Ali Zarrinpar

Liver transplantation for nonalcoholic steatohepatitis: the new epidemic.

Objective:To analyze incidence, outcomes, and utilization of health care resources in liver transplantation (LT) for nonalcoholic steatohepatitis (NASH). Summary of Background Data:With the epidemic of obesity and metabolic syndrome in nearly 33% of the US population, NASH is projected to become the leading indication for LT in the next several years. Data on predictors of outcome and utilization of health care resources after LT in NASH is limited. Methods:We conducted an analysis from our prospective database of 144 adult NASH patients who underwent LT between December 1993 and August 2011. Outcomes and resource utilization were compared with other common indications for LT. Independent predictors of graft and patient survival were identified. Results:The average Model for End-Stage Liver Disease score was 33. The frequency of NASH as the primary indication for LT increased from 3% in 2002 to 19% in 2011 to become the second most common indication for LT at our center behind hepatitis C. NASH patients had significantly longer operative times (402 vs 322 minutes; P < 0.001), operative blood loss (18 vs 14 packed red blood cell units; P = 0.001), and posttransplant length of stay (35 vs 29 days; P = 0.032), but 1-, 3-, and 5-year graft (81%, 71%, 63%) and patient (84%, 75%, 70%) survival were comparable with other diagnoses. Age greater than 55 years, pretransplant intubation, dialysis, hospitalization, presence of hepatocellular carcinoma on explant, donor age greater than 55 years, and cold ischemia time greater than 550 minutes were significant independent predictors of survival for all patients, whereas body mass index greater than 35 was a predictor in NASH patients only. Conclusions:We report the largest single institution experience of LT for NASH. Over a 10-year period, the frequency of LT for NASH has increased 5-fold. Although outcomes are comparable with LT for other indications, health care resources are stressed significantly by this new and increasing group of transplant candidates.

The evolution of liver transplantation during 3 decades: analysis of 5347 consecutive liver transplants at a single center.

Objective:To analyze a 28-year single-center experience with orthotopic liver transplantation (OLT) for patients with irreversible liver failure. Background:The implementation of the model for end-stage liver disease (MELD) in 2002 represented a fundamental shift in liver donor allocation to recipients with the highest acuity, raising concerns about posttransplant outcome and morbidity. Methods:Outcomes and factors affecting survival were analyzed in 5347 consecutive OLTs performed in 3752 adults and 822 children between 1984 and 2012, including comparisons of recipient and donor characteristics, graft and patient outcomes, and postoperative morbidity before (n = 3218) and after (n = 2129) implementation of the MELD allocation system. Independent predictors of survival were identified. Results:Overall, 1-, 5-, 10-, and 20-year patient and graft survival estimates were 82%, 70%, 63%, 52%, and 73%, 61%, 54%, 43%, respectively. Recipient survival was best in children with biliary atresia and worst in adults with malignancy. Post-MELD era recipients were older (54 vs 49, P < 0.001), more likely to be hospitalized (50% vs 47%, P = 0.026) and receiving pretransplant renal replacement therapy (34% vs 12%, P < 0.001), and had significantly greater laboratory MELD scores (28 vs 19, P < 0.001), longer wait-list times (270 days vs 186 days, P < 0.001), and pretransplant hospital stays (10 days vs 8 days, P < 0.001). Despite increased acuity, post-MELD era recipients achieved superior 1-, 5-, and 10-year patient survival (82%, 70%, and 65% vs 77%, 66%, and 58%, P < 0.001) and graft survival (78%, 66%, and 61% vs 69%, 58%, and 51%, P < 0.001) compared with pre-MELD recipients. Of 17 recipient and donor variables, era of transplantation, etiology of liver disease, recipient and donor age, prior transplantation, MELD score, hospitalization at time of OLT, and cold and warm ischemia time were independent predictors of survival. Conclusions:We present the worlds largest reported single-institution experience with OLT. Despite increasing acuity in post-MELD era recipients, patient and graft survival continues to improve, justifying the “sickest first” allocation approach.

