Vinicius Rocha-Santos

LATE ACUTE REJECTION IN LIVER TRANSPLANT: A SYSTEMATIC REVIEW

Introduction: Late acute rejection leads to worse patient and graft survival after liver transplantation. Aim: To analyze the reported results published in recent years by leading transplant centers in evaluating late acute rejection and update the clinical manifestations, diagnosis and treatment of liver transplantation. Method: Systematic literature review through Medline-PubMed database with headings related to late acute rejection in articles published until November 2013 was done. Were analyzed demographics, immunosuppression, rejection, infection and graft and patient survival rates. Results: Late acute rejection in liver transplantation showed poor results mainly regarding patient and graft survival. Almost all of these cohort studies were retrospective and descriptive. The incidence of late acute rejection varied from 7-40% in these studies. Late acute rejection was one cause for graft loss and resulted in different outcomes with worse patient and graft survival after liver transplant. Late acute rejection has been variably defined and may be a cause of chronic rejection with worse prognosis. Late acute rejection occurs during a period in which the goal is to maintain lower immunosuppression after liver transplantation. Conclusion: The current articles show the importance of late acute rejection. The real benefit is based on early diagnosis and adequate treatment at the onset until late follow up after liver transplantation.

Pentoxifylline enhances the protective effects of hypertonic saline solution on liver ischemia reperfusion injury through inhibition of oxidative stress.

BACKGROUND Liver ischemia reperfusion (IR) injury triggers a systemic inflammatory response and is the main cause of organ dysfunction and adverse postoperative outcomes after liver surgery. Pentoxifylline (PTX) and hypertonic saline solution (HTS) have been identified to have beneficial effects against IR injury. This study aimed to investigate if the addition of PTX to HTS is superior to HTS alone for the prevention of liver IR injury. METHODS Male Wistar rats were allocated into three groups. Control rats underwent 60 minutes of partial liver ischemia, HTS rats were treated with 0.4 mL/kg of intravenous 7.5% NaCl 15 minutes before reperfusion, and HPTX group were treated with 7.5% NaCl plus 25 mg/kg of PTX 15 minutes before reperfusion. Samples were collected after reperfusion for determination of ALT, AST, TNF-alpha, IL-6, IL-10, mitochondrial respiration, lipid peroxidation, pulmonary permeability and myeloperoxidase. RESULTS HPTX significantly decreased TNF-alpha 30 minutes after reperfusion. HPTX and HTS significantly decreased ALT, AST, IL-6, mitochondrial dysfunction and pulmonary myeloperoxidase 4 hours after reperfusion. Compared with HTS only, HPTX significantly decreased hepatic oxidative stress 4 hours after reperfusion and pulmonary permeability 4 and 12 hours after reperfusion. CONCLUSION This study showed that PTX added the beneficial effects of HTS on liver IR injury through decreases of hepatic oxidative stress and pulmonary permeability.

Re-Transplantation, Higher Creatinine Levels in Hepatitis C Virus Patients, and Donor Age Are Predictors of Mortality in Long-Term Analysis of Late Acute Rejection in Liver Transplantation

BACKGROUND Late acute rejection (LAR) differs in its clinical and histological presentation and management from early acute rejection. This clinical entity is not completely understood; thus, we aimed to identify significant prognostic factors that can influence post-transplant survival in LAR patients. The purpose of this study was to evaluate the incidence and post-transplant survival of patients from a single center with a focus on late acute rejection. MATERIAL AND METHODS From January 2002 to June 2013, all liver biopsies from patients with rejection were scored using the Banff criteria. The groups were compared, and simple and multiple logistic regression and survival curves were created. RESULTS A total of 779 liver transplants were performed; 585 patients with no rejections and 194 patients with rejections were analyzed. The overall incidence of LAR was 6.7%, and there was a higher prevalence of early acute cellular rejection than LAR. The mean time to LAR was 564 days (median 214 days, range 91-2642). LAR had a more severe grade (35.3%) than early acute rejection (23.5%). The survival rates were similar between both modalities for the long-term period. Worse mortality rates were observed in liver re-transplantation (HR 4.77; p<0.0001); in hepatitis C virus patients with increased creatinine levels (HR 22.48; p=0.016); and in donors >41 years of age (OR 2.1; p=0.047) in a long-term analysis of LAR. CONCLUSIONS Liver re-transplantation, higher creatinine levels in hepatitis C virus patients, and donor age were predictors of mortality in this long-term analysis of late acute rejection in liver transplantation.

