Post‐transplant lymphoproliferative disorder in pediatric intestinal transplant recipients: A literature review

Intestinal transplantation is a successful treatment for children with intestinal failure, but has many potential complications. PTLD, a clinically and histologically diverse malignancy, occurs frequently after intestinal transplantation and can be fatal. The management of this disease is particularly challenging. The rejection‐prone intestinal allograft requires high levels of immunosuppression, a precondition for PTLD. While EBV infection clearly plays a role in disease pathogenesis, the relatively naïve immune system of children is another likely contributor. As a result, pediatric intestine recipients have a higher risk of developing PTLD than other solid organ recipients. Other risk factors for disease development such as molecular and genomic changes that precipitate malignant transformation are not fully understood, especially among children. Studies on adults have started to describe the molecular pathogenesis of PTLD, but the genomic landscape of the malignancy remains largely undefined in pediatric intestinal transplant patients. In this review, we describe what is known about PTLD in pediatric patients after intestinal transplant and highlight current knowledge gaps to better direct future investigations in the pediatric population.     

Post‐transplant lymphoproliferative disorders and other malignancies after pediatric intestinal transplantation: Incidence,clinical features and outcome

PTLDs are a well‐recognized and potentially fatal complication after intestinal transplantation. We analyzed the incidence, clinical features, and outcome in a 63 intestinal transplantation series performed in our unit between October 1999 and July 2011. Types of graft included ISB (n = 23), LSB (n = 20), and MV (n = 20). Patients were categorized into three groups of immunosuppression: I (n = 43) received basiliximab, tacrolimus, and steroids; II (n = 11) thymoglobulin and tacrolimus, and III (n = 9) alemtuzumab and tacrolimus. EBV status was serially assessed. All PTLD cases were biopsied to establish histopathological diagnosis. The incidence of PTLD was 14.2% (9/63). Median onset of PTLD after transplant was four months (range: 0.5–28), within first postoperative year in 6 (66.6%) patients. Fever was the most common symptom. Graft removal was needed in four patients (44%). The patient survival rate was 66.6% (6/9). We have not found any association between PTLD and immunosuppression regimen or transplant type. However, there was a statistical association with EBV active infection.     

Epstein‐Barr viral load monitoring for diagnosing post‐transplant lymphoproliferative disorder in pediatric liver transplant recipients

This study aimed to investigate the incidence of PTLD in pediatric liver transplant recipients and the risk factors for the development of PTLD. We also determined clinically useful quantitative EBV PCR parameters for aiding in the diagnosis of EBV‐associated PTLD in the pediatric liver transplant recipients at our institute. We reviewed children < 18 years old who had undergone liver transplantations and quantitative analysis of whole blood EBV load at our institute from January 2006 to March 2015. A total of 142 liver transplant recipients were included, and their median age was 1.5 years. Clinically significant high‐level EBV DNAemia ≥ 10 000 copies/mL at least twice was observed in 53.5% and PTLD occurred in 9.9%. Among PTLD group, graft failure and mortality rate were as high as 21.4% and 14.3%, respectively. Deceased donor, presence of high‐level EBV DNAemia, and primary CMV infection following transplant were associated with an increased risk for PTLD in the multivariate analysis. The peak titer at 10 875 copies/mL could be used as a cutoff value with a sensitivity of 92.9% and a specificity of 37.9%; the rate of increase in EBV load suggested a sensitivity of 64.3% and a specificity of 70.9% at the cutoff value of 44 000 copies/mL/week. In conclusion, the incidence of PTLD following liver transplant in children was as high as 10%. PTLD is associated with significant morbidity and mortality. Close monitoring of EBV DNAemia is crucial for the early diagnosis and proper treatment of PTLD in pediatric liver transplant recipients.     

Intraventricular rituximab and systemic chemotherapy for treatment of central nervous system post-transplant lymphoproliferative disorder after kidney transplantation

Twombley K, Pokala H, Ardura MI, Harker-Murray P, Johnson-Welch SF, Weinberg A, Seikaly M. Intraventricular rituximab and systemic chemotherapy for treatment of central nervous system post-transplant lymphoproliferative disorder after kidney transplantation. Abstract: PTLD of the CNS is a rare complication of solid organ transplantation, and there are only case reports/series available in the literature. Current literature suggests that CNS PTLD carries a worse prognosis than PTLD outside the CNS, and most are of B-cell lineage, predominately monomorphic, and are associated with EBV infection. Because this disorder is so rare, there is no standard chemotherapy for pediatric patients with CNS PTLD and reported therapies for EBV-associated CNS PTLD are heterogeneous with mixed results. Since outcomes of CNS PTLD are historically poor, we attempted to develop a novel therapeutic treatment regimen. Based on a review of the literature and with the help of a multidisciplinary team, we created a regimen of chemotherapy that included dexamethasone and high-dose methotrexate in addition to intravenous and intraventricular Rituximab in two pediatric patients. The intraventricular chemotherapy succeeded in shrinking the tumor in both of our patients; however, as shown in the second case, the clinical outcome depends on the location of the tumor. Systemic and intraventricular therapies hold promise in the management of EBV-associated CNS PTLD; however the rarity of this entity prevents the development of well-designed studies necessary for the establishment of an evidence-based treatment standard.     

