Section 13. Short-course pretransplant antiviral therapy is a feasible and effective strategy to prevent hepatitis C recurrence after liver transplantation in genotype 2 patients

Recipient blood group does not affect hepatocellular carcinoma recurrence after living donor liver transplantation in Korea

PURPOSE

This study assessed whether or not the ABO blood type affects the incidence of HCC recurrence after living donor liver transplantation (LDLT).

METHODS

This retrospective observational study included 856 patients with hepatocellular carcinoma (HCC) who underwent LDLT between January 2006 and December 2016 at the Asan Medical Center.

RESULTS

This study included 324 patients (37.9%) with blood type A, 215 (25.1%) with blood type B, 210 (24.5%) with blood type O, and 107 (12.5%) with blood type AB. ABO-incompatible LT was performed in 136 (15.9%) patients. The independent risk factors for the disease-free survival (DFS) were maximal tumor diameter, microvascular invasion, and Milan criteria. The only independent risk factor for the overall survival (OS) was microvascular invasion. The ABO blood group did not affect the DFS (P = 0.978) or OS (P = 0.261). The DFS according to the ABO blood group did not differ significantly between the ABO-compatible (p = 0.701) and ABO-incompatible LDLT recipients (p = 0.147). The DFS according to the ABO blood group did not differ significantly between patients within the Milan criteria (p = 0.934) and beyond the Milan criteria (p = 0.525). The DFS did not differ significantly between recipients with and without type A blood (p = 0.941).

CONCLUSIONS

This study demonstrated that the ABO blood group system had no prognostic impact on the oncological outcomes of patients undergoing LT for HCC.

The critical role of therapeutic plasma exchange in ABO-incompatible liver transplantation

BACKGROUND

The shortage of donor liver restricts liver transplantation (LT). Nowadays, donor liver with ABO blood group incompatibility between donor and recipient has become an option to expand the source of donor liver. Although it is now possible to perform ABO-incompatible (ABO-I) LT, antibody-mediated rejection (AMR) has been recognized as the primary cause of desperate outcomes after ABO-I LT. Anti-A/B antibody is the trigger of immune response to ABO-I LT graft injury. Therapeutic plasma exchange (TPE) can quickly reduce the titer of plasma antibodies and effectively inhibit humoral immunity.

DATA SOURCES

We searched PubMed and CNKI databases using search terms "therapeutic plasma exchange", "ABO-incompatible liver transplantation", "ABO-I LT", "liver transplantation", "LT", "antibody-mediated rejection", and "AMR". Additional publications were identified by a manual search of references from key articles. The relevant publications published before September 30, 2020 were included in this review.

RESULTS

Different centers have made different attempts on whether to use TPE, when to use TPE and how often to use TPE. However, the control standard of lectin revision level is always controversial, the target titer varies significantly from center to center, and the standard target titer has not yet been established. TPE has several schemes to reduce antibody titers, but there is a lack of clinical trials that provide standardized procedures.

CONCLUSIONS

TPE is essential for ABO-I LT. Hence, further research and clinical trials should be conducted to determine the best regimen for TPE to remove ABO antibodies and prevent AMR.

Over 500 Liver Transplants Including More Than 400 Living-Donor Liver Transplants in 2019 at Asan Medical Center

BACKGROUND

More than 400 liver transplants were performed at Asan Medical Center (AMC) in 2011, and over 500 liver transplants including 420 living-donor liver transplants (LDLTs) were performed in 2019. Herein, we report the methodology of these procedures.

METHODS

Since the first adult LDLTs at AMC using the left and right lobes were successfully performed, various innovative techniques and approaches have been developed: modified right lobe, dual graft, donor exchange for ABO incompatibility, expansion of indications and no-touch techniques for hepatocellular carcinoma, intraoperative cine-portogram and additional intervention for large collaterals, management of portal vein thrombosis (PVT) and stenosis, salvage LDLT after major hepatectomy, and timely LDLT for patients with acute-on-chronic liver failure.

RESULTS

Four hundred twenty LDLTs in 403 adult and 17 pediatric patients and 85 deceased-donor liver transplants in 74 adult and 11 pediatric patients were performed. The number of deceased-donor liver transplants remained constant since 2011, but the number of LDLTs increased steadily. One hundred thirty patients (25.7%) required urgent liver transplantations and 24 patients with acute-on-chronic liver failure underwent LDLT. PVT including grade 1,2,3, and 4 was reported in 91 patients (18.0%), and Yerdel's grade 2, 3, and 4 PVT was reported in 47 patients (51.6%); all patients with PVT were successfully treated. Adult LDLTs for hepatocellular carcinoma and ABO incompatibility accounted for 52.6% and 24.3% of the cases, respectively. In-hospital mortality in 2019 was 2.97%.

