Yukio Oshiro

A Nationwide Survey of Hepatitis E Virus Infection and Chronic Hepatitis E in Liver Transplant Recipients in Japan

Background Recently, chronic hepatitis E has been increasingly reported in organ transplant recipients in European countries. In Japan, the prevalence of hepatitis E virus (HEV) infection after transplantation remains unclear, so we conducted a nationwide cross-sectional study to clarify the prevalence of chronic HEV infection in Japanese liver transplant recipients. Methods A total of 1893 liver transplant recipients in 17 university hospitals in Japan were examined for the presence of immunoglobulin G (IgG), IgM and IgA classes of anti-HEV antibodies, and HEV RNA in serum. Findings The prevalence of anti-HEV IgG, IgM and IgA class antibodies was 2.9% (54/1893), 0.05% (1/1893) and 0% (0/1893), respectively. Of 1651 patients tested for HEV RNA, two patients (0.12%) were found to be positive and developed chronic infection after liver transplantation. In both cases, HEV RNA was also detected in one of the blood products transfused at the perioperative period. Analysis of the HEV genomes revealed that the HEV isolates obtained from the recipients and the transfused blood products were identical in both cases, indicating transfusion-transmitted HEV infection. Interpretation The prevalence of HEV antibodies in liver transplant recipients was 2.9%, which is low compared with the healthy population in Japan and with organ transplant recipients in European countries; however, the present study found, for the first time, two Japanese patients with chronic HEV infection that was acquired via blood transfusion during or after liver transplantation.

A novel three-dimensional print of liver vessels and tumors in hepatectomy

Creating a three-dimensional (3D)-printed liver model is costly, and the visibility of the inner structures is slightly hindered. We developed a novel structure that simultaneously solves both of these problems. The outer frames were set up along the liver surface. Our structure did not use the transparent loading material because this material increases the printing cost. Therefore, we were able to directly observe the inside of the structure. We performed hepatectomy using this novel 3D-printed liver model. Using this model, we were able to clearly simulate the resection line and safely perform the surgery. Our process was more cost effective, had a shorter production time, and improved the visibility than other processes. We developed a novel 3D-printed liver for hepatectomy, which made the procedure easier, reduced the production cost, and improved the visibility; this approach may be useful for future surgeries.

Novel 3-dimensional virtual hepatectomy simulation combined with real-time deformation

AIM To develop a novel 3-dimensional (3D) virtual hepatectomy simulation software, Liversim, to visualize the real-time deformation of the liver. METHODS We developed a novel real-time virtual hepatectomy simulation software program called Liversim. The software provides 4 basic functions: viewing 3D models from arbitrary directions, changing the colors and opacities of the models, deforming the models based on user interaction, and incising the liver parenchyma and intrahepatic vessels based on user operations. From April 2010 through 2013, 99 patients underwent virtual hepatectomies that used the conventional software program SYNAPSE VINCENT preoperatively. Between April 2012 and October 2013, 11 patients received virtual hepatectomies using the novel software program Liversim; these hepatectomies were performed both preoperatively and at the same that the actual hepatectomy was performed in an operating room. The perioperative outcomes were analyzed between the patients for whom SYNAPSE VINCENT was used and those for whom Liversim was used. Furthermore, medical students and surgical residents were asked to complete questionnaires regarding the new software. RESULTS There were no obvious discrepancies (i.e., the emergence of branches in the portal vein or hepatic vein or the depth and direction of the resection line) between our simulation and the actual surgery during the resection process. The median operating time was 304 min (range, 110 to 846) in the VINCENT group and 397 min (range, 232 to 497) in the Liversim group (P = 0.30). The median amount of intraoperative bleeding was 510 mL (range, 18 to 5120) in the VINCENT group and 470 mL (range, 130 to 1600) in the Liversim group (P = 0.44). The median postoperative stay was 12 d (range, 6 to 100) in the VINCENT group and 13 d (range, 9 to 21) in the Liversim group (P = 0.36). There were no significant differences in the preoperative outcomes between the two groups. Liversim was not found to be clinically inferior to SYNAPSE VINCENT. Both students and surgical residents reported that the Liversim image was almost the same as the actual hepatectomy. CONCLUSION Virtual hepatectomy with real-time deformation of the liver using Liversim is useful for the safe performance of hepatectomies and for surgical education.