Post-transplant lymphoproliferative disorder following pediatric heart transplantation

Immunosuppression after heart transplantation is implicated in development of post-transplant lymphoproliferative disorder (PTLD). Despite a higher prevalence of PTLD in children, there is scarce knowledge about incidence, pathophysiologic mechanisms and risk factors for PTLD in pediatric recipients of cardiac allografts. We examined retrospectively the medical records of all 143 pediatric patients (mean age 9.2 +/- 6.1 yr) who received donor allografts between 1984 and 2002 and survived over 30 days. Five children (3.5%) developed PTLD over a mean follow-up period of 41.1 +/- 46.0 months. Time from transplant to diagnosis of PTLD ranged from 3.9 to 112 months (mean 48.0 +/- 41.9 months). Excluding PTLD, no other malignancies were found in this population. Actuarial freedom from PTLD was 99.2%, 99.2% and 96.2% at 1, 2, and 5 yr, respectively. Children who developed PTLD were more likely (by univariate analysis) to have been Rh negative (p = 0.01), Rh mismatched (p = 0.003), Epstein-Barr virus (EBV) seronegative (p = 0.001) and transplanted for congenital heart disease (p < 0.02). PTLD was associated with significant morbidity and mortality with a mean survival following diagnosis of 21.2 months. PTLD is a serious complicating outcome of cardiac transplantation that occurs in approximately 3.5% of children. Aside of immunosuppression, risk factors in this series for developing PTLD include EBV seronegativity and Rh negative status and mismatch. Non-hematogenous malignancies are rare in light of short allograft half-life.     

Post-transplantation lymphoproliferative disorders localizing to the gastrointestinal tract after liver transplantation: report of five pediatric cases

Post-transplantation lymphoproliferative disorder (PTLD) is a life-threatening complication of organ transplantation. PTLD can occur in every kind of organ transplantation. From July 1992 to July 2004, five patients were diagnosed at our transplantation center with PTLD after pediatric liver transplantation. During this period, there were 52 pediatric patients (<18 yr) receiving an orthotopic liver transplantation (OLT) at our center. All five patients had transmural gastrointestinal (GI) PTLD, which occurred mostly in the stomach and duodenum. Epstein-Barr virus (EBV) in situ was demonstrated in each case. EBV viral load was noted to be an important risk factor. Treatment included dose reduction of immunosuppressants and anti-CD20 antibody infusion. Chemotherapy, including cyclophosphamide, doxorubicin, vincristine, and prednisolone, was given to three patients. Four patients have survived more than 10 months until now after treatment. The one who was unresponsive to chemotherapy and anti-CD20 antibody had diffuse metastasis and died of systemic candidiasis. In our series, each PTLD involved the GI tract. The mechanism of this phenomenon is unclear, but these five cases indicate the high incidence of PTLD in pediatric solid organ transplantation.     

Epidemiology and outcome of chronic high Epstein‐Barr viral load carriage in pediatric kidney transplant recipients

The development of EBV infection and PTLD is normally associated with a high EBV viral load in peripheral blood. Observations have previously identified existence of a CHL carrier state that demonstrated variable outcomes based upon the organ which was transplanted. Data defining the incidence and outcome of CHL in pediatric KTx are not well described. The charts of children undergoing isolated KTx at Children's Hospital of Pittsburgh between January 2000 and December 2014 were retrospectively reviewed. EBV loads in the peripheral blood were routinely measured as part of surveillance protocols at our center. CHL was defined as the presence of high load for >50% of samples for ≥6 months. PTLD was defined histologically using WHO definitions. Of 188 isolated KTx recipients, we identified a total of 16 (8%) children who developed CHL carrier state. No patient developed EBV‐driven late‐onset PTLD. Age at the time of KTx was significantly lower in the CHL group (median 3.9 years, interquartile range: IQR 2.9‐6.6, P = .0004). Children in the CHL group were more likely to be EBV‐seronegative prior to KTx (94%, 15/16), compared to the UVL and LVL groups (55% and 50%, respectively, P < .002). The median duration of CHL carrier state was 20 months (IQR 10.7‐35.8). Fifteen of the 16 CHL carriers experienced spontaneous resolution of CHL carrier state. Children in the CHL group were younger at the time of primary EBV infection (P = .023). Finally, antiviral medication was not effective in either preventing or decreasing the EBV viral load in blood (P = .84). Overall incidence of late‐onset PTLD is very low compared to heart and intestinal transplant, even though KTx recipients can develop CHL carrier state. The CHL carriers in KTx recipients were EBV‐seronegative prior to transplant and were younger both at the time of KTx and at the time of primary EBV infection compared to those in the UVL and HVL groups. Antivirals did not prevent EBV infection or decrease EBV viral loads.     

