Yoshikazu Toyoki

FGF3/FGF4 amplification and multiple lung metastases in responders to sorafenib in hepatocellular carcinoma

The response rate to sorafenib in hepatocellular carcinoma (HCC) is relatively low (0.7%‐3%), however, rapid and drastic tumor regression is occasionally observed. The molecular backgrounds and clinico‐pathological features of these responders remain largely unclear. We analyzed the clinical and molecular backgrounds of 13 responders to sorafenib with significant tumor shrinkage in a retrospective study. A comparative genomic hybridization analysis using one frozen HCC sample from a responder demonstrated that the 11q13 region, a rare amplicon in HCC including the loci for FGF3 and FGF4, was highly amplified. A real‐time polymerase chain reaction–based copy number assay revealed that FGF3/FGF4 amplification was observed in three of the 10 HCC samples from responders in which DNA was evaluable, whereas amplification was not observed in 38 patients with stable or progressive disease (P = 0.006). Fluorescence in situ hybridization analysis confirmed FGF3 amplification. In addition, the clinico‐pathological features showed that multiple lung metastases (5/13, P = 0.006) and a poorly differentiated histological type (5/13, P = 0.13) were frequently observed in responders. A growth inhibitory assay showed that only one FGF3/FGF4‐amplified and three FGFR2‐amplified cancer cell lines exhibited hypersensitivity to sorafenib in vitro. Finally, an in vivo study revealed that treatment with a low dose of sorafenib was partially effective for stably and exogenously expressed FGF4 tumors, while being less effective in tumors expressing EGFP or FGF3. Conclusion: FGF3/FGF4 amplification was observed in around 2% of HCCs. Although the sample size was relatively small, FGF3/FGF4 amplification, a poorly differentiated histological type, and multiple lung metastases were frequently observed in responders to sorafenib. Our findings may provide a novel insight into the molecular background of HCC and sorafenib responders, warranting further prospective biomarker studies. (HEPATOLOGY 2013)

Influence of cold ischemia time and graft transport distance on postoperative outcome in human liver transplantation.

Abstract.Purpose: The association between hepatic allograft cold ischemia time (CIT) and graft transport distance (GTD) in human liver transplantation was examined by investigating whether extended graft transportation prolongs the CIT and adversely affects graft survival.Methods: We retrospectively analyzed 186 consecutive orthotopic liver transplants (OLTs) done between May 1997 and July 1998. The number of miles from the donor hospital to the University of Pittsburgh Medical Center in a straight line was measured in each case, and defined as the GTD. The OLTs were divided into two groups according to whether the GTD was ≤200 miles or >200 miles. The latter group was then subdivided into groups of GTD 200–400 miles, GTD 400–600 miles, and GTD >600 miles. The CIT and graft outcome within 90 days after OLT were assessed.Results: Extended GTD prolonged the CIT (P < 0.001). The rate of hepatic allograft loss in the long GTD group was significantly higher than that in the short GTD group (P= 0.018). When the OLTs were subdivided according to GTD, the CIT increased and graft survival decreased as the GTD extended. Hepatic allograft transportation for a long distance prolonged the CIT and decreased the graft survival rate.Conclusion: Since prolonged CIT is a major risk factor, avoiding long-distance graft transportation is recommended when the donor risk factors are high.

Expression of MRP2 and MRP3 during liver regeneration after 90% partial hepatectomy in rats.

Background. Small-for-size grafts often cause persistent conjugated hyperbilirubinemia in the recipient after adult-to-adult living donor liver transplantation, but the cause has not yet been clarified. In physiologic status, bilirubin is excreted from hepatocytes to the bile canaliculus by means of multidrug resistance protein (MRP) 2 and, in particular circumstances, by means of MRP3 to the sinusoidal space. The aim of this study was to research whether there is any change in bilirubin excretion pattern during liver regeneration with reference to expression of MRP2 and MRP3. Methods. Sprague-Dawley rats underwent sham operation (n=37), 70% hepatectomy (n=38), or 90% hepatectomy (n=37). The degree of liver regeneration, total and direct bilirubin, protein synthesis, and interleukin (IL)-6 were serially assessed. Expression of MRP2 and MRP3 were semiquantified by Western blotting. Results. The proliferating cell nuclear antigen labeling index indicated rapid liver regeneration after 70% and 90% hepatectomy. Serum levels of total and direct bilirubin increased significantly (P <0.05), and conjugated hyperbilirubinemia was proved only in the 90% hepatectomy group. Coagulation factor VII dipped but increased as early as 12 to 24 hr postoperatively in both hepatectomy groups. Plasma IL-6 levels were significantly increased in the 90% hepatectomy group (P <0.05). Expression of MRP2 was decreased and MRP3 was expressed at 36 and 72 hr postoperatively in the 90% hepatectomy group, whereas no change was observed in MRP expression in the 70% hepatectomy group. Conclusions. During liver regeneration after critical hepatectomy such as 90% hepatectomy, decrease of MRP2 and expression of MRP3 may play an important role in postoperative hyperbilirubinemia.

