diagnosis difficult. The progressive stage often shows persistent pain in the right upper abdomen, jaundice, emaciation, liver enlargement and upper abdominal masses, and fever, nausea and vomiting in combination with cholecystitis Pathology Mostly occurs in the base or neck of gallbladder, The tumor may also metastasize distantly through the hepatic artery, portal vein, and bile ducts through lymphatic channels to the hilar, mesenteric, and retroperitoneal lymph nodes. CT enhancement v The mass and thickened gallbladder wall are obviously enhanced Other Bile duct dilatation, stenosis, gallbladder stones, lymph node enlargement MRI presentation Similar to CT presentation, it shows a substantial mass with low signal in T1WI and slightly high signal in T2WI in the gallbladder. irregular high signal bands may appear in the liver parenchyma around the mass on T2WI, suggesting tumor invasion of the liver. It also shows lymph node metastasis and bile duct dilatation. Ultrasound and CT are the most commonly used imaging methods for gallbladder cancer, both of which can easily show irregular thickening of the gallbladder wall and masses of different sizes in the gallbladder cavity, and most of them are not difficult to diagnose. Arteriography is less commonly used; in advanced stages, MRCP has diagnostic value in observing gallbladder cancer invading bile ducts. Mass-type gallbladder cancer that has spread to the surrounding liver parenchyma is easily confused with hepatocellular carcinoma. The bile duct invasion caused by gallbladder cancer is more obvious and dilated; on the contrary, bile duct dilatation occurs less in hepatocellular carcinoma, and more portal vein invasion and tumor thrombus are present. Gallbladder wall thickening type of gallbladder cancer also needs to be differentiated from cholecystitis, and the diagnosis of gallbladder cancer is supported by the obvious irregular thickening of gallbladder wall, obvious enhancement by contrast-enhanced CT, obvious bile duct dilatation, surrounding liver parenchyma invasion and intrahepatic metastasis.