CONCLUSION

Continual efforts to overcome challenging problems in LDLT with various innovations and dedication of the team members during the perioperative period to improve patient outcomes were crucial in increasing the number of liver transplantations at Asan Medical Center.

Impact of ABO-incompatibility on hepatic artery thrombosis in living donor liver transplantation

Background

The current era of rituximab-based regimens brought improved survival in ABO-incompatible (ABO-I) living donor liver transplantation (LDLT). Nevertheless, the actual risk for hepatic artery thrombosis (HAT) still remains to be investigated. The aim of this study was to evaluate the impact of ABO-incompatibility on HAT in adult LDLT patients.

Methods

Patients who received ABO-I LDLT were compared to those who received ABO-compatible (ABO-C) LDLT with a special focus on HAT.

Results

A total of 378 patients underwent LDLT from January 2012 to February 2018. Of those, ABO-I LDLT was performed in 78 consecutive patients. The other 300 patients with ABO-C LDLT constituted the comparator group. No significant differences were observed between the two groups in baseline and perioperative characteristics. HAT occurred in 11 (2.9%) patients, 2 and 9 patients in ABO-I and ABO-C LDLT groups, respectively, which didn't show any significant difference between the two groups (P=0.84). All were categorized into early HAT. Immediate revascularization by intraarterial thrombolysis was successfully employed in 8 patients. Surgical revision of anastomosis and retransplantation were performed in 1 and 2 patients, respectively. No one-year mortality was related to HAT in the two groups. The overall outcomes including biliary complications made no significant difference between the two groups.

Conclusions

ABO-incompatibility has no adverse impact on the incidence and treatment outcome of HAT in the current rituximab-based desensitization.

ABO-Incompatible Liver Transplantation - A Review of the Historical Background and Results

ABO-incompatible liver transplantation (ABOi LT) using conventional immunosuppression has been considered a contraindication due to the high risk for antibody-mediated complications potentially resulting in graft loss. However, organ shortage has led to the development of anti-A/B antibody reducing immunosuppressive protocols which have made the outcome after living donor (LD) ABOi LT equivalent to that achieved with LD ABO-compatible (ABOc). The experience of deceased donor (DD) ABOi LT is however still limited. In this article, we discuss the historical background and the results after ABOi LT, in the setting of both LD and DD transplantation. We also discuss the remaining hurdles and future strategies in the breaching of the ABO barrier for LT.

Feasibility of Monotherapy by Rituximab Without Additional Desensitization in ABO-incompatible Living-Donor Liver Transplantation

BACKGROUND

Rituximab is a cornerstone in the regimens of desensitization for ABO-incompatible living-donor liver transplantation (ABO-i LDLT) that makes this modality an acceptable option for liver transplantation. Plasmapheresis (PP) to reduce anti-ABO antibody titer and local infusion (LI) therapy were practiced as the strategies for desensitization before the application of rituximab and were reported as additional treatments. The aim of this study was to clarify the feasibility of monotherapy by rituximab without any additional desensitization treatments in ABO-i LT.

METHODS

Forty patients receiving ABO-i LDLT with rituximab were enrolled in this retrospective study. The patients were divided into 2 groups: the rituximab with pretransplant PP and posttransplant LI (RPL) group (n = 20) and the rituximab monotherapy (RM) without any additional treatment group (n = 20). The groups were then compared in terms of the rates of patient survival, antibody-mediated rejection (AMR), and infection.

RESULTS

The 1-, 3-, and 5-year patient survival rates were 85%, 85%, and 85% in the RPL group and 89%, 80%, and 80% in the RM group, respectively. There was no significant difference in patient survival between the 2 groups. There were no episodes of AMR in either group. The RM group had a lower rate of fungal and viral infections than the RPL group.

CONCLUSIONS

Pretransplant rituximab without additional treatments yielded satisfactory outcomes comparable to that with additional treatments, such as PP and LI.

Outcome of ABO-incompatible adult living-donor liver transplantation for patients with hepatocellular carcinoma

BACKGROUND & AIMS

Living-donor liver transplantation (LDLT) can simultaneously cure hepatocellular carcinoma (HCC) and underlying liver cirrhosis, improving long-term results in patients with HCC. ABO-incompatible LDLT could expand the living-donor pool, reduce waiting times for deceased-donor liver transplantation, and improve long-term survival for some patients with HCC.

