Treatment of PTLD with rituximab and CHOP reduces the risk of renal graft impairment after reduction of immunosuppression

First Use of Upfront Polatuzumab Vedotin in Post-transplant Lymphoproliferative Disorder: A Case Report

Post-transplant lymphoproliferative disorder (PTLD) is a condition that is highly variable in presentation but life-threatening for post-transplant, immunosuppressed patients. Current standard management in PTLD sees the use of a chemoimmunotherapy regimen similar to the management of diffuse large B-cell lymphoma. Here, we discuss the case of a 33-year-old male with a history of renal transplant, hemodynamically stable, who presented with fevers and night sweats lasting one month. Investigations revealed multiple masses in his liver, the largest of which was biopsied and revealed diffuse large B-cell lymphoma. PTLD is an important malignancy in patients who have received immunosuppression, but the treatment is heterogeneous, based on subtype and patient status. This case, where the addition of polatuzumab to the standard rituximab, cyclophosphamide, doxorubicin, and vincristine (R-CHOP) regimen led to favorable results, demonstrates the potential for a new standard treatment regimen for this disease.

Management and Outcomes of Diffuse Large B-cell Lymphoma Post-transplant Lymphoproliferative Disorder in the Era of PET and Rituximab: A Multicenter Study From the Australasian Lymphoma Alliance

There are limited data on post-transplant lymphoproliferative disorder (PTLD) in the era of positron emission tomography (PET) and rituximab (R). Furthermore, there is limited data on the risk of graft rejection with modern practices in reduction in immunosuppression (RIS). We studied 91 patients with monomorphic diffuse large B-cell lymphoma PTLD at 11 Australian centers: median age 52 years, diagnosed between 2004 and 2017, median follow-up 4.7 years (range, 0.5-14.5 y). RIS occurred in 88% of patients. For patients initially treated with R-monotherapy, 45% achieved complete remission, rising to 71% with the addition of rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone (R-CHOP) for those not in complete remission. For patients initially treated with R-CHOP, the complete remission rate was 76%. There was no difference in overall survival (OS) between R-monotherapy and R-chemotherapy patients. There was no difference in OS for patients with systemic lymphoma (n = 68) versus central nervous system (CNS) involvement (n = 23) (3-y OS 72% versus 73%; P = 0.78). Treatment-related mortality was 7%. End of treatment PET was prognostic for patients with systemic lymphoma with longer OS in the PET negative group (3-y OS 91% versus 57%; P = 0.01). Graft rejection occurred in 9% (n = 4 biopsy-proven; n = 4 suspected) during the entire follow-up period with no cases of graft loss. RIS and R-based treatments are safe and effective with a low likelihood of graft rejection and high cure rate for patients achieving complete remission with CNS or systemic PTLD.

Posttransplant Lymphoproliferative Disorder Following Kidney Transplantation: A Review

Posttransplant lymphoproliferative disorder (PTLD) is one of the most feared complications following kidney transplantation. Over a 10-year period, the risk of PTLD in kidney transplant recipients (KTRs) is 12-fold higher than in a matched nontransplanted population. Given the number of kidney transplants performed, KTRs who experience PTLD outnumber other organ transplant recipients who experience PTLD. Epstein-Barr virus infection is one of the most important risk factors for PTLD, even though 40% of PTLD cases in contemporary series are not Epstein-Barr virus-associated. The overall level of immunosuppression seems to be the most important driver of the increased occurrence of PTLD in solid organ transplant recipients. Reduction in immunosuppression is commonly accepted to prevent and treat PTLD. Although the cornerstone of PTLD treatment had been chemotherapy (typically cyclophosphamide-doxorubicin-vincristinr-prednisone), the availability of rituximab has changed the treatment landscape in the past 2 decades. The outcome of PTLD in KTRs has clearly improved as a result of the introduction of more uniform treatment protocols, improved supportive care, and increased awareness and use of positron emission tomography combined with computed tomography in staging and response monitoring. In this review, we will focus on the most recent data on epidemiology, presentation, risk factors, and management of PTLD in KTRs.

Multimodality imaging features, treatment, and prognosis of post-transplant lymphoproliferative disorder in renal allografts: A case report and literature review

RATIONALE

Among patients with post-transplant lymphoproliferative disorder (PTLD), there is a high incidence of immunosuppressed transplant recipients. It is necessary to make an early diagnosis to increase the likelihood of a good prognosis.

