Impact of hypoxic preconditioning on apoptosis and its possible mechanism in orthotopic liver autotransplantation in rats

BACKGROUND: Hepatocyte apoptosis is a severe form of cell death after hepatic ischemia-reperfusion injury (HIRI), and its relief is an important issue in liver transplantation. Hypoxic preconditioning (HP) is considered to have protective effects on HIRI. This study was designed to explore the impact of HP on apoptosis and its possible mechanism during orthotopic liver autotransplantation. METHODS: A modified orthotopic liver autotransplantation model was used to simulate HIRI. Sprague-Dawley rats were randomly divided into normal control, autotransplantation (AT) and HP groups. The HP group was subjected to an 8% oxygen atmosphere for 90 minutes before surgery. At 1, 6 and 24 hours after surgery, the rats were killed and their liver tissue was sampled to assess the expression of Bcl-2 protein. The samples were subjected to blood chemistry study, morphological study under a light or transmission electron microscope, and quantitative study of mitochondria. RESULTS: The serum levels of ALT and AST in the HP group were lower than those in the AT group at 1, 6 and 24 hours after orthotopic liver autotransplantation (P < 0.05). Bcl-2 protein expression was increased in the HP group at each measurement point (P < 0.05). Light microscopy showed that hepatic injury in the AT group was much more severe than in the HP group. Hepatocytes in the AT group showed typical apoptosis signs under a transmission electron microscope. The ultrastructural appearance of hepatocytes in the HP group was much better than in the AT group, and the area, perimeter and diameter of the mitochondria were smaller in the HP group than in the AT group (P < 0.05). CONCLUSIONS: Hepatocytes sense and respond to decreased tissue oxygenation. Stimulation by HP relieves apoptosis by upregulating expression of Bcl-2 protein and its protection of mitochondria after orthotopic liver autotransplantation.

Clinical Outcomes of Ex Vivo Liver Resection and Liver Autotransplantation for Hepatic Alveolar Echinococcosis

The effectiveness of liver autotransplantation for patients with partial hepatic alveolar echinococcosis was analyzed.We retrospectively studied 6 patients with hepatic alveolar echinococcosis who underwent liver autotransplantation in our hospital from 2008 to 2010.We also summarized the surgical indications of liver autotransplantation for hepatic alveolar echinococcosis and our experience in the management of postoperative complications of liver autotransplantation.Of 6 patients,5 achieved good curative results,and one died of multiple organ failure caused by portal vein thrombosis.Main complications included postoperative bleeding,bile leak and small-for-size liver graft syndrome.Liver autotransplantation offers a new approach to cure hepatic alveolar echinococcosis with non-resectable lesions.It could be the most effective method to cure intractable hepatic alveolar echinococcosis if correct handling in operation and proper prevention of complications are performed.But the long-term outcomes are still needed to be confirmed in longer follow-up.

The consensus on liver autotransplantation from an international panel of experts

IntroductionMore than 1.0 million patients worldwide are diagnosed with space-occupying lesions in the liver every year, with the number approaching 0.5 million per year in China, and only 20% of the lesions are resectable Due to a lack of available donors, only a limited number of patients underwent allogeneic liver transplantation, the remaining patients simply receive palliative care. Therefore, discovering new options for treating these patients is a high priority. Liver autotransplantation （LAT） is a surgical technique that adopts liver transplantation skills to radically treat spaceoccupying hepatic lesions, benign or malignant,

Systematic sequential therapy for ex vivo liver resection and autotransplantation: A case report and review of literature

BACKGROUND Perihilar cholangiocarcinoma(pCCA)is a highly malignant tumor arising from the biliary tree.Radical surgery is the only treatment offering a chance of long-term survival.However,limited by the tumor’s anatomic location and peri-vascular invasion,most patients lose the chance for curative treatment.Therefore,more methods to increase the resectability of tumors as well as to improve outcomes are needed.CASE SUMMARY A 68-year-old female patient had a hepatic hilar mass without obvious symptoms.Laboratory results showed hepatitis B positivity.Magnetic resonance imaging indicated that the mass(maximum diameter:41 mm)invaded the left and right branches of the main portal vein,as well as the middle,left and right hepatic veins;enlarged lymph nodes were also detected in the hilum.The patient was diagnosed with pCCA,and the clinical stage was determined to be T4N1M0(stage IIIC).Considering the tumor’s anatomic location and vascular invasion,systematic conversion therapy followed by ex vivo liver resection and autotrans-plantation(ELRA)was determined as personalized treatment for this patient.Our original systemic sequential therapeutic strategy(lenvatinib and tislelizumab in combination with gemcitabine and cisplatin)was successfully adopted as conversion therapy because she achieved partial response after three cycles of treatment,without severe toxicity.ELRA,anastomotic reconstruction of the middle hepatic vein,right hepatic vein,root of portal vein,inferior vena cava and right hepatic artery,and lymph node dissection were performed at one month after systemic therapy.Pathological and immunohistochemical examination confirmed the diagnosis of pCCA with lymph node metastasis.Although the middle hepatic vein was partially obstructed four months later,hepatic vein stent implantation successfully addressed this problem.The patient has survived for 22 mo after the diagnosis,with no evidence of recurrence or metastasis.CONCLUSION An effective therapeutic strategy for conversion therapy greatly increases the feasibility and efficiency of ELRA.