METHODS

We retrospectively reviewed the medical records of patients undergoing LDLT for HCC from November 2008 to December 2015 at a single institution in Korea. In total, 165 patients underwent ABO-incompatible and 753 patients underwent ABO-compatible LDLT for HCC. ABO-incompatible recipients underwent desensitization to overcome the ABO blood group barrier, including pretransplant plasma exchange and rituximab administration (300-375 mg/m² /body surface area).

RESULTS

We performed 1:1 propensity score matching and included 165 patients in each group. 82.4% of ABO-incompatible and 83.0% of -compatible LDLT groups had HCC within conventional Milan criteria, respectively, and 92.1% and 92.7% of patients in each group had a Child-Pugh score of A or B. ABO-incompatible and -compatible LDLT groups were followed up for 48.0 and 48.7 months, respectively, with both groups showing comparable recurrence-free survival rates (hazard ratio [HR] 1.14; 95% CI 0.68-1.90; p = 0.630) and overall patient-survival outcomes (HR 1.10; 95% CI 0.60-2.00; p = 0.763).

CONCLUSIONS

These findings suggested that ABO-incompatible liver transplantation is a feasible option for patients with HCC, especially for those with compensated cirrhosis with HCC within conventional Milan criteria.

LAY SUMMARY

Despite hypothetical immunological concerns that the desensitization protocol for breaking through the ABO blood group barrier might have a negative impact on the recurrence of hepatocellular carcinoma, our experience demonstrated no significant differences in the long-term overall survival and recurrence-free survival rates between patients receiving ABO-compatible or ABO-incompatible liver transplantation. In conclusion, results from our institution indicated that ABO-incompatible living-donor liver transplantation constitutes a potentially feasible option for patients with hepatocellular carcinoma, especially those with compensated cirrhosis with hepatocellular carcinoma within conventional Milan criteria.

A simplified protocol using rituximab and immunoglobulin for ABO-incompatible low-titre living donor liver transplantation

BACKGROUND & AIMS

No consensus has been reached regarding optimal treatment strategies for ABO-incompatible (ABO-I) living donor liver transplantation (LDLT). We introduce a simplified protocol using rituximab and intravenous immunoglobulin (IVIG).

METHODS

Data were analysed on adult patients who underwent ABO-I LDLT of which protocol added rituximab (300 mg/m² ) before surgery and IVIG (0.8 g/kg) on post-operative days 1 and 4 to the conventional immunosuppressive regimen used in ABO-compatible (ABO-C) LDLT, without plasmapheresis, splenectomy or graft local infusion. The outcomes were compared with those of ABO-C LDLT by 1:2 propensity score-matched analysis.

RESULTS

Consecutive 43 ABO-I LDLT patients were identified between 2014 and 2016. Before desensitization, the median isoagglutinin titre was 1:8 (range, 1:2-1:64). The titre was reduced to 4 (range, 0-16) at the time of LDLT. None showed a rebound rise of isoagglutinin titres. No antibody-mediated rejection occurred. Biliary stricture was the most common complication with an incidence of 30.2%. A comparator group of 86 ABO-C LDLT patients were selected. There was no statistical difference in the overall complication rate including acute cellular rejection, biliary complications and infection between ABO-I and ABO-C groups. The 3-year cumulative patient survival rates in the ABO-I and ABO-C groups were 82.4% and 85.9% respectively (P = .115).

CONCLUSIONS

A simplified protocol using rituximab and IVIG for ABO-I LDLT was safe and effective in achieving sufficient desensitization and comparable outcomes in patients with the titre no higher than 1:64.

Rituximab Induction to Prevent the Recurrence of PSC After Liver Transplantation-The Lessons Learned From ABO-Incompatible Living Donor Liver Transplantation

Background

Multiple studies have failed to reveal an effective method for preventing the recurrence of primary sclerosing cholangitis (PSC) after liver transplantation (LTx). A national study conducted in Japan revealed several risk factors for the recurrence after living donor LTx (LDLTx); however, recipients of ABO-blood type incompatible (ABO-I) LTx were excluded from the previous analysis. In the present study, we investigated the efficacy of an immunosuppressive protocol in ABO-I LTx on the recurrence of PSC after LDLTx.