Immunotherapy against endocrine malignancies: immune checkpoint inhibitors lead the way

Immune checkpoint inhibitors are agents that act by inhibiting the mechanisms of immune escape displayed by various cancers. The success of immune checkpoint inhibitors against several tumors has promoted a new treatment strategy in clinical oncology, and this has encouraged physicians to increase the number of patients who receive the immune checkpoint therapy. In the present article, we review the main concepts regarding immune checkpoint mechanisms and how cancer disrupts them to undergo immune escape. In addition, we describe the most essential concepts related to immune checkpoint inhibitors. We critically review the literature on preclinical and clinical studies of the immune checkpoint inhibitors as a treatment option for thyroid cancer, ovarian carcinoma, pancreatic adenocarcinoma, adrenocortical carcinoma and neuroendocrine tumors. We present the challenges and the opportunities of using immune checkpoint inhibitors against these endocrine malignancies, highlighting the breakthroughs and pitfalls that have recently emerged.

Living donor liver transplantation for hepatocellular cancer: An (almost) exclusive Eastern procedure?

Hepatocellular carcinoma (HCC) is the fifth most prevalent cancer and it is linked with chronic liver disease. Liver transplantation (LT) is the best curative treatment modality, since it can cure simultaneously the underlying liver disease and HCC. Milan criteria (MC) are the benchmark for selecting patients with HCC for LT, achieving up to 91% 1-year survival post transplantation. However, when considering intention-to-treat (ITT) rates are substantially lower, mainly due dropout. Additionally, Milan criteria (MC) are too restrictive and more inclusive criteria have been reported with good outcomes. Mainly, in Eastern countries, deceased donors are scarce, therefore Asian centers have developed living-donor liver transplantation (LDLT) to a state-of-art status. There are many eastern centers reporting huge numbers of LDLT with outstanding results. Regarding HCC patients, they have reported many criteria including more advanced tumors achieving reasonable outcomes. Western countries have well-established deceased-donor liver transplantation (DDLT) programs. However, organ shortage and restrictive criteria for listing patients with HCC endorses LDLT as a good option to offer curative treatment to more HCC patients. However, there are some controversial reports claiming higher rates of HCC recurrence after LDLT than DDLT. An extensive review included 30 studies with cohorts of HCC patients who underwent LDLT in both East and West countries. We reported also the results of our Institution, in Brazil, where it was performed the first LDLT. This review also addresses the eligibility criteria for transplanting patients with HCC developed in Western and Eastern countries.

Resection for intrahepatic cholangiocellular cancer: new advances

Intrahepatic cholangiocarcinoma (ICC) is the second most prevalent primary liver neoplasm after hepatocellular carcinoma (HCC), corresponding to 10% to 15% of cases. Pathologies that cause chronic biliary inflammation and bile stasis are known predisposing factors for development of ICC. The incidence and cancer-related mortality of ICC is increasing worldwide. Most patients remain asymptomatic until advance stage, commonly presenting with a liver mass incidentally diagnosed. The only potentially curative treatment available for ICC is surgical resection. The prognosis is dismal for unresectable cases. The principle of the surgical approach is a margin negative hepatic resection with preservation of adequate liver remnant. Regional lymphadenectomy is recommended at time of hepatectomy due to the massive impact on outcomes caused by lymph node (LN) metastasis. Multicentric disease, tumor size, margin status and tumor differentiation are also important prognostic factors. Staging laparoscopy is warranted in high-risk patients to avoid unnecessary laparotomy. Exceedingly complex surgical procedures, such as major vascular, extrahepatic bile ducts and visceral resections, ex vivo hepatectomy and autotransplantation, should be implemented in properly selected patients to achieve negative margins. Neoadjuvant therapy may be used in initially unresectable lesions in order to downstage and allow resection. Despite optimal surgical management, recurrence is frustratingly high. Adjuvant chemotherapy with radiation associated with locoregional treatments should be considered in cases with unfavorable prognostic factors. Selected patients may undergo re-resection of tumor recurrence. Despite the historically poor outcomes of liver transplantation for ICC, highly selected patients with unresectable disease, especially those with adequate response to neoadjuvant therapy, may be offered transplant. In this article, we reviewed the current literature in order to highlight the most recent advances and recommendations for the surgical treatment of this aggressive malignancy.