Post-transplantation lymphoproliferative disorder in pediatric kidney-transplant recipients - A national study

Cleper R, Ben Shalom E, Landau D, Weissman I, Krause I, Konen O, Rahamimov R, Mor E, Bar‐Nathan N, Frishberg Y, Davidovits M. Post‐transplantation lymphoproliferative disorder in pediatric kidney‐transplant recipients – A national study. Abstract: PTLD is the most common malignancy in pediatric kidney‐transplant recipients. We examined the prevalence, clinical features, and outcome of PTLD in Israel. Twelve (4.4%) of 272 pediatric (<19 yr) kidney‐transplant recipients retrieved from a search of the NIKTR for 1991–2008 had acquired PTLD at a median of 3.2 yr post‐transplantation. PTLD‐affected patients were younger at transplantation (4.2 vs. 12.5 yr, p = 0.02), had a higher rate of OKT3 therapy for acute rejection (25% vs. 4%, p = 0.015), and 5/12 were EBV‐seropositive at transplantation. Graft dysfunction was the presenting sign in six (50%). PTLD was predominantly abdominal (83%) and B‐cell type (67%); T‐cell PTLD occurred exclusively in EBV‐seropositive patients. Treatment consisted of immunosuppression cessation (6/12, 50%), antiviral agents (7/12, 58%), anti‐CD20 monoclonal antibodies (4/12, 33%), and chemotherapy (6/12, 50%). Survival was 100% in the EBV‐naïve patients and 40% in the EBV‐seropositive patients. Graft loss occurred in three of eight survivors (37.5%). PTLD‐associated mortality risk was older age: 11.2 vs. 3.4 yr, longer dialysis: 15 vs. 6.5 months, T‐cell type disease (75%), later PTLD onset: 6.35 vs. 1.9 yr post‐transplantation and era of transplantation (43% mortality before vs. 20% after 2001). Pretransplantation EBV‐seronegative status might confer a survival benefit with early detected PTLD. EBV‐seropositive patients are at risk for aggressive late‐onset lethal PTLD.     

Cytotoxic T‐lymphocyte therapy for post‐transplant lymphoproliferative disorder after solid organ transplantation in children

EBV‐CTL immunotherapy targets EBV antigens expressed by tumor cells in PTLD. Data on outcome of EBV‐CTL in pSOT patients are limited. The aim of the study is to describe our experience with allogeneic, third‐party EBV‐CTL for the treatment of PTLD in pSOT patients in a single tertiary center. Retrospective review was performed of all pSOT patients who received EBV‐CTL for PTLD. PTLD was diagnosed using World Health Organization histologic criteria. EBV‐CTLs were derived from human leukocyte antigen‐typed, EBV‐seropositive third‐party donors, and cryopreserved and maintained by an accredited national blood transfusion service. Ten patients received EBV‐CTL for histologically proven PTLD from 1999 to 2016 following liver (n=5), combined intestinal/liver (n=4), and liver/kidney (n=1) transplantation. PTLD occurred at median age of 40 months (range: 12‐144) and median post‐transplant interval of 8 months (range: 2‐107). Seven had monomorphic, two had polymorphic, and one had Hodgkin‐type PTLD. All were of B‐cell origin and EBV‐positive on histology. EBV‐CTL achieved an overall remission rate of 80% (8 of 10). Transient adverse effects included fever, tachycardia, and vomiting. None developed graft‐versus‐host disease or opportunistic infections. EBV‐CTL is an effective treatment for PTLD in pSOT patients, with good remission rate and minimal toxicity.     