Methods

We conducted a national survey and analyzed the outcome of recipients who underwent ABO-I LDLTx for PSC (n = 12) between 1994 and 2010 in 9 centers and compared the outcome with that of ABO-compatible LDLTx for PSC (n = 96). The key elements of the immunosuppressive regimen in ABO-I LTx are plasma exchange sessions to remove existing antibodies, and the use of immunosuppression to control humoral immunity. Rituximab was added to the immunosuppression regimen from 2006 onward; 5 patients received rituximab perioperatively.

Results

All 7 recipients who underwent ABO-I LDLTx before 2006 (who did not receive rituximab) died of infection (n = 3), antibody-mediated rejection (n = 1), ABO-incompatibility associated cholangiopathy (n = 1) or recurrence of PSC (n = 2). In contrast, we found that all 5 recipients from 2006 (who were treated with rituximab) retained an excellent graft function for more than 7 years without any recurrence of PSC.

Conclusions

The findings of this study shed light on the efficacy of a novel strategy to prevent the recurrence of PSC and the possible mechanisms provided by rituximab treatment are discussed.

Splenectomy during whole liver transplantation: a morbid procedure which does not adversely impact long-term survival

BACKGROUND

Indications for splenectomy (SP) during whole liver transplantation (LT) remain controversial and SP is often avoided because of common complications. We aimed to evaluate specific complications of these combined procedures.

METHODS

Data were retrospectively analysed. Splenectomy was performed in patients with splenorenal shunt and/or splenic artery aneurysms or hypersplenism. Patients undergoing simultaneous transplantation and splenectomy (LTSP group) were matched to a non-splenectomy group (LT group).

RESULTS

Between 1994 and 2013, we included 47 and 94 patients in LTSP and LT groups, respectively. The LTSP patients had a higher rate of pre-LT portal vein thrombosis (PVT). The LTSP group had a longer operative time and greater blood loss. Mean follow-up was 101 months and 5-year survivals were identical (LTSP 85% vs LT 88%, p = 0.831). Hospital morbidity and rejection incidence were comparable, whereas de novo PVT (34% vs 2%, p < 0.0001) and infection (47% vs 25%, p = 0.014) rates were higher after SP.

CONCLUSION

Splenectomy during LT is technically demanding and exposes recipients to a higher thrombosis rate, therefore portal vein patency must be specifically assessed postoperatively. In selected recipients, SP can be performed without increased mortality but at the price of worsening outcome as evidenced by greater risk of infection and PVT.

Single-Center Experience of ABO-Incompatible Living-Donor Liver Transplantation With a New Simplified Intravenous Immunoglobulin Protocol: A Propensity Score-Matching Analysis

The outcomes of patients who undergo ABO-incompatible (ABO-I) living-donor liver transplantation (LDLT) have markedly improved as strategies have become more innovative and advanced. Here, we describe 25 cases of ABO-I LDLT with a simplified protocol and compare the outcomes to those of ABO-compatible LDLT. We analyzed outcomes via a retrospective review of 182 adult LDLT cases including 25 ABO-I LDLTs from January 2011 to December 2014. Propensity scoring was used to compare the groups. The desensitization protocol included plasma exchange, rituximab, and intravenous immunoglobulin without local infusion therapy. The triple immunosuppression protocol consisted of tacrolimus and steroids with mycophenolate mofetil; a splenectomy was not routinely performed. The median age of recipients was 51 years (range, 35-66 years), and the median mean Model for End-Stage Liver Disease (MELD) score was 15 (range, 7-37). The initial ranges of isoagglutinin IgM and IgG titers were 1:1 to 1:256 and 1:4 to 1:2048, respectively. There were no significant differences in patient demographics or perioperative variables between the groups. Although significant rebound elevation in anti-ABO antibody during the postoperative period was observed in 3 cases, neither C4d staining nor clinical signs of antibody-mediated rejection was apparent in these cases. No diffuse intrahepatic biliary stricture was encountered in any ABO-I LDLT patient within a mean follow-up of 22.6 ± 17.2 months. Moreover, no significant difference in overall or graft survival was observed between the groups. ABO-I LDLT can be performed safely under this new simplified protocol and may be proposed when ABO-compatible donors are unavailable.