Imatinib-induced fulminant liver failure in chronic myeloid leukemia: role of liver transplant and second-generation tyrosine kinase inhibitors: a case report

BackgroundThere is a worldwide problem of acute liver failure and mortality associated with remaining on the waiting for a liver transplant. In this study, we highlight results published in recent years by leading transplant centers in evaluating imatinib-induced acute liver failure in chronic myeloid leukemia and follow-up in liver transplantation.Case presentationA 36-year-old brown-skinned woman (mixed Brazilian race) diagnosed 1 year earlier with chronic myeloid leukemia was started after delivery of a baby and continued for 6 months with imatinib mesylate (selective inhibitor of Bcr-Abl tyrosine kinase), which induced liver failure. We conducted a literature review using the PubMed database for articles published through September 2017, and we demonstrate a role of liver transplant in this situation for imatinib-induced liver failure. We report previously published results and a successful liver transplant after acute liver failure due to imatinib-induced in chronic myeloid leukemia treatment.ConclusionsWe report a case of a successful liver transplant after acute liver failure resulting from imatinib-induced chronic myeloid leukemia treatment. The literature reveals the importance of prompt acute liver failure diagnosis and treatment with liver transplant in selected cases.

Liver biopsy may facilitate pancreatic graft evaluation: Positive association between liver steatosis and pancreatic graft adipose infiltration

OBJECTIVES: The number of pancreatic transplants has decreased in recent years. Pancreatic grafts have been underutilized compared to other solid grafts. One cause of discard is the macroscopic appearance of the pancreas, especially the presence of fatty infiltration. The current research is aimed at understanding any graft-related association between fatty tissue infiltration of the pancreas and liver steatosis. METHODS: From August 2013 to August 2014, a prospective cross-sectional clinical study using data from 54 multiple deceased donor organs was performed. RESULTS: Micro- and macroscopic liver steatosis were significantly correlated with the donor body mass index ([BMI]; p=0.029 and p=0.006, respectively). Positive gamma associations between pancreatic and liver macroscopic and microscopic findings (0.98; confidence interval [CI]: 0.95–1 and 0.52; CI 0.04–1, respectively) were observed. Furthermore, comparisons of liver microscopy findings showed significant differences between severe versus absent (p<0.001), severe versus mild (p<0.001), and severe versus moderate classifications (p<0.001). The area under the receiver operating curve was 0.94 for the diagnosis of steatosis by BMI evaluation using a cut-off BMI of 27.5 kg/m2, which yielded 100% sensitivity, 87% specificity, and 100% negative predictive value. CONCLUSIONS: We observed a positive association of macroscopic and microscopic histopathological findings in steatotic livers with adipose infiltration of pancreatic grafts.

Gastric fundus submucosa as a site for islets transplantation: An experimental study

Background Islets of Langerhans transplantation is a promising alternative for glycemic control in patients with type 1 diabetes. The graft site is a factor that has large impact on the functioning of this transplant, and the stomach appears to be a promising location. Our objective is to describe a new experimental model for the grafting of Islets of Langerhans in rat stomachs. Methodology Islets of Langerhans were extracted from 45 isogenic male rats of the Lewis lineage and transplanted into 9 isogenic rats of the Wistar lineage; 5 in the gastric body submucosa, and 4 in the gastric fundus submucosa. Normoglycemia was defined as two successive measurements of <250 mg/dL. No immunosuppression was used. The two groups glycemia control improvement were compared with t-student test. Results The results obtained following the transplantation of the islets in 9 rats showed between 995 and 2310 islets transplanted (mean of 1367). The rats from the gastric submucosa group had a better glycemic level improvement, with a confidence equal to 83.94%. Conclusion Islets graft into the gastric fundus submucosa is a viable model with potential for adequate glycemic control. This model gives potential for new perspectives and future studies in this area.

Laparoscopic cholecystectomy and cirrhosis: patient selection and technical considerations

The incidence of cholelithiasis in cirrhotic patients is higher than in general population. In the past, open cholecystectomy (OC) was the standard approach for patients requiring cholecystectomy. However, laparoscopic cholecystectomy (LC) was introduced in 1980’s and gradually became the preferred technique even to cirrhotic patients. The performance of gastrointestinal surgery procedures in cirrhotics patients is well-known to be associated with higher technical difficulty and increased morbidity-mortality. Cirrhosis is a major key intraoperative finding that contributes to surgical difficulty in LC. Model of End Stage Liver Disease (MELD) score and Child-Pugh Classification are the best devices to evaluate the underlying liver disease and to predict morbidity-mortality. Acute cholecystitis has higher incidence in patients with cirrhosis, emergency procedures in cirrhotics patients are associated with higher morbidity, longer postoperative hospitalization and a seven-fold higher mortality in comparison to elective surgery. LC in cirrhotics has a higher conversion rate to open procedure; however, LC demonstrated substantial advantage over OC providing shorter convalescence period and hospital stay.