Rituximab (chimeric anti-CD20 antibody) for posttransplant lymphoproliferative disorder after solid organ transplantation in adults: long-term experience from a single center.

BACKGROUND: Occurrence of posttransplant lymphoproliferative disorder (PTLD) after transplantation is known. Drastic reduction or withdrawal of immunosuppression with anti-viral therapy for Ebstein-Barr virus (EBV) is the primary treatment for all PTLD. Many PTLD are B cell in origin have CD20 antigen on the cell surface. Rituximab is a chimeric anti CD20 antibody, which has been used to treat PTLD with variable success. This study aims to report long-term experience with rituximab for PTLD from a single center. METHODS: Seventeen patients (13 male, 4 female, mean age 51.2 years) received rituximab to treat PTLD. Five patients received rituximab with drastic reduction in immunosuppression (primary). Nine patients received rituximab after failure of primary therapy (rescue) and three patients received it after resolution of PTLD (prophylactic). Mean follow-up period was 60 months. RESULTS: Overall 1-, 3-, and 5-year patient survivals were 64.7%, 47.1% and 35.3%, respectively. In the primary group, three patients had complete and one had partial response; however, only two (40%) patients are currently alive. In the rescue group, none of the patients had a complete response, four patients had partial response, and only two (22%) patients are currently alive. In the prophylactic group, two patients died at 28 and 41 months due to recurrence and graft failure, respectively. CONCLUSION: Sixty percent (3 of 5) of patients who received rituximab as primary therapy had complete resolution, and 44% (4 of 9) of patients who received it as rescue therapy had partial response. Overall 5-year patient survival was a disappointing 35%.

The absence of chronic rejection in pediatric primary liver transplant patients who are maintained on tacrolimus-based immunosuppression: a long-term analysis.

BACKGROUND: Although the outcome of liver transplantation has improved significantly during the past two decades, graft loss caused by chronic rejection after liver transplantation still occurs in 2% to 20% of recipients. The overall incidence of chronic rejection is also reported to be low in adult recipients, and risk factors have been identified. Chronic rejection is associated with the inability to maintain baseline immunosuppression. Additionally, the diagnoses of primary biliary cirrhosis, primary sclerosing cholangitis, autoimmune hepatitis, hepatitis B virus, and hepatitis C virus, common indications for liver transplantation in adults, are associated with a higher incidence of chronic rejection. Fortunately, these diagnoses are rarely seen in children. Little is known about chronic rejection in long-term pediatric liver transplant survivors. The purpose of this longitudinal study was to examine the incidence of biopsy-proven chronic rejection in long-term survivors of primary pediatric liver transplantation under tacrolimus-based immunosuppression. METHODS: From October 1989 to December 1992, 166 children (boys=95, girls=71; mean age=5.0+/-2.9 years) received a primary liver transplant. These patients were followed until March 2000 with a mean follow-up of 9+/-0.8 (range, 7.4-10.4) years. All liver biopsy specimens and explanted grafts were evaluated for evidence of chronic rejection using the International Banff Criteria. RESULTS: The mortality rate during the follow-up period was 15% (n=25). Retransplantation was required in 11% (n=18) of recipients. Actuarial patient and graft survival rates at 10 years were 84.9% and 80.1%, respectively. There were 535 liver biopsy samples available for evaluation, including the 18 explanted allografts. Biopsy specimens of three other functioning allografts showed evidence of chronic rejection. Immunosuppression had been discontinued or drastically reduced in these recipients because of life-threatening infections, noncompliance, or both. On restoring baseline immunosuppression, all three children had normalized liver function and the allografts were maintained; the liver transplant patients who are alive currently have normal liver functions. CONCLUSION: The findings of this study suggest that chronic rejection does not occur in pediatric liver transplant recipients receiving tacrolimus-based immunosuppression, provided baseline immunosuppression is maintained.

Posttransplant lymphoproliferative disorders in liver transplantation: a 20-year experience.