Liver transplantation: past, present and future

The first human liver transplant operation was performed by Thomas Starzl in 1963. The next two decades were marked by difficulties with donor organ quality, recipient selection, operative and perioperative management, immunosuppression and infectious complications. Advances in each of these areas transformed liver transplantation from an experimental procedure to a standard treatment for end-stage liver disease and certain cancers. From the handful of pioneering programmes, liver transplantation has expanded to hundreds of programmes in >80 countries. 1-year patient survival rates have exceeded 80% and outcomes continue to improve. This success has created obstacles. Ongoing challenges of liver transplantation include those concerning donor organ shortages, recipients with more advanced disease at transplant, growing need for retransplantation, toxicities and adverse effects associated with long-term immunosuppression, obesity and NASH epidemics, HCV recurrence and the still inscrutable biology of hepatocellular carcinoma. This Perspectives summarizes this transformation over time and details some of the challenges ahead.

A Novel Prognostic Nomogram Accurately Predicts Hepatocellular Carcinoma Recurrence after Liver Transplantation: Analysis of 865 Consecutive Liver Transplant Recipients

BACKGROUND Although radiologic size criteria (Milan/University of California, San Francisco [UCSF]) have led to improved outcomes after liver transplantation (LT) for hepatocellular carcinoma (HCC), recurrence remains a significant challenge. We analyzed our 30-year experience with LT for HCC to identify predictors of recurrence. STUDY DESIGN A novel clinicopathologic risk score and prognostic nomogram predicting post-transplant HCC recurrence was developed from a multivariate competing-risk Cox regression analysis of 865 LT recipients with HCC between 1984 and 2013. RESULTS Overall patient and recurrence-free survivals were 83%, 68%, 60% and 79%, 63%, and 56% at 1-, 3-, and 5-years, respectively. Hepatocellular carcinoma recurred in 117 recipients, with a median time to recurrence of 15 months, involving the lungs (59%), abdomen/pelvis (38%), liver (35%), bone (28%), pleura/mediastinum (12%), and brain (5%). Multivariate predictors of recurrence included tumor grade/differentiation (G4/poor diff hazard ratio [HR] 8.86; G2-3/mod-poor diff HR 2.56), macrovascular (HR 7.82) and microvascular (HR 2.42) invasion, nondownstaged tumors outside Milan criteria (HR 3.02), nonincidental tumors with radiographic maximum diameter ≥ 5 cm (HR 2.71) and <5 cm (HR 1.55), and pretransplant neutrophil-to-lymphocyte ratio (HR 1.77 per log unit), maximum alpha fetoprotein (HR 1.21 per log unit), and total cholesterol (HR 1.14 per SD). A pretransplantation model incorporating only known radiographic and laboratory parameters had improved accuracy in predicting HCC recurrence (C statistic 0.79) compared with both Milan (C statistic 0.64) and UCSF (C statistic 0.64) criteria alone. A novel clinicopathologic prognostic nomogram included explant pathology and had an excellent ability to predict post-transplant recurrence (C statistic 0.85). CONCLUSIONS In the largest single-institution experience with LT for HCC, excellent long-term survival was achieved. Incorporation of routine pretransplantation biomarkers to existing radiographic size criteria significantly improves the ability to predict post-transplant recurrence, and should be considered in recipient selection. A novel clinicopathologic prognostic nomogram accurately predicts HCC recurrence after LT and may guide frequency of post-transplantation surveillance and adjuvant therapy.

Complete pathologic response to pretransplant locoregional therapy for hepatocellular carcinoma defines cancer cure after liver transplantation: analysis of 501 consecutively treated patients.

