Targeted Quantification of Proteoforms in Complex Samples by Proteoform Reaction Monitoring.

Existing mass spectrometric assays used for sensitive and specific measurements of target proteins across multiple samples, such as selected/multiple reaction monitoring (SRM/MRM) or parallel reaction monitoring (PRM), are peptide-based methods for bottom-up proteomics. Here, we describe an approach based on the principle of PRM for the measurement of intact proteoforms by targeted top-down proteomics, termed proteoform reaction monitoring (PfRM). We explore the ability of our method to circumvent traditional limitations of top-down proteomics, such as sensitivity and reproducibility. We also introduce a new software program, Proteoform Finder (part of ProSight Native), specifically designed for the easy analysis of PfRM data. PfRM was initially benchmarked by quantifying three standard proteins. The linearity of the assay was shown over almost 3 orders of magnitude in the femtomole range, with limits of detection and quantification in the low femtomolar range. We later applied our multiplexed PfRM assay to complex samples to quantify biomarker candidates in peripheral blood mononuclear cells (PBMCs) from liver-transplanted patients, suggesting their possible translational applications. These results demonstrate that PfRM has the potential to contribute to the accurate quantification of protein biomarkers for diagnostic purposes and to improve our understanding of disease etiology at the proteoform level.

Donor-derived cell-free DNA levels predict graft injury in liver transplant recipients.

Donor-derived cell-free DNA (dd-cfDNA) has been evaluated as a rejection marker in organ transplantation. This study sought to assess the utility of dd-cfDNA to diagnose graft injury in liver transplant recipients (LTR) and as a predictive biomarker prior to different causes of graft dysfunction. Plasma from single and multicenter LTR cohorts was analyzed for dd-cfDNA. Phenotypes of treated biopsy-proven acute rejection (AR, N = 57), normal function (TX, N = 94), and acute dysfunction no rejection (ADNR; N = 68) were divided into training and test sets. In the training set, dd-cfDNA was significantly different between AR versus TX (AUC 0.95, 5.3% cutoff) and AR versus ADNR (AUC 0.71, 20.4% cutoff). Using these cutoffs in the test set, the accuracy and NPV were 87% and 100% (AR vs. TX) and 66.7% and 87.8% (AR vs. ADNR). Blood samples collected serially from LTR demonstrated incremental elevations in dd-cfDNA prior to the onset of graft dysfunction (AR > ADNR), but not in TX. Dd-cfDNA also decreased following treatment of rejection. In conclusion, the serial elevation of dd-cfDNA identifies pre-clinical graft injury in the context of normal liver function tests and is greatest in rejection. This biomarker may help detect early signs of graft injury and rejection to inform LTR management strategies.

Epigenetic reprogramming of host and viral genes by Human Cytomegalovirus infection in Kasumi-3 myeloid progenitor cells at early times post-infection.

HCMV establishes latency in myeloid cells. Using the Kasumi-3 latency model, we previously showed that lytic gene expression is activated prior to establishment of latency in these cells. The early events in infection may have a critical role in shaping establishment of latency. Here, we have used an integrative multi-omics approach to investigate dynamic changes in host and HCMV gene expression and epigenomes at early times post infection. Our results show dynamic changes in viral gene expression and viral chromatin. Analyses of Pol II, H3K27Ac and H3K27me3 occupancy of the viral genome showed that 1) Pol II occupancy was highest at the MIEP at 4 hours post infection. However, it was observed throughout the genome; 2) At 24 hours, H3K27Ac was localized to the major immediate early promoter/enhancer and to a possible second enhancer in the origin of replication OriLyt; 3) viral chromatin was broadly accessible at 24 hpi. In addition, although HCMV infection activated expression of some host genes, we observed an overall loss of de novo transcription. This was associated with loss of promoter-proximal Pol II and H3K27Ac, but not with changes in chromatin accessibility or a switch in modification of H3K27.Importance.HCMV is an important human pathogen in immunocompromised hosts and developing fetuses. Current anti-viral therapies are limited by toxicity and emergence of resistant strains. Our studies highlight emerging concepts that challenge current paradigms of regulation of HCMV gene expression in myeloid cells. In addition, our studies show that HCMV has a profound effect on de novo transcription and the cellular epigenome. These results may have implications for mechanisms of viral pathogenesis.

