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Dive into the research topics where Johnny C. Hong is active.

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Featured researches published by Johnny C. Hong.


Gastroenterology | 2012

Efficacy of neoadjuvant chemoradiation, followed by liver transplantation, for perihilar cholangiocarcinoma at 12 US centers.

Sarwa Darwish Murad; W. Ray Kim; Denise M. Harnois; David D. Douglas; James R. Burton; Laura Kulik; Jean F. Botha; Joshua D. Mezrich; William C. Chapman; Jason J. Schwartz; Johnny C. Hong; Jean C. Emond; Hoonbae Jeon; Charles B. Rosen; Gregory J. Gores; Julie K. Heimbach

BACKGROUND & AIMS Excellent single-center outcomes of neoadjuvant chemoradiation and liver transplantation for unresectable perihilar cholangiocarcinoma caused the United Network of Organ Sharing to offer a standardized model of end-stage liver disease (MELD) exception for this disease. We analyzed data from multiple centers to determine the effectiveness of this treatment and the appropriateness of the MELD exception. METHODS We collected and analyzed data from 12 large-volume transplant centers in the United States. These centers met the inclusion criteria of treating 3 or more patients with perihilar cholangiocarcinoma using neoadjuvant therapy, followed by liver transplantation, from 1993 to 2010 (n = 287 total patients). Center-specific protocols and medical charts were reviewed on-site. RESULTS The patients completed external radiation (99%), brachytherapy (75%), radiosensitizing therapy (98%), and/or maintenance chemotherapy (65%). Seventy-one patients dropped out before liver transplantation (rate, 11.5% in 3 months). Intent-to-treat survival rates were 68% and 53%, 2 and 5 years after therapy, respectively; post-transplant, recurrence-free survival rates were 78% and 65%, respectively. Patients outside the United Network of Organ Sharing criteria (those with tumor mass >3 cm, transperitoneal tumor biopsy, or metastatic disease) or with a prior malignancy had significantly shorter survival times (P < .001). There were no differences in outcomes among patients based on differences in surgical staging or brachytherapy. Although most patients came from 1 center (n = 193), the other 11 centers had similar survival times after therapy. CONCLUSIONS Patients with perihilar cholangiocarcinoma who were treated with neoadjuvant therapy followed up by liver transplantation at 12 US centers had a 65% rate of recurrence-free survival after 5 years, showing this therapy to be highly effective. An 11.5% drop-out rate after 3.5 months of therapy indicates the appropriateness of the MELD exception. Rigorous selection is important for the continued success of this treatment.


Annals of Surgery | 2006

Optimal Utilization of Donor Grafts With Extended Criteria: A Single-Center Experience in Over 1000 Liver Transplants

Andrew M. Cameron; R. Mark Ghobrial; Hasan Yersiz; Douglas G. Farmer; Gerald S. Lipshutz; Sherilyn A. Gordon; Michael A. Zimmerman; Johnny C. Hong; Thomas E. Collins; Jeffery Gornbein; Farin Amersi; Michael J. Weaver; Carlos Cao; Tony Chen; Jonathan R. Hiatt; Ronald W. Busuttil

Objective:Severely limited organ resources mandate maximum utilization of donor allografts for orthotopic liver transplantation (OLT). This work aimed to identify factors that impact survival outcomes for extended criteria donors (ECD) and developed an ECD scoring system to facilitate graft-recipient matching and optimize utilization of ECDs. Methods:Retrospective analysis of over 1000 primary adult OLTs at UCLA. Extended criteria (EC) considered included donor age (>55 years), donor hospital stay (>5 days), cold ischemia time (>10 hours), and warm ischemia time (>40 minutes). One point was assigned for each extended criterion. Cox proportional hazard regression model was used for multivariate analysis. Results:Of 1153 allografts considered in the study, 568 organs exhibited no extended criteria (0 score), while 429, 135 and 21 donor allografts exhibited an EC score of 1, 2 and 3, respectively. Overall 1-year patient survival rates were 88%, 82%, 77% and 48% for recipients with EC scores of 0, 1, 2 and 3 respectively (P < 0.001). Adjusting for recipient age and urgency at the time of transplantation, multivariate analysis identified an ascending mortality risk ratio of 1.4 and 1.8 compared to a score of 0 for an EC score of 1, and 2 (P < 0.01) respectively. In contrast, an EC score of 3 was associated with a mortality risk ratio of 4.5 (P < 0.001). Further, advanced recipient age linearly increased the death hazard ratio, while an urgent recipient status increased the risk ratio of death by 50%. Conclusions:Extended criteria donors can be scored using readily available parameters. Optimizing perioperative variables and matching ECD allografts to appropriately selected recipients are crucial to maintain acceptable outcomes and represent a preferable alternative to both high waiting list mortality and to a potentially futile transplant that utilizes an ECD for a critically ill recipient.