Three-dimensional imaging identified the accessory bile duct in a patient with cholangiocarcinoma.

The development of diagnostic imaging technology, such as multidetector computed tomography (MDCT) and magnetic resonance cholangiopancreatography (MRCP), has made it possible to obtain detailed images of the bile duct. Recent reports have indicated that a 3-dimensional (3D) reconstructed imaging system would be useful for understanding the liver anatomy before surgery. We have investigated a novel method that fuses MDCT and MRCP images. This novel system easily made it possible to detect the anatomical relationship between the vessels and bile duct in the portal hepatis. In this report, we describe a very rare case of extrahepatic cholangiocarcinoma associated with an accessory bile duct from the caudate lobe connecting with the intrapancreatic bile duct. We were unable to preoperatively detect this accessory bile duct using MDCT and MRCP. However, prior to the second operation, we were able to clearly visualise the injured accessory bile duct using our novel 3D imaging modality. In this report, we suggest that this imaging technique can be considered a novel and useful modality for understanding the anatomy of the portal hepatis, including the hilar bile duct.

Clinical Features of Hepatitis E Virus Infection in Ibaraki, Japan: Autochthonous Hepatitis E and Acute-on-Chronic Liver Failure

Hepatitis E caused by hepatitis E virus (HEV) is a serious public health concern in developing countries where HEV is mainly transmitted through contaminated water. Recently, in industrialized countries, autochthonous hepatitis E, a porcine zoonosis, has been increasingly recognized. In Japan, the number of national notifications of acute hepatitis E has increased since the introduction of anti-HEV IgA antibody measurement, covered by the national health insurance program, in 2011. In the past three years, we examined five patients of acute hepatitis or acute-on-chronic liver failure caused by HEV infection who presented various clinical courses in the southern area of Ibaraki prefecture in Japan. Of these patients, 78-year-old and 63-year-old male patients presented acute hepatitis E and recovered by only bed rest. The latter patient had a history of consuming grilled or undercooked pork and shellfish prior to the onset of hepatitis E. Among the five patients examined, the infection route was detected only in this patient. Of note, a 65-year-old female patient presented severe hepatitis associated with painless thyroiditis. The patient was diagnosed with probable autoimmune hepatitis and was successfully treated with prednisolone (40 mg/day). Lastly, 58-year-old and 62-year-old male patients, both of whom had a history of diabetes mellitus and alcoholic liver disease, developed acute-on-chronic liver failure, and the latter patient with pre-existing liver cirrhosis died due to liver failure. Thus, patients with clinical HEV infection who display multiple underlying diseases can develop acute-on-chronic liver failure. In conclusion, HEV infection manifests the diverse clinical courses.

A novel preoperative fusion analysis using three-dimensional MDCT combined with three-dimensional MRI for patients with hilar cholangiocarcinoma

The purpose of the present study was to evaluate the anatomical relationship between the tumor, portal veins, hepatic arteries, and hilar hepatic ducts at the hepatic hilum using a novel preoperative fusion analysis for patients with hilar cholangiocarcinoma. This involved combining three-dimensional multidetector-row computed tomography with three-dimensional magnetic resonance imaging. This novel fusion imaging technique can play an important clinical role for patients undergoing surgery for hilar cholangiocarcinoma.

Adjuvant surgery for advanced extrahepatic cholangiocarcinoma

Patients with Stage IV cholangiocarcinoma are currently not considered to be surgical candidates and are typically offered systemic chemotherapy. Recently, several novel systemic chemotherapy regimens have allowed an initially unresectable cholangiocarcinoma to be resectable. The aim of this article is to present the usefulness of adjuvant surgery in a case of advanced cholangiocarcinoma that was successfully treated with gemcitabine. A 72-year-old man was diagnosed with distal cholangiocarcinoma with liver metastases (cT2N0M1, Stage IV). He underwent metal stent placement in the duodenum to alleviate jaundice. After 18 courses of chemotherapy using gemcitabine without severe drug toxicities, a computed tomography scan showed that the liver metastases in S6 and S7 had disappeared. The patient underwent subtotal stomach-preserving pancreaticoduodenectomy and lymph node dissection. The pathological stage was pT2N0M0, Stage IB. The patient underwent 6 cycles of adjuvant chemotherapy using gemcitabine. The patient is alive and well 6 years and 9 mo after the diagnosis.