Acute murine cytomegalovirus disrupts established transplantation tolerance and causes recipient allo-sensitization.

We have previously shown that acute cytomegalovirus (CMV) infection disrupts the induction of transplantation tolerance. However, what impact acute CMV infection would have on the maintenance of established tolerance and on subsequent recipient allo-sensitization is a clinically important unanswered question. Here we used an allogeneic murine islet transplantation tolerance model to examine the impact of acute CMV infection on: (a) disruption of established transplantation tolerance during tolerance maintenance; and (b) the possibility of recipient allo-sensitization by CMV-mediated disruption of stable tolerance. We demonstrated that acute CMV infection abrogated transplantation tolerance during the maintenance stage in 50%-60% recipients. We further demonstrated that acute CMV infection-mediated tolerance disruption led to recipient allo-sensitization by reverting the tolerant state of allo-specific T cells and promoting their differentiation to allo-specific memory cells. Consequently, a second same-donor islet allograft was rejected in an accelerated fashion by these recipients. Our study therefore supports close monitoring for allo-sensitization in previously tolerant transplant recipients in whom tolerance maintenance is disrupted by an episode of acute CMV infection.

Discovery and Validation of a Biomarker Model (PRESERVE) Predictive of Renal Outcomes After Liver Transplantation.

BACKGROUND AND AIMS: A high proportion of patients develop chronic kidney disease (CKD) after liver transplantation (LT). We aimed to develop clinical/protein models to predict future glomerular filtration rate (GFR) deterioration in this population. APPROACH AND RESULTS: In independent multicenter discovery (CTOT14) and single-center validation (BUMC) cohorts, we analyzed kidney injury proteins in serum/plasma samples at month 3 after LT in recipients with preserved GFR who demonstrated subsequent GFR deterioration versus preservation by year 1 and year 5 in the BUMC cohort. In CTOT14, we also examined correlations between serial protein levels and GFR over the first year. A month 3 predictive model was constructed from clinical and protein level variables using the CTOT14 cohort (n = 60). Levels of ß-2 microglobulin and CD40 antigen and presence of hepatitis C virus (HCV) infection predicted early (year 1) GFR deterioration (area under the curve [AUC], 0.814). We observed excellent validation of this model (AUC, 0.801) in the BUMC cohort (n = 50) who had both early and late (year 5) GFR deterioration. At an optimal threshold, the model had the following performance characteristics in CTOT14 and BUMC, respectively: accuracy (0.75, 0.8), sensitivity (0.71, 0.67), specificity (0.78, 0.88), positive predictive value (0.74, 0.75), and negative predictive value (0.76, 0.82). In the serial CTOT14 analysis, several proteins, including ß-2 microglobulin and CD40, correlated with GFR changes over the first year. CONCLUSIONS: We have validated a clinical/protein model (PRESERVE) that early after LT can predict future renal deterioration versus preservation with high accuracy. This model may help select recipients at higher risk for subsequent CKD for early, proactive renal sparing strategies.

Murine cytomegalovirus dissemination but not reactivation in donor-positive/recipient-negative allogeneic kidney transplantation can be effectively prevented by transplant immune tolerance.