Complex inferior vena cava reconstruction during ex vivo liver resection and autotransplantation:A case report

BACKGROUND Ex vivo liver resection and autotransplantation(ELRA)is an essential approach for treating patients with end-stage hepatic alveolar echinococcosis(AE),and its surgical indications involve severe invasion of important hepatic vessels,which makes in vivo resection impossible.Revascularization is a major step in the process of ELRA,which is extremely challenging when the invaded vessels have huge defects.CASE SUMMARY Herein,we have reported the case of a 26-year-old patient with hepatic AE in an autologous liver graft who underwent complex inferior vena cava(IVC)reconstruction using disease-free IVC,autologous portal vein fragments,and umbilical vein within the ligamentum teres hepatis.The patient showed good surgical recovery without vascular-related complications during the long-term follow-up.CONCLUSION We reviewed three studies that have reported complex revascularization of the IVC.This case report and systematic review showed that the use of autologous perihepatic vessels prevents donor-area trauma,immune rejection,and other adverse reactions.When the blood vessel is severely invaded and a single vascular material cannot repair and reconstruct the defect,ELRA may provide a safe and feasible surgical approach,which has good prospects for clinical application.

Ex vivo liver resection and auto-transplantation and special systemic therapy in perihilar cholangiocarcinoma treatment

This editorial contains comments on the article“Systematic sequential therapy for ex vivo liver resection and autotransplantation:A case report and review of li-terature”in the recent issue of World Journal of Gastrointestinal Surgery.It points out the actuality and importance of the article and focuses primarily on the role and place of ex vivo liver resection and autotransplantation(ELRAT)and systemic therapy,underlying molecular mechanisms for targeted therapy in perihilar cho-langiocarcinoma(pCCA)management.pCCA is a tough malignancy with a high proportion of advanced disease at the time of diagnosis.The only curative option is radical surgery.Surgical excision and reconstruction become extremely com-plicated and not always could be performed even in localized disease.On the other hand,ELRAT takes its place among surgical options for carefully selected pCCA patients.In advanced disease,systemic therapy becomes a viable option to prolong survival.This editorial describes current possibilities in chemotherapy and reveals underlying mechanisms and projections in targeted therapy with ki-nase inhibitors and immunotherapy in both palliative and adjuvant settings.Fi-broblast grow factor and fibroblast grow factor receptor,human epidermal grow-th factor receptor 2,isocitrate dehydrogenase,and protein kinase cAMP activated catalytic subunit alpha(PRKACA)and beta(PRKACB)pathways have been ac-tively investigated in CCA in last years.Several agents were introduced and approved by the Food and Drug Administration.They all demonstrated mean-ingful activity in CCA patients with no global change in outcomes.That is why every successfully treated patient counts,especially those with advanced disease.In conclusion,pCCA is still hard to treat due to late diagnosis and extremely complicated surgical options.ELRAT also brings some hope,but it could be performed in very carefully selected patients.Advanced disease requires systemic anticancer treatment,which is supposed to be individualized according to the genetic and molecular features of cancer cells.Targeted therapy in combination with chemo-immunotherapy could be effective in susceptible patients.

A new veno-venous bypass type for ex-vivo liver resection in dogs

Ex-vivo liver resection is a procedure in which the liver is completely removed, perfused and after bench surgery, the liver is autotransplanted to the original site. Ex vivo liver resection is an important treatment for unresectable liver tumors. This surgical procedure requires long operation time, during which blood flow must be carefully maintained to avoid venous congestion. An effective veno-venous bypass (VVB) may meet this requirement. The present study was to test our new designed VVB device which comprised one heparinized polyvinylchloride tube and three magnetic rings The efficacy of this device was tested in five dogs. A VVB was established in 6-10 minutes. There was no leakage during the procedure. Hemodynamics was stable at anhepatic phase, which indicated that the bypass was successful. This newly-developed VVB device maintained circulation stability during ex-vivo liver resection in our dog model and thus, this VVB device significantly shortened the operation time.

Ex vivo liver resection followed by autotransplantation for end-stage hepatic alveolar echinococcosis

Background For patients with end-stage hepatic alveolar echinococcosis （AE）, in vivo resection of the involved parts of the liver is usually very difficult, therefore, allogenic liver transplantation is indicated. However, we hypothesize that for selected patents, ex vivo liver resection for thorough elimination of the involved tissues and liver autotransplantation may offer a chance for clinical cure. Methods We presented a 24-year-old women with a giant hepatic AE lesion who was treated with hepatectomy, ex vivo resection of the involved tissue and hepatic autotransplantation. The patient had moderate jaundice and advanced hepatic AE lesion which involved segments I, IV, V, VI, VII, VIII and retrohepatic inferior vena cava. The lateral segments （II and III） of the left liver remained normal with over 1000 ml in its volume. No extrahepatic metastases （such as to the lung or brain） could be found. As the first step of treatment, X-ray guided percutaneous transhepatic cholangiodrainage （PTCD） was performed twice for bile drainage in segment III and II separately until her serum total bilirubin decreased gradually from 236 to 88 umol/L. Total liver resection was then performed, followed by extended right hepatic trisegmentectomy and the entire retrohepatic vena cava was surgically removed en bloc while her hemodynamics parameters were stable. Neither veino-veinous bypass nor temporary intracorporeal cavo-caval or porto-caval shunt was used during the 5.7-hour anhepatic phase. The remained AE-free lateral segments of the-left liver were re-implanted in situ. The left hepatic vein was directly anastomosed end-to-end to the suprahepatic inferior vena cava due to the lack of the retrohepatic inferior vena cava with AE total infiltration. Because compensatory retroperitoneal porto-caval collateral circulation developed, we enclosed remained infrahepatic inferior vena cava at renal vein level without any haemodynamics problems. Results During a 60-day following-up after operation, the patient had a good recovery except for a mildly elevated serum total bilirubin. Conclusions As a radical approach, ex vivo liver resection and liver autotransptantation in a case has shown a optimal potential for treatment of the end-stage hepatic AE. Strict compliance with its indications, evaluation of vessels of patients pre-operatively, and precise surgical techniques are the keys to improve the prognosis of patients.