The effects of intraportal prostaglandin E1 administration on hepatic warm ischemia and reperfusion injury in dogs.

To determine the route of prostaglandin E1 (PGE1) administration which would have the greatest protective effect against hepatic warm ischemia, two experiments were performed using dogs. The pharmacokinetics of PGE1 were investigated in a preliminary study, after which, the effects of PGE1 in a 90-min warm ischemic liver model were examined. The dogs were divided into three groups of ten, according to the treatment given: group A was an untreated control group, group B received PGE1 intravenously, and group C received PGE1 intraportally. The PGE1 was infused continuously at a rate of 0.02 μg/kg/min before and after ischemia. All the dogs in groups A and B died within 24 h of induced ischemia. Whereas, six of the ten dogs in group C survived for over 3 days. The arterial ketone body ratio was not maintained in groups A and B, but it was in group C. Furthermore, in group C the serum lipid peroxide level, which reflects hepatocellular membrane damage, was maintained at a lower level than that in the other groups after ischemia. Electron microscopy revealed sinusoid destruction and changes in both the plasma membrane and parenchymal cell mitochondria in groups A and B, while in group C these structures were well preserved. These findings confirmed that intraportally administered PGE1 improved the hepatic microcirculation and stabilized the hepatocellular membranes. Our results indicate that intraportal administration of PGE1 has a greater protective effect than intravenous administration against warm ischemic liver injury.

Allograft rejection in pediatric liver transplantation: Comparison between cadaveric and living related donors

Abstract: The aim of this study was to determine whether living related liver transplantation has an immunological advantage compared with cadaveric liver transplants in children. The records of 100 pediatric primary liver transplant recipients performed between January 1992 and December 1998 at the University of California, San Francisco Medical Center, were reviewed retrospectively. Ten children who died or required a second graft within the first 14 post‐operative days were excluded from this study group. Two children with combined kidney‐liver transplants were also excluded. As a result, the study group included 51 children in the cadaveric liver transplantation (CLT) group and 37 children in the living‐related liver transplantation (LRLT) group. Until 1995, primary immunosuppression consisted of cyclosporin A, azathioprine and steroids. Since 1995, primary immunosuppression consisted of cyclosporin A, mycophenolate mofetil and steroids. Actuarial graft survival rates at 1, 2 and 5 yrs were 90%, 80.9% and 80.9% in the CLT group vs. 94.6%, 91.6% and 78.5% in the LRLT group, respectively (NS). Rejection was diagnosed in 40 of 51 cadaveric first grafts (78.4%) and 25 of 37 living‐related primary grafts (67.6%). Rejection episodes were diagnosed greater than 1 yr post‐transplantation in 11 of 51 cadaveric first grafts (21.6%) and none of 37 living‐related primary grafts (0%) (p < 0.05). LRLT succeeded in reducing the immunosuppressive therapy compared with CLT at 24 months after transplantation (p < 0.05). The overall incidence of rejection and graft survival rate were comparable in CLT and LRLT; however, rejection episodes in LRLT recipients diagnosed greater than 1 yr post‐transplant were significantly fewer than CLT recipients. LRLT have a partial immunological advantage compared with CLT.

Hepatic venous outflow obstruction in living donor liver transplantation: balloon angioplasty or stent placement?

BACKGROUND The incidence of hepatic venous outflow obstruction (HVOO) has been reported to be 5%-13% when a partial graft is used for orthotopic liver transplantation (OLT). HVOO leads to graft congestion, portal hypertension, and finally cirrhosis, which jeopardizes both graft and recipient survivals. In this study, we sought to identify perioperative factors influencing HVOO and to investigate conditions that require stent placement. PATIENTS AND METHODS From February 1994 to December 2010, we performed 40 living donor liver transplantations (LDLT). HVOO occurred in 5 cases (12.5%), all of which were left lobe grafts. Because HVOO was not observed in patients with body weight (BW) <30 kg, we investigated the other 28 cases with BW >30 kg. RESULTS There was no difference from unaffected subjects except for cold ischemic time (CIT), which was significantly longer: 86.2 ± 10.4 minutes vs 46.0 ± 4.8 minutes (P = .001). Balloon angioplasty, which was selected as the initial treatment for all stricture patients, improved 2 patients after 1 and 5 treatments, respectively, but 3 subjects underwent repeated HVOO, finally being treated with self-expandable metallic stents at 9, 6, and 10 years after LDLT, respectively. All patients finally resolved their strictures. CONCLUSION HVOO reflects intimal hyperplasia and fibrosis at the anastomotic sites or compression and twisting of the anastomosis caused by graft regeneration. In addition, progression of chronic rejection and fibrosis are possibly responsible for late-onset HVOO. Longer CIT possibly reflects difficulties in the venoplasty before anastomosis. No bleeding or thrombosis complications were observed during dilatation among our cases. The selection of the stent size for each case and careful stent deployment are important to prevent complications. Stent placement should be considered in patients with chronic rejection who are refractory to several balloon angioplasties with early-onset or late-onset HVOO.

