Hepatectomy for Hilar Cholangiocarcinoma with Right-Sided Ligamentum Teres Using a Hepatectomy Simulation System

Right-sided ligamentum teres (RSLT) is a rare congenital anomaly often accompanied by variation of the hepatic vasculature. We herein report a surgical case of a hilar cholangiocarcinoma with RSLT in whom preoperative hepatectomy simulation proved useful for understanding the anatomical structure of the liver. A 78-year-old male with obstructive jaundice was referred to our department for further examination. The patient was suspected of having a hilar cholangiocarcinoma originating from the left hepatic bile duct by contrast-enhanced computed tomography (CT), and CT also showed right umbilical portion (RUP). Three-dimensional images of the hepatic vasculature and biliary system reconstructed using a hepatectomy simulation system suggested that all portal branches ramified from RUP were right paramedian branches, and three leftward portal branches from these ran parallel to the peripheral bile ducts confluent with the left hepatic bile duct, where the tumor was present. Hepatic resection of part of the ventral area of the right paramedian sector and left hemiliver was performed along the demarcation line drawn after clamping the portal branches; the ratio of estimated liver resection volume was 28.9%. After the operation, bile leakage occurred. However, the leakage was treated with percutaneous drainage alone, and the patient was discharged 77 days after the operation. The patient is doing well without any signs of recurrence 21 months after the operation. The vascular and biliary anatomy in patients with RSLT is complicated and should be evaluated in detail preoperatively using a hepatectomy simulation system

Multifocal Mass Lesions in Autoimmune Pancreatitis

A 59-year-old male patient with jaundice was referred to our hospital because of mass lesions in the pancreatic head and tail. An immunological examination revealed an elevated serum IgG4 level. Computed tomography showed two clear boundary mass lesions in the pancreatic head and tail. Magnetic resonance imaging showed that the mass lesions exhibited low intensity on T1-weighted images and iso-intensity on T2-weighted images. Magnetic resonance cholangiopancreatography showed an obstruction of the main pancreatic duct in the pancreatic head and tail. The possibility of malignant tumors could not be ruled out; therefore, we performed total pancreatectomy. A histopathological examination of the nodular lesions revealed severe lymphoplasmacytic infiltration and inflammatory change around the pancreatic ducts. Immunohistochemistry revealed diffuse infiltration of IgG4-positive plasma cells in the nodules. According to these pathological findings, we diagnosed the patient with IgG4-related multifocal mass lesions of autoimmune pancreatitis (AIP). It is difficult to distinguish between focal type AIP and pancreatic cancer. We herein report a rare case of multifocal mass lesions in AIP and include bibliographical comments

Laparoscopic Resection of an Epithelial Cyst in an Intrapancreatic Accessory Spleen

An epithelial cyst in an intrapancreatic accessory spleen (ECIAS) is rare. We herein report a case of a patient with ECIAS who underwent laparoscopic surgery. A 57-year-old woman was referred to our hospital because of a pancreatic tail tumor. She was asymptomatic, and a physical examination revealed no remarkable abnormalities. The levels of the tumor marker carbohydrate antigen 19-9 (CA19-9) and s-pancreas-1 antigen (SPan-1) were elevated. Ultrasonography showed a well-defined homogeneous cystic tumor. Computed tomography showed a well-demarcated cystic tumor in the pancreatic tail. Magnetic resonance imaging showed that the cystic tumor exhibited low intensity on T1-weighted images and high intensity on T2-weighted images. The cystic tumor was diagnosed as mucinous cystic neoplasm preoperatively. The patient underwent laparoscopic spleen-preserving distal pancreatectomy. A histopathological examination revealed the cyst wall to be lined by stratified squamous epithelium within splenic parenchyma, and the ultimate diagnosis was ECIAS. The postoperative course was uneventful, and the patient was discharged on postoperative day 12. ECIAS is very difficult to diagnose preoperatively. Laparoscopic surgery is a safe and minimally invasive procedure for patients with difficult-to-diagnose pancreatic tail tumor suspected of having low-grade malignancy

Hepatic Pseudolymphoma with Fluorodeoxyglucose Uptake on Positron Emission Tomography

A 69-year-old woman with chronic hepatitis B was admitted to our hospital with a hepatic tumor. The levels of 2 tumor markers, carcinoembryonic antigen and carbohydrate antigen 19-9, were slightly elevated; however, the α-fetoprotein and protein levels induced by vitamin K antagonist II were within the normal limits. Abdominal ultrasonography showed a well-defined peripheral hypoechoic mass that was isoechoic and homogeneous on the inside. Computed tomography showed a poorly enhanced tumor of 13 mm in diameter in the 5th segment of the liver. Fluorodeoxyglucose positron emission tomography showed a slight uptake (maximum standard uptake value 3.4) by the hepatic tumor. These findings suggested cholangiocellular carcinoma, and we performed anterior segmentectomy of the liver. A histopathological examination showed a hepatic pseudolymphoma. The patient’s postoperative course was uneventful, and she remains alive without recurrence 5 months after undergoing surgery. In most cases, hepatic pseudolymphoma is preoperatively diagnosed as a malignant tumor and a definite diagnosis is made after resection. It is therefore necessary to consider hepatic pseudolymphoma as a differential diagnosis in patients with hepatic tumors