Cytomegalovirus (CMV) reactivation from latently infected donor organs post-transplantation and its dissemination cause significant comorbidities in transplant recipients. Transplant-induced inflammation combined with chronic immunosuppression has been thought to provoke CMV reactivation and dissemination, although sequential events in this process have not been studied. Here, we investigated this process in a high-risk donor CMV-positive to recipient CMV-negative allogeneic murine kidney transplantation model. Recipients were either treated with indefinite immunosuppression or tolerized in a donor-specific manner. Untreated recipients served as controls. Kidney allografts from both immunosuppressed and tolerized recipients showed minimal alloimmunity-mediated graft inflammation and normal function for up to day 60 post-transplantation. However, despite the absence of such inflammation in the immunosuppressed and tolerized groups, CMV reactivation in the donor positive kidney allograft was readily observed. Interestingly, subsequent CMV replication and dissemination to distant organs only occurred in immunosuppressed recipients in which CMV-specific CD8 T cells were functionally impaired; whereas in tolerized recipients, host anti-viral immunity was well-preserved and CMV dissemination was effectively prevented. Thus, our studies uncoupled CMV reactivation from its dissemination, and underscore the potential role of robust transplantation tolerance in preventing CMV diseases following allogeneic kidney transplantation.

Kidney-intrinsic factors determine the severity of ischemia/reperfusion injury in a mouse model of delayed graft function.

Delayed graft function due to transplant ischemia/reperfusion injury adversely affects up to 50% of deceased-donor kidney transplant recipients. However, key factors contributing to the severity of ischemia/reperfusion injury remain unclear. Here, using a clinically relevant mouse model of delayed graft function, we demonstrated that donor genetic background and kidney-intrinsic MyD88/Trif-dependent innate immunity were key determinants of delayed graft function. Functional deterioration of kidney grafts directly corresponded with the duration of cold ischemia time. The graft dysfunction became irreversible after cold ischemia time exceeded six hours. When cold ischemia time reached four hours, kidney grafts displayed histological features reflective of delayed graft function seen in clinical kidney transplantation. Notably, kidneys of B6 mice exhibited significantly more severe histological and functional impairment than kidneys of C3H or BALB/c mice, regardless of recipient strains or alloreactivities. Furthermore, allografts of B6 mice also showed an upregulation of IL-6, neutrophil gelatinase-associated lipocalin, and endoplasmic reticulum stress genes, as well as an increased influx of host neutrophils and memory CD8 T-cells. In contrast, donor MyD88/Trif deficiency inhibited neutrophil influx and decreased the expression of IL-6 and endoplasmic reticulum stress genes, along with improved graft function and prolonged allograft survival. Thus, kidney-intrinsic factors involving genetic characteristics and innate immunity serve as critical determinants of the severity of delayed graft function. This preclinical murine model allows for further investigations of the mechanisms underlying delayed graft function.

Discovery and validation of a novel blood-based molecular biomarker of rejection following liver transplantation.

Noninvasive biomarker profiles of acute rejection (AR) could affect the management of liver transplant (LT) recipients. Peripheral blood was collected following LT for discovery (Northwestern University [NU]) and validation (National Institute of Allergy and Infectious Diseases Clinical Trials in Organ Transplantation [CTOT]-14 study). Blood gene profiling was paired with biopsies showing AR or ADNR (acute dysfunction no rejection) as well as stable graft function samples (Transplant eXcellent-TX). CTOT-14 subjects had serial collections prior to AR, ADNR, TX, and after AR treatment. NU cohort gene expression (46 AR, 45 TX) was analyzed using random forest models to generate a classifier training set (36 gene probe) distinguishing AR vs TX (area under the curve 0.92). The algorithm and threshold were locked and tested on the CTOT-14 validation cohort (14 AR, 50 TX), yielding an accuracy of 0.77, sensitivity 0.57, specificity 0.82, positive predictive value (PPV) 0.47, and negative predictive value (NPV) 0.87 for AR vs TX. The probability score line slopes were positive preceding AR, and negative preceding TX and non-AR (TX + ADNR) (P ≤ .001) and following AR treatment. In conclusion, we have developed a blood biomarker diagnostic for AR that can be detected prior to AR-associated graft injury as well a normal graft function (non-AR). Further studies are needed to evaluate its utility in precision-guided immunosuppression optimization following LT.