Usefulness of in-phase and out-of-phase magnetic resonance imaging for the detection of pancreatic lymphoepithelial cyst.

Lymphoepithelial cyst (LEC) of the pancreas is a rare benign lesion that may mimic cystic neoplasms. Diagnosis of pancreatic LEC has been depended on the elevation of serum carbohydrate antigen 19-9 (CA 19-9), biopsy of the cyst by endoscopic ultrasonography (EUS) and several abdominal imaging techniques including magnetic resonance imaging (MRI). However, it is very difficult to diagnose LEC of the pancreas preoperatively and excessive surgery has been done in spite of its benign nature. We herein report a case of pancreatic LEC which was preoperatively diagnosed by using in-phase and out-of-phase MRI and was successfully nucleated.

Laparoscopic treatment for biliary ascariasis.

Biliary ascariasis is one of the most common types of ascaris infections. The current treatments are helminthic drug therapy, endoscopic extraction, and surgical extraction. A case of biliary ascariasis and cholecystocholedocholithiasis was successfully treated by laparoscopic extraction of the living worm and biliary stones. This procedure was found to be very effective for biliary ascariasis with biliary stones, and it holds promise for similar cases in the future.

Radical operation for hilar cholangiocarcinoma in comparable Eastern and Western centers: Outcome analysis and prognostic factors

Background: Extensive resection for hilar cholangiocarcinoma is the most effective treatment, but high morbidity and poor prognosis remain concerns. Previous data have shown marked differences in outcomes between comparable Eastern and Western centers. We compared the outcomes of the management for hilar cholangiocarcinoma at one Japanese and one British institution with comparable experience. Methods: Of 298 consecutive patients with hilar cholangiocarcinoma evaluated at Hirosaki University Hospital, Japan and St. Jamess University Hospital, Leeds, UK, 183 underwent radical resection. Clinicopathologic variables and postoperative outcomes were compared. Results: Significant differences were not observed between the Hirosaki and Leeds cohorts in overall outcomes despite several differences in the patient characteristics. Although there was a difference in 90‐day mortality (2.5% vs 13.6%, respectively), disease‐specific 5‐year survival rates were 32.8% and 31.9%, respectively (P = .767). Multivariate analysis identified trisectionectomy (odds ratio = 2.32; P = .010), combined pancreatoduodenectomy (odds ratio = 7.88; P = .010), and perioperative blood transfusion (odds ratio = 1.88; P = .045) were associated with postoperative major complications, while preoperative biliary drainage associated with postoperative major complications, while preoperative biliary drainage (risk ratio = 2.21; P = .018), perioperative blood transfusion (risk ratio = 1.58; P = .029), lymph node metastasis (risk ratio = 2.00; P = .002), moderate/poorly differentiated tumor (risk ratio = 1.72; P = .029), microvascular invasion (risk ratio = 1.63; P = .046), and R1 resection (risk ratio = 1.90; P = .005) were risk factors for poor survival. Conclusion: Disease‐specific survival and prognostic factors were similar in both centers. Meticulous operative technique to avoid perioperative blood transfusion may improve long‐term survival.

Liver Transplantation for Wilson's Disease in Pediatric Patients: Decision Making and Timing

Transplantation for Wilsons disease occupies 1/3 of the cases for metabolic diseases in Japan. At the end of 2009, 109 transplantations had been performed including three deceased donor cases in the Japanese registry. We herein discuss problems of transplantation for Wilsons disease as well as its indication, timing, and social care. We retrospectively reviewed four fulminant cases and two chronic cases who underwent living donor liver transplantation. There were two boys and two girls. Four adolescents of average age 11.3 years underwent living donor liver transplantation. Duration from onset to transplantation ranged from 10 to 23 days. Average Model for End-stage Liver Disease (MELD) score was 27.8 (range=24-31). All patients were administrated chelates prior to transplantation. MELD, New Wilsons index, Japanese scoring for liver transplantation, and liver atrophy were useful tools for transplantation decision making; however, none of them was an independent decisive tool. Clinical courses after transplantation were almost uneventful. One girl, however, developed an acute rejection episode due to noncompliance at 3 years after transplantation. All patients currently survive without a graft loss. No disease recurrence had been noted even using living related donors. Two adults evaluated for liver transplantation were listed for deceased donor liver transplantation. Both candidates developed cirrhosis despite long-term medical treatment. There were no appropriate living donors for them. There are many problems in transplantation for Wilsons disease. The indications for liver transplantation should be considered individually using some decision-making tools. The safety of the living donor should be paid the most attention.