OBJECTIVES To evaluate the rate, effect, and predictive factors of a complete pathologic response (cPR) in patients with hepatocellular carcinoma (HCC) undergoing locoregional therapy (LRT) before liver transplantation (LT). BACKGROUND Eligible patients with HCC receive equal model for end-stage liver disease prioritization, despite variable risks of tumor progression, waitlist dropout, and posttransplant recurrence. Pretransplant LRT mitigates these risks by inducing tumor necrosis. METHODS Comparisons were made among HCC recipients with cPR (n = 126) and without cPR (n = 375) receiving pre-LT LRT (1994-2013). Multivariable predictors of cPR were identified. RESULTS Of 501 patients, 272, 148, and 81 received 1, 2, and 3 or more LRT treatments. The overall, recurrence-free, and disease-specific survival at 1-, 3-, and 5 years was 86%, 71%, 63%; 84%, 67%, 60%; and 97%, 90%, 87%. Compared with recipients without cPR, cPR patients had significantly lower laboratory model for end-stage liver disease scores, pretransplant alpha fetoprotein, and cumulative tumor diameters; were more likely to have 1 lesion, tumors within Milan/University of California, San Francisco (UCSF) criteria, LRT that included ablation, and a favorable tumor response to LRT; and had superior 1-, 3-, and 5-year recurrence-free survival (92%, 79%, and 73% vs 81%, 63%, and 56%; P = 0.006) and disease-specific survival (100%, 100%, and 99% vs 96%, 89%, and 86%; P < 0.001) with only 1 cancer-specific death and fewer recurrences (2.4% vs 15.2%; P < 0.001). Multivariate predictors of cPR included a favorable post-LRT radiologic/alpha fetoprotein tumor response, longer time interval from LRT to LT, and lower model for end-stage liver disease score and maximum tumor diameter (C-statistic 0.75). CONCLUSIONS Achieving cPR in patients with HCC receiving LRT strongly predicts tumor-free survival. Factors predicting cPR are identified, allowing for differential prioritization of HCC recipients based on their variable risks of post-LT recurrence. Improving LRT strategies to maximize cPR would enhance posttransplant cancer outcomes.

Liver transplantation for hepatocellular carcinoma: an update.

BACKGROUND Hepatocellular carcinoma (HCC) is a heterogeneous malignancy with multiple etiologies, high incidence, and high mortality. The standard surgical management for patients with HCC consists of locoregional ablation, surgical resection, or liver transplantation, depending on the background state of the liver. Eighty percent of patients initially presenting with HCC are unresectable, either due to the extent of tumor or the level of underlying hepatic dysfunction. While in patients with no evidence of cirrhosis and good hepatic function resection has been the surgical treatment of choice, it is contraindicated in patients with moderate to severe cirrhosis. Liver transplantation is the optimal surgical treatment. DATA SOURCES PubMed search of recent articles (from January 2000 to March 2011) was performed looking for relevant articles about hepatocellular carcinoma and its treatment. Additional articles were identified by evaluating references from selected articles. RESULTS Here we review criteria for transplantation, the types, indications, and role of locoregional therapy in treating the cancer and in downstaging for possible later transplantation. We also summarize the contribution of immunosuppression and adjuvant chemotherapy in the management and prevention of HCC recurrence. Finally we discuss recent advances in imaging, tumor biology, and genomics as we delineate the remaining challenges for the diagnosis and treatment of this disease. CONCLUSIONS Much can be improved in the diagnosis and treatment of HCC. A great challenge will be to improve patient selection to criteria based on tumor biology. Another will be to incorporate systemic agents post-operatively in patients at high risk for recurrence, paying close attention to efficacy and safety. The future direction of the effort in treating HCC will be to stimulate prospective trials, develop molecular imaging of lymphovascular invasion, to improve recipient selection, and to investigate biomarkers of tumor biology.