Use of biomarkers to improve immunosuppressive drug development and outcomes in renal organ transplantation: A meeting report.

On September 27-28, 2018 the Food and Drug Administration (FDA) and the Critical Path Institute's Transplant Therapeutics Consortium convened a public workshop titled "Evidence-Based Treatment Decisions in Transplantation: The Right Dose & Regimen for the Right Patient/Individualized Treatment." The workshop facilitated cooperative engagement of transplant community stakeholders, including pharmaceutical industry, academic researchers, clinicians, patients, and regulators to discuss methods to advance the development of novel immunosuppressive drugs for use in solid organ transplantation. Day 1 focused on the utility of biomarkers in drug development, with considerations for seeking regulatory endorsement for use in clinical trials. Biomarkers add value to drug development by improving patient selection criteria, safety monitoring, endpoint selection, and more. Regulatory endorsement through the FDA Biomarker Qualification Program encourages the use of biomarkers in drug development by instilling confidence and consistency in biomarker interpretation across trials. Public-private partnerships or consortia allow stakeholders to share expertise, resources, and data in pursuit of biomarker qualification. Biomarkers relevant to pretransplant risk assessment, early posttransplant care, and assessment of immune response, immunosuppressive drug efficacy, and graft function as discussed on day 1 of the workshop are described.

External Validation of a Pretransplant Biomarker Model (REVERSE) Predictive of Renal Recovery After Liver Transplantation.

In patients with end-stage liver disease, the ability to predict recovery of renal function following liver transplantation (LT) remains elusive. However, several important clinical decisions depend on whether renal dysfunction is recoverable after LT. We used a cohort of patients undergoing LT to independently validate a published pre-LT model predictive of post-transplant renal recovery (Renal Recovery Assessment at Liver Transplant [REVERSE]: high osteopontin [OPN] and tissue inhibitor of metalloproteinases-1 [TIMP-1] levels, age < 57, no diabetes). Serum samples pre-LT and 4-12 weeks post-LT (n = 117) were analyzed for kidney injury proteins from three groups of recipients: (1) estimated glomerular filtration rate (eGFR) < 30 mL/minute/1.73 m2 prior to and after LT (irreversible acute kidney injury [AKI]), (2) eGFR < 30 mL/minute/1.73 m2 prior to LT and >50 mL/minute/1.73 m2 after LT (reversible AKI [rAKI]) (3) eGFR > 50 mL/minute/1.73 m2 prior to and after LT (no AKI). In patients with elevated pre-LT serum levels of OPN and TIMP-1, recovery of renal function correlated with decreases in the level of both proteins. At 4 weeks post-LT (n = 77 subset), the largest decline in OPN and TIMP-1 was seen in the rAKI group. Validation of the REVERSE model in this independent data set had high area under the curve (0.78) in predicting full post-LT renal recovery (sensitivity 0.86, specificity 0.6, positive predictive value 0.81, negative predictive value 0.69). Our eGFR findings were confirmed using measured GFR. Conclusion: The REVERSE model, derived from an initial training set combining plasma biomarkers and clinical characteristics, demonstrated excellent external validation performance characteristics in an independent patient cohort using serum samples. Among patients with kidney injury pre-LT, the predictive ability of this model may prove beneficial in clinical decision-making both prior to and following transplantation.

Percutaneous Access of the Modified Hutson Loop for Retrograde Cholangiography, Endoscopy, and Biliary Interventions.