ABO-Incompatible Adult Living Donor Liver Transplantation Under the Desensitization Protocol With Rituximab

ABO incompatibility is no longer considered a contraindication for adult living donor liver transplantation (ALDLT) due to various strategies to overcome the ABO blood group barrier. We report the largest single-center experience of ABO-incompatible (ABOi) ALDLT in 235 adult patients. The desensitization protocol included a single dose of rituximab and total plasma exchange. In addition, local graft infusion therapy, cyclophosphamide, or splenectomy was used for a certain time period, but these treatments were eventually discontinued due to adverse events. There were three cases (1.3%) of in-hospital mortality. The cumulative 3-year graft and patient survival rates were 89.2% and 92.3%, respectively, and were comparable to those of the ABO-compatible group (n = 1301). Despite promising survival outcomes, 17 patients (7.2%) experienced antibody-mediated rejection that manifested as diffuse intrahepatic biliary stricture; six cases required retransplantation, and three patients died. ABOi ALDLT is a feasible method for expanding a living liver donor pool, but the efficacy of the desensitization protocol in targeting B cell immunity should be optimized.

Results of ABO-incompatible liver transplantation using a simplified protocol at a single institution

BACKGROUND

Because of the development of various desensitization strategies, ABO-incompatible (ABOi) living donor liver transplantation (LDLT) has become a feasible option for patients with end-stage liver disease. However, there has been no united desensitization protocol for ABOi LDLT. We analyzed the outcomes after establishment of simplified protocol without splenectomy, intravenous immunoglobulin, and local infusion therapy.

METHODS

We analyzed 19 ABOi LDLT cases that had been performed between January 2012 and December 2013, without splenectomy and local infusion. We used a single dose of rituximab (375 mg/m(2)) 10 days before transplantation and several series of plasma exchange according to the recipients' iso-agglutinin titer-to-target titer ratio of 1:32.

RESULTS

Nineteen recipients received ABOi LTs from living donors. The mean initial immunoglobulin (Ig) M and IgG anti-ABO titers were 76.63 ± 78.81 (range, 8∼256) and 162.53 ± 464.1 (0∼2048). We performed preoperative plasma exchange to 16 recipients (mean number of sessions, 3.58; range, 1-10). After surgery, 9 patients received plasma exchange (mean, 1.84; range 1∼14). One death occurred as the result of pneumonia (5.3%). There were 4 cases of acute rejections (21.1%), and all of them were treated successfully with steroid pulse or thymoglobulin. Antibody-mediated rejection and graft failure did not occur. Six cases of postoperative complications (31.6%) occurred, including 3 cases of infections. There were 2 cases of biliary anastomotic stricture (10.5%) and 1 case of portal vein stenosis (5.3%).

CONCLUSIONS

ABOi LDLT with the use of simplified protocol can be safely performed without increased risk of antibody-mediated rejection and other complications.

Adult Living Donor Liver Transplantation Across ABO-Incompatibility

The objective of this study was to evaluate the results of adult ABO-incompatible living donor liver transplantation (LDLT).ABO-incompatible LDLT is an aggressive treatment that crosses the blood-typing barrier for saving lives from liver diseases. Although graft and patient survival have been improved recently by various treatments, the results of adult ABO-incompatible LDLT require further evaluation.Two regimens were designed based on isoagglutinin IgG and IgM titers and the time course of immunological reactions at this institute. When isoagglutinin IgG and IgM titers were ≤64, liver transplantation was directly performed and rituximab (375 mg/m) was administrated on postoperative day 1 (regimen I). When isoagglutinin titers were >64, rituximab (375 mg/m) was administered preoperatively with or without plasmapheresis and boosted on postoperative day 1 (regimen II). Immunosuppression was achieved by administration of mycophenolate mofetil, tacrolimus, and steroids.Forty-six adult ABO-incompatible and 340 ABO-compatible LDLTs were performed from 2006 to 2013. The Model for End-Stage Liver Disease scores for ABO-incompatible recipients ranged from 7 to 40, with a median of 14. The graft-to-recipient weight ratio ranged from 0.61% to 1.61% with a median of 0.91%. The 1-, 3-, and 5-year survival rates were 81.7%, 75.7%, and 71.0%, respectively, for ABO-incompatible LDLT recipients, compared to 81.0%, 75.2%, and 71.5% for ABO-C recipients (P = 0.912). The biliary complication rate was higher in ABO-incompatible LDLT recipients than in the ABO-compatible recipients (50.0% vs 29.7%, P = 0.009).In the rituximab era, the blood type barrier can be crossed to achieve adult ABO-incompatible LDLT with survival rates comparable to those of ABO-compatible LDLT, but with more biliary complications.