Assessment of hepatic steatosis by transplant surgeon and expert pathologist: A prospective, double‐blind evaluation of 201 donor livers

An accurate clinical assessment of hepatic steatosis before transplantation is critical for successful outcomes after liver transplantation, especially if a pathologist is not available at the time of procurement. This prospective study investigated the surgeons accuracy in predicting hepatic steatosis and organ quality in 201 adult donor livers. A steatosis assessment by a blinded expert pathologist served as the reference gold standard. The surgeons steatosis estimate correlated more strongly with large‐droplet macrovesicular steatosis [ld‐MaS; nonparametric Spearman correlation coefficient (rS) = 0.504] versus small‐droplet macrovesicular steatosis (sd‐MaS; rS = 0.398). True microvesicular steatosis was present in only 2 donors (1%). Liver texture criteria (yellowness, absence of scratch marks, and round edges) were mainly associated with ld‐MaS (variance = 0.619) and were less associated with sd‐MaS (variance = 0.264). The prediction of ≥30% ld‐MaS versus <30% ld‐MaS was excellent when liver texture criteria were used (accuracy = 86.2%), but it was less accurate when the surgeons direct estimation of the steatosis percentage was used (accuracy = 75.5%). The surgeons quality grading correlated with the degree of ld‐MaS and the surgeons steatosis estimate as well as the incidence of poor initial function and primary nonfunction. In conclusion, the precise estimation of steatosis remains challenging even in experienced hands. Liver texture characteristics are more helpful in identifying macrosteatotic organs than the surgeons actual perception of steatosis. These findings are especially important when histological assessment is not available at the donors hospital. Liver Transpl 19:437–449, 2013.

Individualizing liver transplant immunosuppression using a phenotypic personalized medicine platform

Postoperative liver transplant immunosuppression was personalized using a phenotypic, disease mechanism–independent and indication-agnostic approach. Personalizing drug dosing After organ transplant, patients are on a merry-go-round of medicines and procedures to make sure that the graft is not rejected. Currently, physicians use dosing guidelines for drugs meant to suppress the immune system, but also use educated guesses in choosing dose, to account for variability in patient response to the drugs and drug-drug interactions. Now, Zarrinpar and colleagues have come up with a mathematical approach to remove the guesswork. Their approach, called parabolic personalized dosing (PPD), relies on algebraic equations to relate phenotype (in this case, trough level of an immunosuppressant, tacrolimus) to input (tacrolimus concentration). By mapping patient response over the course of treatment, the equation produces a two-dimensional (2D) parabola that indicates the next dose that the patient should receive. The parabola shifts as drugs are added or taken away, or as the patient undergoes additional clinical procedures, such as hemodialysis, which can interfere with drug distribution within the body. The PPD approach was tested in four patients and compared to the standard of care, physician guidance. The PPD patients were out of trough range less frequently and for shorter periods of time than controls, suggesting that the equation was predicting next doses accurately. Future studies will involve more patients and will expand the PPD equation to represent a 3D parabolic surface, which will factor in drug combinations. The PPD approach will have broad applicability beyond transplant medicine, because it is independent of disease mechanism or drug of choice and could thus personalize regimens for many types of patients. Posttransplant immunosuppressive drugs such as tacrolimus have narrow therapeutic ranges. Inter- and intraindividual variability in dosing requirements conventionally use physician-guided titrated drug administration, which results in frequent deviations from the target trough ranges, particularly during the critical postoperative phase. There is a clear need for personalized management of posttransplant regimens to prevent adverse events and allow the patient to be discharged sooner. We have developed the parabolic personalized dosing (PPD) platform, which is a surface represented by a second-order algebraic equation with experimentally determined coefficients of the equation being unique to each patient. PPD uses clinical data, including blood concentrations of tacrolimus—the primary phenotypic readout for immunosuppression efficacy—to calibrate these coefficients and pinpoint the optimal doses that result in the desired patient-specific response. In this pilot randomized controlled trial, we compared four transplant patients prospectively treated with tacrolimus using PPD with four control patients treated according to the standard of care (physician guidance). Using phenotype to personalize tacrolimus dosing, PPD effectively managed patients by keeping tacrolimus blood trough levels within the target ranges. In a retrospective analysis of the control patients, PPD-optimized prednisone and tacrolimus dosing improved tacrolimus trough-level management and minimized the need to recalibrate dosing after regimen changes. PPD is independent of disease mechanism and is agnostic of indication and could therefore apply beyond transplant medicine to dosing for cancer, infectious diseases, and cardiovascular medicine, where patient response is variable and requires careful adjustments through optimized inputs.