PURPOSE: The purpose of this study was to present the institutional experience of performing endoscopy, cholangiography, and biliary interventions through the modified Hutson loop by interventional radiology. MATERIALS AND METHODS: A total of 61 of 64 modified Hutson loop access procedures were successful. This single-center retrospective study included 61 successful procedures of biliary interventions using existing modified Hutson loops (surgically affixed subcutaneous jejunal limb adjacent to biliary anastomosis or anastomoses) for diagnostic or therapeutic purposes in 21 patients. Seventeen of 21 patients (81%) had undergone liver transplantation. Indications included biliary strictures (n = 18) and biliary leaks (n = 3). The clinical success and complications were evaluated. RESULTS: There were 3 of 26 modified Hutson loop retrograde biliary intervention failures (12%) before introduction of endoscopy and no failures (0 of 38 [0%]) subsequently (P = .06). Endoscopy or cholangioscopy was performed in 19 procedures by interventional radiologists. Retrograde biliary interventions included diagnostic cholangiography (n = 26), cholangioplasty (n = 25), stent placement (n = 29), stent retrieval (n = 25), and biliary drainage catheter placement (n = 5). No procedure-related mortality occurred. There was 1 major complication (duodenal perforation) (1.6%) and 12 minor complications (19%). In the 9 patients undergoing therapeutic interventions for biliary strictures, there was a significant decrease in median alkaline phosphatase (288.5 to 174.5 U/L; P = .03). There was a trend toward decrease in median bilirubin levels (1.7 to 1 mg/dL; P = .06) at 1 month post-intervention. CONCLUSIONS: The modified Hutson loop provided interventional radiologists a safe and effective alternative access to manage biliary complications in patients with biliary-enteric anastomoses. Introduction of the endoscope in interventional radiology has improved the success rate of these procedures.

Correction to: Trends and predictors of multidimensional health-related quality of life after living donor kidney transplantation.

In its original publication, an erroneous version of Fig. 2d was included in the manuscript. The corrected figure has now been added.

Trends and predictors of multidimensional health-related quality of life after living donor kidney transplantation.

PURPOSE: Living donor kidney transplant (LDKT) imparts the best graft and patient survival for most end-stage kidney disease (ESKD) patients. Yet, there remains variation in post-LDKT health-related quality of life (HRQOL). Improved understanding of post-LDKT HRQOL can help identify patients for interventions to maximize the benefit of LDKT. METHODS: For 477 LDKT recipients transplanted between 11/2007 and 08/2016, we assessed physical, mental, social, and kidney-targeted HRQOL pre-LDKT, as well as 3 and 12 months post-operatively using the SF-36, Kidney Disease Quality of Life-Short Form (KDQOL-SF), and the Functional Assessment of Cancer Therapy-Kidney Symptom Index 19 item version (FKSI-19). We then examined trajectories of each HRQOL domain using latent growth curve models (LGCMs). We also examined associations between decline in HRQOL from 3 months to 12 months post-LDKT and death censored graft failure (DCGF) using Cox regression. RESULTS: Large magnitude effects (d > 0.80) were observed from pre- to post-LDKT change on the SF-36 Vitality scale (d = 0.81) and the KDQOL-SF Burden of Kidney Disease (d = 1.05). Older age and smaller pre- to post-LDKT decreases in serum creatinine were associated with smaller improvements on many HRQOL scales across all domains in LGCMs. Higher DCGF rates were associated with worse physical [e.g., SF-36 PCSoblique hazard ratio (HR) 1.18; 95% CI 1.01-1.38], mental (KDQOL-SF Cognitive Function HR 1.27; 95% CI 1.00-1.62), and kidney-targeted (FKSI-19 HR: 1.18; 95% CI 1.00-1.38) HRQOL domains. CONCLUSION: Clinical HRQOL monitoring may help identify patients who are most likely to have failing grafts and who would benefit from post-LDKT intervention.

A clinically relevant murine model unmasks a "two-hit" mechanism for reactivation and dissemination of cytomegalovirus after kidney transplant.