EBV lymphoproliferative disease of host origin after haploidentical stem cell transplantation

Post-transplant lymphoproliferative disease (PTLPD), due to the reactivation of Epstein-Barr virus (EBV), is a serious complication. The risk of the disorder increases with T-cell depletion methods, mismatched hematopoietic stem cell transplantation (HSCT), graft-versus-host disease (GVHD), and immunosuppression. In contrast to solid organ transplantation, where EBV is typically of recipient origin, the source of the EBV in HSCT recipients is donor-derived B-lymphocytes. In this report, we describe a 15-year-old girl who underwent HSCT from her father as treatment for acute myeloid leukemia (AML). She subsequently developed disseminated PTLPD involving multiple organ and nodal sites. Her neoplastic lymphoblasts were host-derived and refractory to rituximab treatment due to lack of CD20 expression.     

B‐Cell lymphoproliferative disorder not associated with Epstein‐Barr Virus in a child with relapsed acute lymphoblastic leukemia

Lymphoproliferative disorder (LPD) is described in only a few children receiving chemotherapy for cancer. In all of them, an association between LPD and EBV (Epstein‐Barr Virus) was found. We report on a patient who developed LPD not associated with EBV while receiving chemotherapy for relapsed acute lymphoblastic leukemia (ALL). Despite discontinuation of chemotherapy, administration of intravenous immunoglobulins and surgery the patient died. Growing experience with this disorder may allow better treatment options in the future and will show whether LPD not associated with EBV requires different therapeutic strategies. Med Pediatr Oncol 2003;40:13–17, © 2003 Wiley‐Liss, Inc.     

Treatment of pediatric plasma cell myeloma type post‐transplant lymphoproliferative disorder with modern risk‐directed therapy

Post‐transplant lymphoproliferative disorder (PTLD) related plasma cell neoplasms are rare in pediatric patients. We report a pediatric liver transplant recipient with plasma cell myeloma type PTLD. Cytogenetics included 1q duplication, associated with poor prognosis in adult multiple myeloma, and t(8;14). High‐risk cytogenetics has not been reported in pediatric plasma cell myeloma type PTLD. The patient was treated with bortezomib, dexamethasone, and lenalidomide with subsequent autologous stem cell transplant. He achieved a 6‐year remission, demonstrating tolerance to and efficacy of this modern myeloma regimen in a pediatric patient. Unfortunately, he subsequently died from complications of repeat liver transplant.     

Eosinophilic esophagitis in children following cardiac transplantation: Association with post‐transplant lymphoproliferative disorder and other transplant outcomes

Although cardiac transplantation is life‐saving, morbidities from immunosuppression are significant. EoE is a complication of calcineurin inhibitors following liver transplant causing feeding intolerance, weight loss, vomiting, and dysphagia. There are limited reports of EoE following heart transplantation. We performed a retrospective single‐center review of pediatric cardiac transplant patients from 2000 to 2010. A case–control analysis of patients with and without EoE was performed evaluating heart transplantation outcomes such as rates of rejection, CAV, PTLD, and graft loss. Eighty‐six transplants were performed in 84 patients; 34 (40%) underwent diagnostic endoscopy, and 10 (12%) had EoE. Median time to diagnosis of EoE was 3.7 yr (IQR: 2.0–5.2). There were no differences in demographics or use of induction medications between patients with or without EoE. Patients with EoE had fewer episodes of treated rejection (1.0 vs. 2.5; p = 0.04). Four of 10 (40%) EoE patients had PTLD compared with only 2/24 (8%) of those without EoE (p = 0.048; OR 7.33 [95% CI: 1.1–50.2]). There were no differences in CAV or graft loss between groups. EoE should be considered as a cause of GI symptoms in children after cardiac transplantation and may be associated with fewer rejection episodes and increased rates of PTLD, thus representing a marker of over‐immunosuppression.     

Successful treatment of a classic Hodgkin lymphoma‐type post‐transplant lymphoproliferative disorder with tailored chemotherapy and Epstein–Barr virus‐specific cytotoxic T lymphocytes in a pediatric heart transplant recipient

CHL type is the least common major form of EBV‐related PTLD but rarely occurs in pediatric recipients; development of CHL subsequent to other PTLD subtypes in the same transplant recipient is even more unusual. Because of its rarity, indications on the best treatment strategy are limited. Patients have been mostly treated with standard HL chemotherapy/radiotherapy, and prognosis seems more favorable than other monomorphic PTLDs. Herein, we describe a pediatric case of EBV‐associated, stage IV‐B, CHL arising in a heart allograft recipient eight yr after diagnosis of B‐cell polymorphic PTLD. The patient was successfully treated with adjusted‐dose HL chemotherapy and autologous EBV‐specific CTL, without discontinuation of maintenance immunosuppression. At two yr from therapy completion, the patient is in CR with stable organ function. With this strategy, it may be possible to reproduce the good prognostic data reported for CHL‐type PTLD, with decreased risk of organ toxicity or rejection.