Nature Reviews Gastroenterology & Hepatology | 2013

Ischaemia–reperfusion injury in liver transplantation—from bench to bedside

Yuan Zhai; Henrik Petrowsky; Johnny C. Hong; Ronald W. Busuttil; Jerzy W. Kupiec-Weglinski

Ischaemia–reperfusion injury (IRI) in the liver, a major complication of haemorrhagic shock, resection and transplantation, is a dynamic process that involves the two interrelated phases of local ischaemic insult and inflammation-mediated reperfusion injury. This Review highlights the latest mechanistic insights into innate–adaptive immune crosstalk and cell activation cascades that lead to inflammation-mediated injury in livers stressed by ischaemia–reperfusion, discusses progress in large animal experiments and examines efforts to minimize liver IRI in patients who have received a liver transplant. The interlinked signalling pathways in multiple hepatic cell types, the IRI kinetics and positive versus negative regulatory loops at the innate–adaptive immune interface are discussed. The current gaps in our knowledge and the pathophysiology aspects of IRI in which basic and translational research is still required are stressed. An improved appreciation of cellular immune events that trigger and sustain local inflammatory responses, which are ultimately responsible for organ injury, is fundamental to developing innovative strategies for treating patients who have received a liver transplant and developed ischaemia–reperfusion inflammation and organ dysfunction.


Archives of Surgery | 2008

Recurrence of Hepatocellular Carcinoma Following Liver Transplantation A Review of Preoperative and Postoperative Prognostic Indicators

Michael A. Zimmerman; R. Mark Ghobrial; Myron J. Tong; Jonathan R. Hiatt; Andrew M. Cameron; Johnny C. Hong; Ronald W. Busuttil

OBJECTIVE To review the preoperative and postoperative variables that predict hepatocellular carcinoma (HCC) recurrence following orthotopic liver transplantation (OLT). DATA SOURCES A collective review of the literature was conducted by searching the MEDLINE database using several key words: hepatocellular carcinoma, recurrence, liver transplantation, and salvage transplantation. STUDY SELECTION Reviews and original articles containing basic scientific observations and long-term clinical outcomes were included. DATA EXTRACTION Critical observations from peer-reviewed sources were incorporated in this review. DATA SYNTHESIS Overall, 11 studies were reviewed to determine the incidence of HCC recurrence following OLT and to identify prognostic variables of recurrence. Four studies were evaluated to determine the efficacy of salvage transplantation following liver resection. CONCLUSIONS Liver transplantation is a viable treatment option for select patients with HCC and end-stage liver disease. However, in approximately 20% of patients, recurrent HCC is the rate-limiting factor for long-term survival. Despite identification of clinical parameters that may stratify patients at high risk and exhaustive preoperative staging, cancer recurrence is likely the result of microscopic extrahepatic disease. With a desperate donor organ shortage, locoregional ablation techniques and resection are being employed in patients on the waiting list to serve as a bridge to OLT. Furthermore, some have advocated aggressive surgical resection of isolated metastasis in both the liver and extrahepatic viscera. Whether these creative strategies confer a survival advantage is unknown; it will require long-term follow-up to determine their efficacy.


Transplantation | 2000

Sirolimus-induced thrombocytopenia and leukopenia in renal transplant recipients: risk factors, incidence, progression, and management.