Reactivation of latent cytomegalovirus remains an important complication after transplant. Although immunosuppression (IS) has been implicated as a primary cause, we have previously shown that the implantation response of a kidney allograft can lead to early transcriptional activation of latent murine cytomegalovirus (MCMV) genes in an immune-competent host and to MCMV reactivation and dissemination to other organs in a genetically immune-deficient recipient. We now describe a model that allows us to separately analyze the impact of the implantation effect vs that of a clinically relevant IS regimen. Treatment with IS of latently infected mice alone does not induce viral reactivation, but transplant of latently infected allogeneic kidneys combined with IS facilitates MCMV reactivation in the graft and dissemination to other organs. The IS regimen effectively dampens allo-immune inflammatory pathways and depletes recipient anti-MCMV but does not affect ischemia-reperfusion injury pathways. MCMV reactivation similar to that seen in allogeneic transplants combined with also occurs after syngeneic transplants. Thus, our data strongly suggest that while ischemia-reperfusion injury of the implanted graft is sufficient and necessary to initiate transcriptional reactivation of latent MCMV ("first hit"), IS is permissive to the first hit and facilitates dissemination to other organs ("second hit").

Development and clinical validity of a novel blood-based molecular biomarker for subclinical acute rejection following kidney transplant.

Noninvasive biomarkers are needed to monitor stable patients after kidney transplant (KT), because subclinical acute rejection (subAR), currently detectable only with surveillance biopsies, can lead to chronic rejection and graft loss. We conducted a multicenter study to develop a blood-based molecular biomarker for subAR using peripheral blood paired with surveillance biopsies and strict clinical phenotyping algorithms for discovery and validation. At a predefined threshold, 72% to 75% of KT recipients achieved a negative biomarker test correlating with the absence of subAR (negative predictive value: 78%-88%), while a positive test was obtained in 25% to 28% correlating with the presence of subAR (positive predictive value: 47%-61%). The clinical phenotype and biomarker independently and statistically correlated with a composite clinical endpoint (renal function, biopsy-proved acute rejection, ≥grade 2 interstitial fibrosis, and tubular atrophy), as well as with de novo donor-specific antibodies. We also found that <50% showed histologic improvement of subAR on follow-up biopsies despite treatment and that the biomarker could predict this outcome. Our data suggest that a blood-based biomarker that reduces the need for the indiscriminate use of invasive surveillance biopsies and that correlates with transplant outcomes could be used to monitor KT recipients with stable renal function, including after treatment for subAR, potentially improving KT outcomes.

A novel murine model of differentiation-mediated cytomegalovirus reactivation from latently infected bone marrow haematopoietic cells.

CD34+ myeloid lineage progenitor cells are an important reservoir of latent human cytomegalovirus (HCMV), and differentiation to macrophages or dendritic cells (DCs) is known to cause reactivation of latent virus. Due to its species-specificity, murine models have been used to study mouse CMV (MCMV) latency and reactivation in vivo. While previous studies have shown that MCMV genomic DNA can be detected in the bone marrow (BM) of latently infected mice, the identity of these cells has not been defined. Therefore, we sought to identify and enrich for cellular sites of MCMV latency in the BM haematopoietic system, and to explore the potential for establishing an in vitro model for reactivation of latent MCMV. We studied the kinetics and cellular characteristics of acute infection and establishment of latency in the BM of mice. We found that while MCMV can infect a broad range of haematopoietic BM cells (BMCs), latent virus is only detectable in haematopoietic stem cells (HSCs), myeloid progenitor cells, monocytes and DC-enriched cell subsets. Using three separate approaches, MCMV reactivation was detected in association with differentiation into DC-enriched BMCs cultured in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 4 (IL-4) followed by lipopolysaccharide (LPS) treatment. In summary, we have defined the kinetics and cellular profile of MCMV infection followed by the natural establishment of latency in vivo in the mouse BM haematopoietic system, including the haematopoietic phenotypes of cells that are permissive to acute infection, establish and harbour detectable latent virus, and can be stimulated to reactivate following DC enrichment and differentiation, followed by treatment with LPS.