PATIENT CONCERNS

We report a case of a 54-year-old female patient who developed PTLD after liver and kidney transplantation.

DIAGNOSES

We aimed to analyze the standard diagnosis and follow-up of PTLD with imaging. Radiologists need to be familiar with all imaging modalities when dealing with PTLD, including ultrasonography, computed tomography, magnetic resonance imaging, positron-emission tomography/computed tomography.

INTERVENTIONS

The initial treatment included both reduction of immunosuppression and rituximab. Then the treatment strategy changed to rituximab and chemotherapy. Finally, the treatment strategy combined glucocorticoid therapy.

OUTCOMES

The patient was in a stable condition at the 3-month follow-up.

LESSONS

Systematic evaluation of the various imaging modalities, treatment options, and prognoses of PTLD in renal allografts suggested that in cases with a poor prognosis, the proper imaging modalities provide essential information with regard to the determination of the appropriate treatment.

Graft outcomes following diagnosis of post-transplant lymphoproliferative disease in pediatric kidney recipients: a retrospective study

Data related to graft outcomes following post-transplant lymphoproliferative disease (PTLD) in pediatric kidney transplantation are scarce. Data were analyzed retrospectively from 12 children (eight boys) for 3 years after diagnosis of PTLD, with a loss of follow-up after 2 years in two of 12. In all cases, intensity of immunosuppressive therapy was reduced, which switched from calcineurin inhibitor to a mammalian target of rapamycin (mTOR) inhibitor in ten cases. Nine children were treated with six doses of rituximab according to the PED-PTLD-2005 protocol, with additional treatment in one child as per protocol. One patient received EuroNet-PHL C1. In four patients, donor-specific antibodies were detected after PTLD diagnosis at 3, 4, 5 and 7 years, respectively. One patient developed chronic antibody-mediated rejection (cAMR) 12 years after diagnosis, losing the graft 1 year later. Three patients with recurrence of the original disease also lost their grafts, one at the time of diagnosis of PTLD, and two after 4 years. Range-based analysis of variance showed that there was no decrease in estimated GFR at 1, 2, or 3 years after diagnosis of PTLD (P = 0.978). In conclusion, treatment of PTLD with reduced immunosuppression is safe and efficient. This may be due to B-cell-depleting therapy of PTLD with rituximab.

Post-transplant lymphoproliferative disorder after solid-organ transplant in children

The post-transplant lymphoproliferative disorders (PTLD) are a diverse group of potentially life-threatening conditions affecting organ transplant recipients. PTLD arises in the setting of an attenuated host immunologic system that is manipulated to allow a foreign graft but then fails to provide adequate immune surveillance of transformed malignant or premalignant lymphocytes. The diversity of biological behavior and clinical presentation makes for a challenging clinical situation for those involved in the care of children with PTLD occurring after solid-organ transplantation. This review details a large transplant center's multidisciplinary approach to monitoring for PTLD and systematic approach to intervention, which has been essential for early recognition and successful treatment.

Risk-adapted Treatment for Severe B-Lineage Posttransplant Lymphoproliferative Disease After Solid Organ Transplantation in Children

BACKGROUND

Optimal management of posttransplant lymphoproliferative disease (PTLD) remains to be defined due to heterogeneity of this condition and lack of predictors of the outcome. Here we report our experience with pediatric PTLD nonresponsive to immunosuppression (IS) withdrawal, managed after stratification into high and low risk according to the presenting features.

METHODS

This is a single-center retrospective review of prospectively enrolled patients. From 2001 to 2011, 17 children were diagnosed with severe B-lineage, CD20+, PTLD after a median of 37 months (range, 5-93) from liver (12), heart (4), or multiorgan (1) transplantation. Treatment was tailored on 2 risk groups: (1) standard-risk (SR) patients received IS reduction and rituximab; (2) high-risk (HR) patients received IS discontinuation, rituximab and polychemotherapy.

RESULTS

The cumulative incidence of rejection at 1 and 5 years after the diagnosis of PTLD was 35% (95% confidence interval [95% CI], 18-69%) and 53% (33-85%), respectively, whereas the disease-free survival at 1 and 5 years was 94% (95% CI, 65-99%) and 75% (45-90%), respectively. Three children died, PTLD-free, from different transplant-related complications: primary nonfunction after retransplantation (liver), cytomegalovirus disease 21 months after PTLD treatment (liver), graft dysfunction 25 months after PTLD (heart).

