A 68-year-old man presented with intermittent right upper quadrant (RUQ) abdominal pain for half a year. Additionally, a temperature of up to 38.3 C occurred more than a month ago with no apparent cause. Upon arrival, he admitted having diabetes for three years, treated with metformin and glimepiride. His vital signs were stable upon initial evaluation. There is no evidence of a family history of cancer. The patient had a long history of alcohol abuse (daily consumption of >250 g alcohol over the past 30 years). Physical examination revealed no noteworthy findings other than abdominal pain. Tumor markers revealed elevated alpha-fetoprotein (AFP) levels (7.03 ng/ml) and des-gamma-carboxy prothrombin (DCP) levels (33.0 mAU/ml). A complete hemogram showed elevated RDW-CV and AMC levels, and decreased RBC, HGB, HCT, and LY% levels. Liver function tests showed elevated ALT, AST, GGT, and glucose levels and decreased TP and albumin levels. Renal function tests showed elevated serum cystatin C levels. A complete hemogram, liver function, and renal function tests of the patient are presented in  Table 1 . Laboratory tests also showed positive E antibody and core antibody.
A contrast-enhanced computed tomography (CT) scan of the upper abdomen displayed multiple slightly low-density masses and mixed-density nodules in the left lobe and the anterior segment of the right lobe. The largest mass was measured at 11.2 x 8.5 cm from an axial view. Lesions showed ring enhancement in the arterial phase and continuous enhancement in the portal phase. The sagittal part of the portal vein was infiltrated. Dilatation of the left intrahepatic bile duct combined with bile duct stones was observed. In addition, there were enlarged lymph nodes in the hepatic portal, portacaval space, and around the abdominal aorta ( Figure 1 ).
A preoperative diagnosis of cholangiocarcinoma was made. Resection of the left lateral lobe, left medial lobe, right anterior lobe, and caudate lobe of the liver, hilar cholangioplasty, and cholecystectomy were performed to remove the whole mass after two days of admission, which appeared to have a complete tumor margin, a yellowish cross-section, and dilated partial bile ducts with stones inside. A lymphadenectomy was not performed. The operative time was 228 min. The blood loss was 500 cc, and a perioperative blood transfusion was not required. Surgical samples were taken and sent for pathological examination. There were no immediate postoperative complications.
Histopathological analysis revealed that tumors were rich in osteoclast-like giant cells and neoplastic spindle-shaped cells ( Figures 2A, B ). Complete hepatic-lobule-like structures, edema of hepatocytes, intrahepatic cholestasis, lymphocyte, and plasma cell infiltration in the portal area were observed in the non-tumorous liver parenchyma of the resected specimen. Immunohistochemical staining showed that tumor cells were negative for EMA, Hepa, CK (Pan) ( Figures 3A-C ), desmin, CD34, S-100, SATB2, P63, P16, GS, GPC3, and CAM5.2, but positive for SMA, P53, Ki-67 (30%), ACT, CK8/18 ( Figures 4A, B ), and vimentin. PCR and Sanger sequencing: no H3F3A gene mutation was detected. Combined with histopathology and immunohistochemistry, the diagnosis of undifferentiated carcinoma with osteoclast-like giant cells of the liver was considered. The possibility of metastatic tumors was excluded by a comprehensive clinical examination.
The postoperative situation of the patient was stable, and he was discharged on the 12th day. At the first follow-up two months after hospital discharge, a chest CT showed that the lymph nodes in the mediastinum and right diaphragmatic corner were significantly increased. The patients and their families refused gene tests and agreed to perform GA chemotherapy was temporarily performed (gemcitabine 1.5 g d1; d8 + albumin paclitaxel 200 mg d1; d8). At the second follow-up five months after hospital discharge, metastases were found on CT scans of the head and chest. The patient and his family still refused the gene test and chose to undergo GP chemotherapy (gemcitabine 1,600 mg d1, 8 ivgtt + cisplatin 40 mg d1, 8; Q3w) and radiotherapy for the head. The current vital signs of the patient are stable. The patient is alive after 5-month follow-up.