Institutional decision to adopt Y90 as primary treatment for hepatocellular carcinoma informed by a 1,000-patient 15-year experience.

Yttrium-90 transarterial radioembolization (TARE) is a locoregional therapy (LRT) for hepatocellular carcinoma (HCC). In this study, we present overall survival (OS) outcomes in a 1,000-patient cohort acquired over a 15-year period. Between December 1, 2003 and March 31, 2017, 1,000 patients with HCC were treated with TARE as part of a prospective cohort study. A comprehensive review of toxicity and survival outcomes was performed. Outcomes were stratified by baseline Child-Pugh (CP) class, United Network for Organ Sharing (UNOS), and Barcelona Clinic Liver Cancer (BCLC) staging systems. Albumin and bilirubin laboratory toxicities were compared to baseline. OS outcomes were reported using censoring and intention-to-treat methodologies. All treatments were outpatient, with a median one treatment per patient. Five hundred six (51%) were CP A, 450 (45%) CP B, and 44 (4%) CP C. Two hundred sixty-three (26%) patients were BCLC A, 152 (15%) B, 541 (54%) C, and 44 (4%) D. Three hundred sixty-eight (37%) were UNOS T1/T2, 169 (17%) T3, 147 (15%) T4a, 223 (22%) T4b, and 93 (9%) N/M. In CP A patients, censored OS for BCLC A was 47.3 (confidence interval [CI], 39.5-80.3) months, BCLC B 25.0 (CI, 17.3-30.5) months, and BCLC C 15.0 (CI, 13.8-17.7) months. In CP B patients, censored OS for BCLC A was 27 (CI, 21-30.2) months, BCLC B 15.0 (CI, 12.3-19.0) months, and BCLC C 8.0 (CI, 6.8-9.5) months. Forty-nine (5%) and 110 (11%) patients developed grade 3/4 albumin and bilirubin toxicities, respectively. CONCLUSION: Based on our experience with 1,000 patients over 15 years, we have made a decision to adopt TARE as the first-line transarterial LRT for patients with HCC. Our decision was informed by prospective data and incrementally reported demonstrating outcomes stratified by BCLC, applied as either neoadjuvant or definitive treatment. (Hepatology 2017).

Radiation Segmentectomy: Potential Curative Therapy for Early Hepatocellular Carcinoma.

Purpose To report long-term outcomes of radiation segmentectomy (RS) for early hepatocellular carcinoma (HCC). The authors hypothesized that outcomes are comparable to curative treatments for patients with solitary HCC less than or equal to 5 cm and preserved liver function. Materials and Methods This retrospective study included 70 patients (median age, 71 years; range, 22-96 years) with solitary HCC less than or equal to 5 cm not amenable to percutaneous ablation who underwent RS (dose of >190 Gy) between 2003 and 2016. Patients who underwent subsequent curative liver transplantation were excluded to eliminate this confounding variable affecting survival. Radiologic response of time to progression and median overall survival were estimated by using the Kaplan-Meier method per the guidelines of the European Association for the Study of the Liver (EASL) and the World Health Organization (WHO). Results Seventy patients were treated with RS over 14 years. Sixty-three patients (90%) showed response by using EASL criteria, of which 41 (59%) showed complete response. Fifty patients (71%) achieved response by using WHO criteria, of which 11 (16%) achieved complete response. Response rates at 6 months were 86% and 49% by using EASL and WHO criteria, respectively. Median time to progression was 2.4 years (95% confidence interval: 2.1, 5.7), with 72% of patients having no target lesion progression at 5 years. Median overall survival was 6.7 years (95% confidence interval: 3.1, 6.7); survival probability at 1, 3, and 5 years was 98%, 66%, and 57%, respectively. Overall survival probability at 1, 3, and 5 years was 100%, 82%, and 75%, respectively, in patients with baseline tumor size less than or equal to 3 cm (n = 45) and was significantly longer than in patients with tumors greater than 3 cm (P = .026). Conclusion RS provides response rates, tumor control, and survival outcomes comparable to curative-intent treatments for selected patients with early-stage HCC who have preserved liver function. © RSNA, 2018 Online supplemental material is available for this article.