CONCLUSIONS

Severe B-lineage PTLD after solid organ transplantation may be classified as SR or HR and treated accordingly with a tailored protocol obtaining a satisfactory long-term outcome. This approach accomplishes the control of lymphoproliferation in severe forms as well as the minimization of toxicity in milder PTLDs.

Post-transplant lymphoproliferative disorder in adult renal transplant recipients: survival and prognosis

Post-transplant lymphoproliferative disorder (PTLD) is a rare, serious complication following solid organ transplantation, with an incidence of 2.6 cases per 1000 patient years. Optimal treatment strategies and risk stratifications specific to kidney transplantation are lacking and PTLD mortality remains high. This study investigated survival and prognosis in 89 cases of PTLD presenting over 44 years at Manchester Royal Infirmary. Patient survival following diagnosis was 72% at 6 months, 67% at 1 year and 54% at 3 years. In multivariate analysis, a poorer 3 year survival was associated with acute kidney injury at diagnosis (p = 0.0001), impaired renal function (p = 0.04), early onset (p = 0.02), T cell disease (p = 0.02) and previous treatment with anti-thymocyte globulin (p = 0.04). The inclusion of graft function adds prognostic value to risk stratification and should be explored further. Strategies to improve survival should include timing and choice of immuno-chemotherapy, preparation for dialysis and aggressive surveillance for sepsis and treatment toxicity.

Cessation of immunosuppression during chemotherapy for post-transplant lymphoproliferative disorders in renal transplant patients

BACKGROUND

The optimal reduction of immunosuppressive therapy (IST) in renal transplant patients with post-transplant lymphoproliferative disorders (PTLDs) is uncertain. As chemotherapy is immunosuppressive, IST may be stopped during this time without compromising graft function. Subsequent long-term reduction of IST reduces relapse risk, but may increase risk of graft rejection.

METHODS

We performed a retrospective, matched cohort study of adult renal transplant patients in whom IST was ceased during chemotherapy and resumed at lower dose (calcineurin inhibitor at 50%, prednisolone ≤10 mg daily, no third agent) approximately 6 weeks after chemotherapy. Outcomes were compared with those of renal transplant patients without PTLD, matched for creatinine at equivalent time post-transplant that PTLD was diagnosed in cases, as well as for age, gender and year of transplant.

RESULTS

Twenty-four cases of PTLD occurring at a median of 9.2 years post-transplant were compared with 83 matched controls. PTLD cases were followed for a median of 11.9 years. Using competing risks analysis, time to 25% increase in serum creatinine was not significantly different between the two groups [adjusted hazard ratio (HR) 1.8, 95% confidence interval (CI) 0.89-3.6]. Similar results were obtained using multivariable Cox regression analysis (HR 1.19, 95% CI 0.44-3.23). Only one PTLD case experienced a ≥25% increase in creatinine <6 months after IST cessation in the setting of progressive PTLD and death. Three cases recommenced dialysis, compared with three controls (HR 2.5, 95% CI 0.47-13.00). Five-year patient survival rates for cases and controls were 70 and 94%, respectively (P = 0.01).

CONCLUSIONS

IST can be safely ceased during chemotherapy for PTLD in renal transplant patients. Furthermore, long-term reduction in IST is not associated with a significant difference in renal function deterioration. Prospective trials are needed to address the optimal reduction of IST in PTLDs.

Post-transplant lymphoproliferative disorder presenting as a tumor adjacent to the renal allograft: A case report and review of the literature

Post-transplant lymphoproliferative disorder (PTLD) is a potentially fatal complication of solid organ transplantation. The current report presents the case of a 42-year-old male who developed PTLD within the first year following renal transplantation. The disorder manifested as a tumor adjacent to the lower pole of the renal allograft and resulted in urinary obstruction. Durable complete remission was achieved as a result of surgical resection followed by a reduction in immunosuppression and low-dose rituximab-based chemotherapy, indicating that this therapeutic strategy may be safe and effective for the treatment of specific cases of localized and resectable PTLD.