Well-differentiated endocrine carcinoma originating from the bile duct in association with a congenital choledochal cyst.

We encountered a rare case of a well-differentiated endocrine carcinoma originating from the bile duct in association with a congenital choledochal cyst (CCC). The patient is a 28-year-old woman referred to our clinic for pruritus. Laboratory data showed mild elevation of serum hepatobiliary enzymes. Computed tomography and magnetic resonance imaging demonstrated pancreatobiliary maljunction and a Todani type IV-A CCC from the inferior bile duct to the bilateral intrahepatic bile ducts. A solid tumor was detected in the middle portion of the common bile duct. Pancreatoduodenectomy and total extrahepatic bile duct resection was performed. Based on pathologic and immunohistochemical examinations, a diagnosis of well-differentiated endocrine carcinoma was made according to the World Health Organization criteria. To our knowledge, this is the third report of a neuroendocrine tumor originating from the bile duct in association with a CCC.

Neuroendocrine carcinoma of the extrahepatic bile duct: A case report.

Neuroendocrine carcinoma (NEC) originating from the gastrointestinal hepatobiliary-pancreas is a rare, invasive, and progressive disease, for which the prognosis is extremely poor. The patient was a 72-year-old man referred with complaints of jaundice. He was diagnosed with middle extrahepatic cholangiocarcinoma (cT4N1M0, cStage IV). He underwent a right hepatectomy combined with extrahepatic bile duct and portal vein resection after percutaneous transhepatic portal vein embolization. Microscopic examination showed a large-cell neuroendocrine carcinoma according to the WHO criteria for the clinicopathologic classification of gastroenteropancreatic neuroendocrine tumors. Currently, the patient is receiving combination chemotherapy with cisplatin and etoposide for postoperative multiple liver metastases. Although NEC is difficult to diagnose preoperatively, it should be considered an uncommon alternative diagnosis.

Postoperative Decrease in Platelet Counts Is Associated with Delayed Liver Function Recovery and Complications after Partial Hepatectomy

Peripheral platelet counts decrease after partial hepatectomy; however, the implications of this phenomenon are unclear. We assessed if the observed decrease in platelet counts was associated with postoperative liver function and morbidity (complications grade ≤ II according to the Clavien-Dindo classification). We enrolled 216 consecutive patients who underwent partial hepatectomy for primary liver cancers, metastatic liver cancers, benign tumors, and donor hepatectomy. We classified patients as either low or high platelet percentage (postoperative platelet count/preoperative platelet count) using the optimal cutoff value calculated by a receiver operating characteristic (ROC) curve analysis, and analyzed risk factors for delayed liver functional recovery and morbidity after hepatectomy. Delayed liver function recovery and morbidity were significantly correlated with the lowest value of platelet percentage based on ROC analysis. Using a cutoff value of 60% acquired by ROC analysis, univariate and multivariate analysis determined that postoperative lowest platelet percentage ≤ 60% was identified as an independent risk factor of delayed liver function recovery (odds ratio (OR) 6.85; P < 0.01) and morbidity (OR, 4.90; P < 0.01). Furthermore, patients with the lowest platelet percentage ≤ 60% had decreased postoperative prothrombin time ratio and serum albumin level and increased serum bilirubin level when compared with patients with platelet percentage ≥ 61%. A greater than 40% decrease in platelet count after partial hepatectomy was an independent risk factor for delayed liver function recovery and postoperative morbidity. In conclusion, the decrease in platelet counts is an early marker to predict the liver function recovery and complications after hepatectomy.