A point-based prediction model for cardiovascular risk in orthotopic liver transplantation: The CAR-OLT score.

Cardiovascular disease (CVD) complications are important causes of morbidity and mortality after orthotopic liver transplantation (OLT). There is currently no preoperative risk-assessment tool that allows physicians to estimate the risk for CVD events following OLT. We sought to develop a point-based prediction model (risk score) for CVD complications after OLT, the Cardiovascular Risk in Orthotopic Liver Transplantation risk score, among a cohort of 1,024 consecutive patients aged 18-75 years who underwent first OLT in a tertiary-care teaching hospital (2002-2011). The main outcome measures were major 1-year CVD complications, defined as death from a CVD cause or hospitalization for a major CVD event (myocardial infarction, revascularization, heart failure, atrial fibrillation, cardiac arrest, pulmonary embolism, and/or stroke). The bootstrap method yielded bias-corrected 95% confidence intervals for the regression coefficients of the final model. Among 1,024 first OLT recipients, major CVD complications occurred in 329 (32.1%). Variables selected for inclusion in the model (using model optimization strategies) included preoperative recipient age, sex, race, employment status, education status, history of hepatocellular carcinoma, diabetes, heart failure, atrial fibrillation, pulmonary or systemic hypertension, and respiratory failure. The discriminative performance of the point-based score (C statistic = 0.78, bias-corrected C statistic = 0.77) was superior to other published risk models for postoperative CVD morbidity and mortality, and it had appropriate calibration (Hosmer-Lemeshow P = 0.33). CONCLUSION: The point-based risk score can identify patients at risk for CVD complications after OLT surgery (available at www.carolt.us); this score may be useful for identification of candidates for further risk stratification or other management strategies to improve CVD outcomes after OLT. (Hepatology 2017;66:1968-1979).

Outcomes of Surgical Resection after Radioembolization for Hepatocellular Carcinoma.

PURPOSE: To longitudinally study clinical and radiologic outcomes of patients with hepatocellular carcinoma (HCC) who underwent yttrium-90 transarterial radioembolization (TARE) as a bridge to surgical resection. MATERIALS AND METHODS: TARE was performed in 31 patients with HCC before resection. Of patients, 25 underwent major hepatic resection (16 received right hepatectomy and 9 received trisegmentectomy), and 6 underwent partial hepatectomy. Clinical outcomes after TARE and after resection were recorded. Future liver remnant (FLR) was calculated before and after TARE, and actual liver remnant volume was calculated after resection. Radiologic response after TARE and pathologic necrosis were assessed. Overall and recurrence-free survivals after resection were estimated. RESULTS: Median time between TARE and resection was 2.9 months (interquartile range [IQR]: 2-5 months). Median FLR hypertrophy after TARE (and before resection) was 23.3% (IQR:10%-48%) for patients who had radiation lobectomy and 9% (IQR: 6%-25%) for patients who had radiation segmentectomy (P = .037). Median augmented hypertrophy of the liver remnant 3 months after resection was 72% (IQR:45%-88%) in patients who had radiation lobectomy and 94% (IQR: 72%-146%) in patients who had radiation segmentectomy. Complete, 50%-99%, and < 50% pathologic tumor necrosis was identified in 14 (45%), 10 (32%), and 7 (23%) tumors. Disease control was achieved in all 31 patients. Survival rates at 1 and 3 years were 96% and 86%, respectively. Median recurrence-free survival was 34.2 months (95% confidence interval,18.7-34.2). CONCLUSIONS: TARE can serve as a safe bridge to resection providing FLR hypertrophy and disease control.