Rituximab therapy and reduction of immunosuppression to rescue graft function after renal posttransplantation lymphoproliferative disorder found by macrohematuria in a pancreas and kidney transplant recipient: a case report

INTRODUCTION

Posttransplantation lymphoproliferative disorder (PTLD) remains an uncommon complication of solid organ transplantation, with a high mortality rate reported after conventional therapies. Epstein-Barr virus (EBV) may cause PTLD, but most EBV infections after transplantation are clinically silent reactivations, so the detection of PTLD is often delayed. Recently we experienced the rare case of intrarenal graft PTLD found by macrohematuria in a simultaneous pancreas and kidney transplant recipient. The grafts were saved by treatments with rituximab, cyclophosphamide, hydroxydaunorubicin, and prednisone-based chemotherapy (R-CHOP) after reduction of immunosuppression (IR).

METHODS

This 37-year-old man with insulin-dependent diabetes underwent simultaneous pancreas and kidney transplantation (SPK) with enteric drainage. Six months after transplantation, he displayed macrohematuria, which we investigated by blood tests, computer tomography (CT) scan, positron emission tomography (PET)-CT, and magnetic resonance imaging, recognizing a tumor in the transplanted renal graft. An open biopsy showed a CD20-positive PTLD. We started treatments with IR, rituximab (375 mg/m(2), weekly for 2 cycles) and R-CHOP therapy: rituximab (375 mg/m(2)) plus CHOP every 3 weeks for 6 cycles.

RESULTS

IR and R-CHOP therapy achieved a complete remission (CR). CR has continued for 14 months at the time of writing. The maximum level of EBV DNA was 259 copies/μg DNA, but 2 months after these therapies, the level had decreased to normal. The patient had no impairment of pancreas and kidney graft functions.

CONCLUSIONS

The outcome of intragraft PTLD in the kidney of an SPK recipient suggested that the negative impact of IR on graft function may be compensated by the immunosuppressive effects of rituximab, allowing reduced immunosuppression during chemotherapy.

CNI withdrawal for post-transplant lymphoproliferative disorders in kidney transplant is an independent risk factor for graft failure and mortality

Post-transplantation lymphoproliferative disorders (PTLD) are associated with poor patient and graft survival. The risk of rejection and subsequent graft loss are increased by the reduction of immunosuppression therapy, the cornerstone of PTLD treatment. This multicentre, retrospective, nonrandomized cohort study includes 104 adults who developed PTLD after renal or simultaneous renal/pancreatic transplantation between 1990 and 2007. It examines the effect of calcineurin inhibitor (CNI) withdrawal on long-term graft and patient survival. At 10 years postonset of PTLD, the Kaplan-Meier graft loss rate was 43.9% and graft loss or death with functioning graft was 64.4%. Cox multivariate analysis determined risk factors of graft loss as PTLD stage greater than I-II and CNI withdrawal, and for graft loss and mortality, these remained risk factors along with age over 60 years. Type and location of PTLD, year of diagnosis, and chemotherapy regime were not independent risk factors. Multivariate analysis determined CNI withdrawal as the most important risk factor for graft loss (HR = 3.07, CI 95%: 1.04-9.09; P = 0.04) and death (HR: 4.00, CI 95%: 1.77-9.04; P < 0.001). While long-term stable renal function after definitive CNI withdrawal for PTLD has been reported, this review determined that withdrawal is associated with reduced graft and patient survival.

Chemoimmunotherapy and withdrawal of immunosuppression for monomorphic posttransplant lymphoproliferative disorders

BACKGROUND

Monomorphic PTLDs are the most aggressive type of PTLD occurring after SOT. Current guidelines for treatment suggest a stepwise approach that includes a reduction of immunosuppression (RIS) with or without rituximab, followed by chemotherapy if there is no response. Nevertheless, recommendations regarding the extent and duration of RIS are nonstandardized and RIS as an initial strategy might be associated with an unacceptably high frequency of graft loss and disease progression.

PATIENTS AND METHODS

We reviewed the outcome of a combination program of aggressive chemoimmunotherapy and complete withdrawal of immunosuppression in treating 22 patients with monomorphic PTLD between January 1995 and August 2012.

RESULTS

Twelve of 22 patients (55%) received CHOP-R (cyclophosphamide, doxorubicin, vincristine, prednisone, and rituximab) every 2 weeks (dose-dense CHOP-R) and 10 patients received other doxorubicin-based regimens. There was no treatment-related mortality. Complete response was seen in 91% of patients. Median OS was 9.61 years (95% confidence interval (CI), 5.21-10.74). Median progression-free survival was 5.39 years (95% CI, 2.10-10.74). The graft rejection rate was 18% (95% CI, 0.03-0.34).