OBJECTIVE: To evaluate the incidence of posttransplant lymphoproliferative disease (PTLD) and the risk factors and the impact of this complication on survival outcomes in a large cohort of liver transplant recipients at a single institution. SUMMARY BACKGROUND DATA: Liver transplantation has been accepted as a therapeutic option for patients with end-stage liver disease since 1983, in large part due to the availability and reliance on the use of nonspecifically directed immunosuppression. However, as predicted and subsequently verified in 1968, an increased incidence of certain de novo malignancies has been observed, particularly with regards to lymphoid neoplasms. While many reports have confirmed and clarified the nature of PTLD, the literature is fraught with conflicting experience and outcomes with PTLD. METHODS: Four thousand consecutive patients who underwent liver transplants between February 1981 and April 1998 were included in this analysis and were followed to November 2001. The effect of recipient age at the time of transplant, recipient gender, diagnosis, baseline immunosuppression, grading of PTLD, and association with Epstein-Barr virus were compared. The causes of death were also examined. Treatment for PTLD varied over the 20-year period, but all included massive reduction or elimination of baseline immunosuppression. RESULTS: The 1-year patient survival for liver transplant patients with PTLD was 85%, while the overall patient survival for the entire cohort was 53%. The actuarial 20-year survival was estimated at 45%. The overall median time to PTLD presentation was 10 months, and children had an incidence of PTLD that was threefold higher than adults. Patient survival was better in children, in patients transplanted in the era of tacrolimus immunosuppression, in patients with polymorphic PTLD, and in those with limited disease. Interestingly, neither the presence or absence of Epstein-Barr virus nor the timing of PTLD presentation appeared to influence overall patient survival. Patients transplanted for alcohol-related liver disease had a similar incidence of PTLD but had a higher risk of mortality. CONCLUSIONS: While PTLD continues to pose problems in patients receiving liver transplants, improvements in patient survival have been observed over time. While it is too early to assess the impact of new advances in prophylaxis, diagnosis, and treatment, such approaches are based on an increased knowledge of the pathophysiology of PTLD.

A prospective randomized trial of mycophenolate mofetil in liver transplant recipients with hepatitis C.

Hepatitis C is the most common indication for liver transplantation (LT) in the United States. Recurrence of hepatitis C virus (HCV) infection post-LT remains a problem for which there is no completely satisfactory treatment. The aim of the present study is to evaluate mycophenolate mofetil (MMF), which has both immunosuppressive and antiviral properties, to determine whether it is associated with a difference in the rate of HCV recurrence and also examine its impact on patient and graft survival. Between August 1995 and May 1998, a total of 106 patients who were HCV positive before LT were randomized to tacrolimus (TAC) and prednisone versus TAC, prednisone, and MMF therapy. The rate of recurrence of HCV, patient and graft survival, incidences of rejection, and histological findings were examined. Fifty six patients were randomized to TAC and steroid therapy (double [D] drug; group D), and 50 patients were randomized to TAC, steroid, and MMF therapy (triple [T] drug; group T). Liver biopsies were performed when liver function was abnormal; protocol liver biopsies were not performed. Mean follow-up was 4.3 +/- 0.8 years. Actuarial patient survivals at 4 years were 72.6% in group D and 73.8% in group T (P = not significant). Actuarial graft survivals at 4 years were 65.6% in group D and 65.4% in group T. One patient in group D and 2 patients in group T underwent a second LT for recurrent HCV. One patient in each group died of recurrent HCV without re-LT. Twenty-six patients in group D (46.4%) and 23 patients in group T (46.0%) showed signs of recurrent HCV. Mean hepatitis activity index (HAI) scores were 7.4 +/- 2.7 in group D and 7.0 +/- 3.4 in group T, and mean fibrosis scores were 2.9 +/- 1.7 in group D and 2.6 +/- 1.1 in group T. The rate of rejection was 0.57/patient in each group for the entire follow-up period. None of these values reached statistical significance. Rates of HCV recurrence, graft loss or death from recurrent HCV, and 4-year actuarial patient and graft survival were not different between the groups. In liver transplant recipients with HCV, MMF has no impact on patient survival, graft survival, rejection, or rate of HCV recurrence based on biochemical changes and histological findings. In addition, there was no difference in HAI or fibrosis score between the two groups. Either MMF has no anti-HCV effect or its immunosuppressive properties overwhelm its antiviral effect in the clinical setting.