Johnny C. Hong; Barry D. Kahan

BACKGROUND Our study assessed the factors that predispose renal transplant recipients to the occurrence of thrombocytopenia and leukopenia, as well as the severity and the time- and concentration-dependence of these side-effects, after administration of sirolimus (SRL) in combination with a cyclosporine (CsA) and prednisone (Pred) regimen. METHODS The clinical courses of two cohorts of renal transplant recipients were compared over 1 year: 119 patients received SRL in addition to CsA and Pred, and 65 demographically similar, concurrent patients received only CsA and Pred. Using an analysis of variance, pretransplant laboratory values and SRL trough concentrations (C0) were correlated with the occurrence, severity, and persistence of drug-induced thrombocytopenia (platelet count <150x10(3) cell/mm3) and/or leukopenia (white blood cell count <5,000/mm3). RESULTS Neither the ethnic background nor the pretransplant cytomegalovirus serological status was associated with the occurrence of hematological complications. Thrombocytopenia was usually observed during the first 4 weeks of treatment (P=0.004). The occurrence, but not the severity or the persistence, of both thrombocytopenia and leukopenia correlated significantly with SRL trough concentrations > or =16 ng/ml (P=0.001 and 0.0001, respectively). A significant correlation is evident between the occurrence of the two adverse effects (P=0.001). In 89% of patients, the first episode of either type of cytopenia resolved spontaneously. Among the remaining 11%, 7% responded to SRL dose reduction, and 4% to temporary suspension. No patient required permanent cessation of SRL therapy. Most patients experienced repeated, but self-limited, episodes of toxicity. CONCLUSION Thrombocytopenia and leukopenia are not infrequent occurrences with SRL treatment, and they generally resolve spontaneously.


American Journal of Transplantation | 2012

Simultaneous Liver-Kidney Transplantation Summit: Current State and Future Directions

Mitra K. Nadim; Randall S. Sung; Connie L. Davis; Kenneth A. Andreoni; Scott W. Biggins; Gabriel M. Danovitch; Sandy Feng; John J. Friedewald; Johnny C. Hong; John A. Kellum; W. R. Kim; John R. Lake; Larry Melton; Elizabeth A. Pomfret; Sammy Saab; Yuri Genyk

Although previous consensus recommendations have helped define patients who would benefit from simultaneous liver–kidney transplantation (SLK), there is a current need to reassess published guidelines for SLK because of continuing increase in proportion of liver transplant candidates with renal dysfunction and ongoing donor organ shortage. The purpose of this consensus meeting was to critically evaluate published and registry data regarding patient and renal outcomes following liver transplantation alone or SLK in liver transplant recipients with renal dysfunction. Modifications to the current guidelines for SLK and a research agenda were proposed.


Annals of Surgery | 2012

Liver transplantation for nonalcoholic steatohepatitis: the new epidemic.

Vatche G. Agopian; Fady M. Kaldas; Johnny C. Hong; Whittaker M; Curtis Holt; Abbas Rana; Ali Zarrinpar; Henrik Petrowsky; Douglas G. Farmer; Hasan Yersiz; Xia; Hiatt; R. W. Busuttil

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.


Annals of Surgery | 2013

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

Vatche G. Agopian; Henrik Petrowsky; Fady M. Kaldas; Ali Zarrinpar; Douglas G. Farmer; Hasan Yersiz; Curtis Holt; Michael P. Harlander-Locke; Johnny C. Hong; Abbas Rana; Robert S. Venick; Sue V. McDiarmid; Leonard I. Goldstein; Francisco Durazo; Sammy Saab; Steven-Huy Han; Xia; Hiatt; R. W. Busuttil

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.