CONCLUSION

The use of aggressive chemoimmunotherapy in combination with the withdrawal of immunosuppression approach yields excellent results and should be prospectively studied in a multi-institutional setting.

Therapeutic options in post-transplant lymphoproliferative disorders

Post-transplantation lymphoproliferative disorders (PTLD) are the second most frequent malignancies after solid organ transplantation and cover a wide spectrum ranging from polyclonal early lesions to monomorphic lymphoma. Available treatment modalities include immunosuppression reduction, immunotherapy with anti-B-cell monoclonal antibodies, chemotherapy, antiviral therapy, cytotoxic T-cell therapy as well as surgery and irradiation. Owing to the small number of cases and the heterogeneity of PTLD, current treatment strategies are mostly based on case reports and small, often retrospective studies. Moreover, many studies on the treatment of PTLD have involved a combination of different treatment options, complicating the evaluation of individual treatment components. However, there has been significant progress over the last few years. Three prospective phase II trials on the efficacy of rituximab monotherapy have shown significant complete remission rates without any relevant toxicity. A prospective, multicenter, international phase II trial evaluating sequential treatment with rituximab and CHOP-based chemotherapy (cyclophosphamide, doxorubicin, vincristine, prednisone) is ongoing and preliminary results have been promising. Cytotoxic T-cell therapy targeting Epstein-Barr virus (EBV)-infected B cells has shown low toxicity and high efficacy in a phase II trial and will be a future therapeutic option at specialized centers. Here, we review the currently available data on the different treatment modalities with a focus on PTLD following solid organ transplantation in adult patients.

Late-onset post-transplantation lymphoproliferative disorders after kidney transplantation: a monocentric study over three decades

BACKGROUND

Late-onset post-transplantation lymphoproliferative disorders (PTLDs) occur 1 year after transplantation and are associated with poor prognosis. Initial treatment usually involves a reduction in immunosuppressive treatment. While early-onset PTLDs have a good prognosis following RI, this approach is generally inadequate for late-onset PTLDs. We assessed the specific outcome of late-onset PTLDs after kidney transplantation during the past three decades.

METHODS

We reviewed the clinical and biological data of 52 kidney transplant recipients who developed late-onset PTLDs at our centre between 1980 and 2010. We compared clinical features, long-term outcome and renal prognosis of late-onset PTLDs both before and after the era of rituximab.

RESULTS

Before 2000, 38% of the patients underwent surgery and 76% received chemotherapy either immediately or after surgery. After 2000, rituximab was administrated to 70% of the patients either alone (23%) or in combination with chemotherapy (77%). Chemotherapy alone was administrated in 26% of the cases. Before and after 2000, complete remission was achieved in 38 and 87% of the cases, respectively (P = 0.0005). The 5-year overall survival (OS) was 33.3 and 69% (P = 0.003), and 5-year disease-free survival was 37.5 and 80%, respectively (P = 0.19). Renal function was preserved in 70% of the cases at the end of the follow-up.

CONCLUSIONS

This study shows an increase in OS and low graft loss for patients with late-onset PTLDs during the last decade, which may be attributed to multiple changes in clinical practice, including a more standardized treatment and the use of rituximab in combination with chemotherapy.

Managing post-transplant lymphoproliferative disorders in solid-organ transplant recipients: a review of immunosuppressant regimens

Post-transplant lymphoproliferative disorders (PTLD) are a heterogeneous group of potentially life-threatening complications that occur after solid organ and bone marrow transplantation. Risk factors for acquiring PTLD are type of organ transplanted, age, intensity of immunosuppression, viral infections such as Epstein-Barr virus (EBV) and time after transplantation. Due to a dearth of well designed prospective trials, treatment for PTLD is often empirical, with reduction in immunosuppression accepted as the first step. Rituximab, a monoclonal antibody directed against the CD20 antigen of immature B cells, is often used as monotherapy after reduction in immunosuppression, although this is associated with a high risk of relapse if patients have at least one of the following risk factors: age greater than 60 years, elevated lactate dehydrogenase levels and Eastern Cooperative Oncology Group Score between 2 and 4. For such patients, rituximab should be considered in combination with CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone), particularly if high-grade PTLD is present. Although widely prescribed, the use of ganciclovir for PTLD remains controversial as EBV-transformed cells lack the thymidine kinase necessary for ganciclovir activation. Newer antivirals that combine ganciclovir with activators of cellular thymidine kinase have shown promising results in preclinical studies. In the absence of controlled trials, surgery may be indicated for localized disease and radiotherapy for patients with impending spinal cord compression or disease localized to the central nervous system or orbit. Future interventions may include adoptive immunotherapy, intravenous immunoglobulin, mammalian target of rapamycin inhibitors, monoclonal antibodies to interleukin-6 and galectin-1, and even EBV vaccination. Although several trials are in progress, it is necessary to wait for the long-term outcome of these studies on risk of PTLD relapse.