TLR4 Signaling via NANOG Cooperates With STAT3 to Activate Twist1 and Promote Formation of Tumor-initiating Stem-like Cells in Livers of Mice.

BACKGROUND & AIMS Obesity and alcohol consumption contribute to steatohepatitis, which increases the risk for hepatitis C virus (HCV)-associated hepatocellular carcinomas (HCCs). Mouse hepatocytes that express HCV-NS5A in liver up-regulate the expression of Toll-like receptor 4 (TLR4), and develop liver tumors containing tumor-initiating stem-like cells (TICs) that express NANOG. We investigated whether the TLR4 signals to NANOG to promote the development of TICs and tumorigenesis in mice placed on a Western diet high in cholesterol and saturated fat (HCFD). METHODS We expressed HCV-NS5A from a transgene (NS5A Tg) in Tlr4-/- (C57Bl6/10ScN), and wild-type control mice. Mice were fed a HCFD for 12 months. TICs were identified and isolated based on being CD133+, CD49f+, and CD45-. We obtained 142 paraffin-embedded sections of different stage HCCs and adjacent nontumor areas from the same patients, and performed gene expression, immunofluorescence, and immunohistochemical analyses. RESULTS A higher proportion of NS5A Tg mice developed liver tumors (39%) than mice that did not express HCV NS5A after the HCFD (6%); only 9% of Tlr4-/- NS5A Tg mice fed HCFD developed liver tumors. Livers from NS5A Tg mice fed the HCFD had increased levels of TLR4, NANOG, phosphorylated signal transducer and activator of transcription (pSTAT3), and TWIST1 proteins, and increases in Tlr4, Nanog, Stat3, and Twist1 messenger RNAs. In TICs from NS5A Tg mice, NANOG and pSTAT3 directly interact to activate expression of Twist1. Levels of TLR4, NANOG, pSTAT3, and TWIST were increased in HCC compared with nontumor tissues from patients. CONCLUSIONS HCFD and HCV-NS5A together stimulated TLR4-NANOG and the leptin receptor (OB-R)-pSTAT3 signaling pathways, resulting in liver tumorigenesis through an exaggerated mesenchymal phenotype with prominent Twist1-expressing TICs.

Liver Transplantation in Recipients Receiving Renal Replacement Therapy: Outcomes Analysis and the Role of Intraoperative Hemodialysis

The Model for End‐Stage Liver Disease (MELD) system has dramatically increased the number of recipients requiring pretransplant renal replacement therapy (RRT) prior to liver transplantation (LT). Factors affecting post‐LT outcomes and the need for intraoperative RRT (IORRT) were analyzed in 500 consecutive recipients receiving pretransplant RRT, including comparisons among recipients not receiving IORRT (No‐IORRT, n = 401), receiving planned IORRT (Pl‐IORRT, n = 70), and receiving emergent, unplanned RRT after LT initiation (Em‐IORRT, n = 29). Despite a median MELD of 39, overall 30‐day, 1‐, 3‐ and 5‐year survivals were 93%, 75%, 68% and 65%, respectively. Em‐IORRT recipients had significantly more intraoperative complications (arrhythmias, postreperfusion syndrome, coagulopathy) compared with both No‐IORRT and Pl‐IORRT and greater 30‐day graft loss (28% vs. 10%, p = 0.004) and need for retransplantation (24% vs. 10%, p = 0.099) compared with No‐IORRT. A risk score based on multivariate predictors of IORRT accurately identified recipients with chronic (sensitivity 84%, specificity 72%, concordance‐statistic [c‐statistic] 0.829) and acute (sensitivity 93%, specificity 61%, c‐statistic 0.776) liver failure requiring IORRT. In this largest experience of LT in recipients receiving RRT, we report excellent survival and propose a practical model that accurately identifies recipients who may benefit from IORRT. For this select group, timely initiation of IORRT reduces intraoperative complications and improves posttransplant outcomes.