Hepatology | 2011

Liver transplant recipient survival benefit with living donation in the model for endstage liver disease allocation era

Carl L. Berg; Robert M. Merion; Tempie H. Shearon; Kim M. Olthoff; Robert S. Brown; Talia Baker; Gregory T. Everson; Johnny C. Hong; Norah A. Terrault; Paul H. Hayashi; Robert A. Fisher; James E. Everhart

Receipt of a living donor liver transplant (LDLT) has been associated with improved survival compared with waiting for a deceased donor liver transplant (DDLT). However, the survival benefit of liver transplant has been questioned for candidates with Model for Endstage Liver Disease (MELD) scores <15, and the survival advantage of LDLT has not been demonstrated during the MELD allocation era, especially for low MELD patients. Transplant candidates enrolled in the Adult‐to‐Adult Living Donor Liver Transplantation Cohort Study after February 28, 2002 were followed for a median of 4.6 years. Starting at the time of presentation of the first potential living donor, mortality for LDLT recipients was compared to mortality for patients who remained on the waiting list or received DDLT (no LDLT group) according to categories of MELD score (<15 or ≥15) and diagnosis of hepatocellular carcinoma (HCC). Of 868 potential LDLT recipients (453 with MELD <15; 415 with MELD ≥15 at entry), 712 underwent transplantation (406 LDLT; 306 DDLT), 83 died without transplant, and 73 were alive without transplant at last follow‐up. Overall, LDLT recipients had 56% lower mortality (hazard ratio [HR] = 0.44, 95% confidence interval [CI] 0.32‐0.60; P < 0.0001). Among candidates without HCC, mortality benefit was seen both with MELD <15 (HR = 0.39; P = 0.0003) and MELD ≥15 (HR = 0.42; P = 0.0006). Among candidates with HCC, a benefit of LDLT was not seen for MELD <15 (HR = 0.82, P = 0.65) but was seen for MELD ≥15 (HR = 0.29, P = 0.043). Conclusion: Across the range of MELD scores, patients without HCC derived a significant survival benefit when undergoing LDLT rather than waiting for DDLT in the MELD liver allocation era. Low MELD candidates with HCC may not benefit from LDLT. (HEPATOLOGY 2011;54:1313–1321)


Archives of Surgery | 2011

Comparative Analysis of Resection and Liver Transplantation for Intrahepatic and Hilar Cholangiocarcinoma: A 24-Year Experience in a Single Center

Johnny C. Hong; Christopher M. Jones; John P. Duffy; Henrik Petrowsky; Douglas G. Farmer; Samuel W. French; Richard S. Finn; Francisco Durazo; Sammy Saab; Myron J. Tong; Jonathan R. Hiatt; Ronald W. Busuttil

OBJECTIVES To compare the survival difference between 2 surgical modalities in the treatment of locally advanced intrahepatic and hilar cholangiocarcinoma (CCA) and to identify factors that predict mortality. DESIGN Retrospective study. SETTING University transplant center. PATIENTS Of the 132 patients with a diagnosis of CCA treated from February 1, 1985, through June 30, 2009, 75 had metastatic disease at presentation and were excluded from the study, whereas 57 patients were candidates for surgical therapy. Tumor type was intrahepatic in 37 patients and hilar in 20 patients. Surgical therapy included orthotopic liver transplant (OLT) in 38 patients and combined radical bile duct resection with partial hepatectomy (RR) in 19 patients. RESULTS Tumors were locally advanced in 35 of 37 patients (95%) with intrahepatic tumors and 16 of 20 patients (80%) with hilar tumors. Adjunctive therapy was used in 35 patients (61%). The 5-year tumor recurrence-free patient survival was significantly higher in the OLT group compared with the RR group (33% vs 0%; P = .05). In the OLT group, neoadjuvant and adjuvant therapies resulted in better patient survival compared with no therapy or adjuvant therapy only (47% vs 20% vs 33%, respectively; P = .03). Multivariate factors predictive of worse survival outcomes included hilar CCA, multifocal tumors, perineural invasion, and RR as the treatment modality compared with OLT. Tumor sizes--5 cm or larger for intrahepatic and 3 cm or larger for hilar CCA--were not predictors of poor outcome. CONCLUSION Orthotopic liver transplant in combination with neoadjuvant and adjuvant therapies is superior to RR with adjuvant therapy in locally advanced intrahepatic and hilar CCA.

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Michael A. Zimmerman

Medical College of Wisconsin

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Hasan Yersiz

University of California

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Barry D. Kahan

University of Texas Health Science Center at Houston

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Fady M. Kaldas

University of California

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Sammy Saab

University of California

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Joo Hyun Kim

Medical College of Wisconsin

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