Tumor-specific but not nonspecific cell-free circulating DNA can be used to monitor disease response in lymphoma

Recently, nontumor specific circulating DNA was shown to be elevated in a broad range of lymphomas, implicating a role as a potential biomarker. Epstein-Barr virus' (EBV) presence within a proportion of lymphomas implies EBV-DNA has potential as a lymphoma-specific disease response biomarker. However, application would be restricted to EBV-associated lymphomas. Neither detailed comparison has been performed of lymphoma-specific versus nonspecific DNA as disease response biomarkers nor have the kinetics of circulating DNA during treatment been established, and the optimal methodology remains unknown. We prospectively evaluated DNA levels and clinical response of 63 lymphoma patients. DNA was measured in paired serum, plasma, and cell samples at five predetermined time-points taken prior, during and following treatment. Both cell-free (c-f) circulating EBV-DNA (in EBV-associated lymphoma) and nonspecific c-f DNA levels (in all lymphomas) were elevated and discriminatory at presentation compared to healthy controls. Nonspecific c-f DNA was significantly associated with baseline serum lactate dehydrogenase. Within EBV-associated lymphomas at presentation, there was a strong correlation between specific and nonspecific circulating c-f DNA (r = 0.9, P < 0.0001). However, only c-f EBV-DNA correlated with clinical/radiological response. In addition, c-f EBV-DNA, and not nonspecific c-f DNA, provided an early marker of relapsed and refractory disease. Serum versus plasma, and single versus multiple-copy EBV-gene targets were equivalent. Lymphoma-specific DNA is a disease response biomarker; however, nonspecific DNA reflected neither lymphoma-specific DNA nor therapeutic response. Lymphoma disease response can be monitored by blood tests, but new lymphoma-specific biomarkers need to be identified to broaden applicability.

Sequential treatment with rituximab followed by CHOP chemotherapy in adult B-cell post-transplant lymphoproliferative disorder (PTLD): the prospective international multicentre phase 2 PTLD-1 trial

BACKGROUND

Post-transplantation lymphoproliferative disorder (PTLD) develops in 1-10% of transplant recipients and can be Epstein-Barr virus (EBV) associated. To improve long-term efficacy after rituximab monotherapy and to avoid the toxic effects of CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone) chemotherapy seen in first-line treatment, we initiated a phase 2 trial to test whether the subsequent use of rituximab and CHOP would improve the outcome of patients with PTLD.

METHODS

In this international multicentre open-label phase 2 trial, treatment-naive adult solid-organ transplant recipients diagnosed with CD20-positive PTLD who had failed to respond to upfront immunosuppression reduction received four courses of rituximab (375 mg/m(2) intravenously) once a week followed by 4 weeks without treatment and four cycles of CHOP every 3 weeks. In case of disease progression during rituximab monotherapy, CHOP was started immediately. Supportive therapy with granulocyte-colony stimulating factor after chemotherapy was mandatory and antibiotic prophylaxis was recommended. The primary endpoint was treatment efficacy measured as response rates in all patients who completed treatment with rituximab and CHOP, per protocol, and response duration, in all patients who completed all planned therapy and responded. Secondary endpoints were frequency of infections, treatment-related mortality, and overall survival. This study is registered at ClinicalTrials.gov, number NCT01458548.

FINDINGS

74 patients were enrolled between Dec 12, 2002 and May 5, 2008, of whom 70 patients were eligible to receive treatment. PTLD was of late type in 53 (76%) of 70 patients, monomorphic in 67 (96%) of 70, and histologically EBV associated in 29 (44%) of 66 cases. Four of 70 patients did not receive CHOP. 53 of 59 patients had a complete or partial response (90%, 95% CI 79-96), of which 40 (68%, 55-78) were complete responses. At data cutoff (June 1, 2011) median response duration in the 53 patients who had responded to treatment had not yet been reached (>79·1 months). The main adverse events were grade 3-4 leucopenia in 42 of 62 patients (68%, 55-78) and infections of grade 3-4 in 26 of 64 patients (41%, 29-53). Seven of 66 patients (11%, 5-21) had CHOP-associated treatment-related mortality. Median overall survival was 6·6 years (95% CI 2·8-10·4; n=70).

INTERPRETATION

Our results support the use of sequential immunochemotherapy with rituximab and CHOP in PTLD.

FUNDING

F Hoffmann-La Roche, Amgen Germany, Chugaï France.

Fludarabine, cyclophosphamide, doxorubicin (FCD), and rituximab: a remission induction therapy for aggressive pediatric post-transplant lymphoproliferative disease (PTLD)

Management of aggressive, usually late-occurring, post-transplant lymphoproliferative disorders (PTLDs), a life-threatening complication after solid organ transplants, remains controversial. Four children affected by aggressive CD20+ PTLDs received a chemo-immunotherapy regimen for remission induction based on fludarabine, cyclophosphamide, doxorubicin, and rituximab, associated with a rapid discontinuation of immunosuppression (IS). Subsequent consolidation chemotherapy consisted of Berlin-Frankfurt-Münster-modified blocks. All patients achieved a complete remission, which persisted for 25, 68+, 80+, and 103+ months after diagnosis. Therapy was well tolerated. No patients developed allograft rejection during PTLD treatment. Our experience suggests that this chemo-immunotherapeutic approach may be an effective treatment strategy while allowing for a concomitant discontinuation of IS.

Malignancies confined to disused arteriovenous fistulae in renal transplant patients: an important differential diagnosis

BACKGROUND

Swelling in an arteriovenous fistula (AVF) is commonly caused by thrombosis, aneurysm and infection. However, due to the increased risk of malignancy after transplantation, this should also be considered.

PATIENTS

We discuss 4 patients with malignancy confined to an AVF after renal transplantation presenting in a 2-year period. Angiosarcoma was diagnosed in 3 patients and the other had post-transplant lymphoproliferative disorder (PTLD). Angiosarcoma behaves aggressively and 2 of our patients died within 6 months of diagnosis. There are 6 previous cases and 5 died within 16 months of diagnosis. PTLD at AVFs has not been documented previously.

CONCLUSION

Malignancy at an AVF is a rare but important differential that can impact significantly on patient morbidity and mortality. Predilection for malignancy at an AVF is not understood. We review the literature and discuss possible aetiologies.

Epstein-Barr Virus-related post-transplant lymphoproliferative disorders: pathogenetic insights for targeted therapy

Post-transplant lymphoproliferative disorder (PTLD) is a spectrum of major, life-threatening lymphoproliferative diseases occurring in the post-transplant setting. The majority of PTLD is of B-cell origin and is associated with several risk factors, the most significant being Epstein-Barr virus (EBV) infection. EBV's in vitro transforming abilities, distinctive latency, clonality within the malignant cells and response to targeted therapies implicate a critical role in the biology of PTLD. This minireview focuses on EBV-related PTLD pathogenesis, in particular the interplay between aspects of the EBV life cycle and latency with nonviral factors resulting in the wide spectrum of histology and clinical presentations encountered in PTLD. With the increased prevalence of transplantation a rise in the incidence of PTLD may be expected. Therefore the importance of laboratory and animal models in the understanding of PTLD and the development of novel therapeutic approaches is discussed.

Management of posttransplant lymphoproliferative disorders following solid organ transplant: an update

Development of secondary malignancies is a well-known complication of solid organ transplant, with skin cancer and lymphoproliferative disorders being most frequently observed. Posttransplant lymphoproliferative disorders, caused by diminished immune surveillance, represent a broad spectrum of pathological and clinical disorders, ranging from benign conditions to very aggressive lymphomas. Here we review treatment options for adult patients experiencing posttransplant lymphoproliferative disorders following solid organ transplant.

Lymphoproliferative disorders after solid organ transplantation-classification, incidence, risk factors, early detection and treatment options

Posttransplant lymphoproliferative disorder (PTLD) is a heterogeneous disease group of benign and malignant entities. The new World Health Organisation classification introduced in 2008 distinguishes early lesions, polymorphic, monomorphic and classical Hodgkin lymphoma-type PTLD. Based on the time of appearance, early and late forms can be identified.PTLDs are the second most frequent posttransplantation tumors in adulthood, and the most frequent ones in childhood. The incidence varies with the transplanted organ-from 1%-2% following kidney transplantation to as high as 10% following thoracic organ transplantation-due to different intensities in immunosuppression. Immunocompromised state and Epstein-Barr virus (EBV) infection are the two major risk factors.In Europe and the US approximately 85% of PTLDs are of B-cell origin, and the majority are EBV-associated. Symptoms are often unspecific; extranodal, organ manifestations and central nervous system involvement is common. Early lesions respond well to a decrease in immunosuppression. Malignant entities are treated with rituximab, chemotherapy, radiotherapy and surgical therapy. Adoptive T-cell transfer represents a promising therapeutic approach. The prognosis is favorable in early PTLD, and poor in late PTLD. Five-year survival is 30% for high-grade lymphomas. The prognosis of EBV-negative lymphomas is worse.Lowering the risk of PTLD may be achieved by low dose maintenance immunosuppression, immunosuppressive drugs inhibiting cell proliferation, and special immunotherapy (e.g. interleukin-2 inhibitors). Early detection is especially important for high risk-e.g. EBV-negative-patients, where the appearance of EBV-DNA and the increase in its titer may help.

Post-transplant lymphoproliferative disorder in view of the new WHO classification: a more rational approach to a protean disease?

Post-transplant lymphoproliferative disorders (PTLDs) are serious, life-threatening complications of solid-organ transplantation (SOT) and bone marrow transplantation leading to a high mortality (30-60%). PTLD represents a heterogeneous group of lymphoproliferative diseases. They become clinically relevant because of the expansion of transplantation medicine together with the development of potent immunosuppressive drugs. Although the diagnostic morphological criteria of different forms of PTLD are commonly known, rapid and correct diagnosis is not always easy. Because of the limited number of clinical trials, a consensus is lacking on the optimal treatment of PTLD. This review focuses on incidence, risk factors, clinical picture of the disease and diagnostic tools including histopathology relating to the new classification introduced in 2008 by the World Health Organisation (WHO) and treatment of PTLD.

Post-transplant lymphoproliferative disorder in children: recent outcomes and response to dual rituximab/low-dose chemotherapy combination

PTLD is a major complication after transplantation. Treatment options for PTLD are not standardized, usually sequential, starting with reduction in immunosuppression. Recently, we have used a dual combination of rituximab and reduced dose chemotherapy (R/C) directly after failed RI. We retrospectively identified 30 pediatric PTLD cases across four organ systems at our center from 1995 to 2008. We assessed recent outcomes of PTLD in children, comparing the responses to different regimens. Two-yr failure-free survival was best in renal and heart recipients (80-88%), followed by liver (57%) and lung (0%). Of note, two patients were Epstein-Barr peripheral blood viral load low positive but tumor EBER negative. Three patients had no detectable viral load but were EBER positive. The R/C regimen (n = 8) had the highest CR rate (100%), low recurrence (12%) and lowest mortality (12%). Interferon (n = 4) had 75% CR, 33% recurrence and 25% mortality. Rituximab/prednisone (n = 5) had 80% CR, 50% recurrence and 20% mortality. Other chemotherapy (n = 7, including all 4 T-cell PTLDs) had 57% CR, 0% recurrence and 14% mortality. Direct dual R/C combination therapy after failed RI is effective and offers another treatment option for B-cell PTLD.

Treatment advances in posttransplant lymphoproliferative disease

PURPOSE OF REVIEW

Epstein-Barr virus-associated posttransplant lymphoproliferative disease (PTLD) is a life-threatening complication of organ transplantation. As we continue to observe improved outcomes of patients living after solid or hematopoietic stem cell transplantation, we can expect to see a parallel increase in the incidence of PTLD. Several innovative therapeutic approaches are currently under development to add to our arsenal of treatment strategies in this devastating disease.

RECENT FINDINGS

The past decade has witnessed significant progress in the understanding and treatment of PTLD. The tolerability and effectiveness of standard treatment regimens, such as a reduction in immunosuppression, rituximab, and chemotherapy, have been confirmed and improved upon. Newer options for treatment demonstrating significant promise include antiviral therapy with arginine butyrate, as well as Epstein-Barr virus-specific cytotoxic T-cell therapy.

SUMMARY

Both the heterogeneous PTLD population and the lack of standardized and evidence-based treatment approaches make treatment a difficult decision for the clinician. This article reviews and updates the evidence behind accepted strategies such as reduction in immunosuppression, rituximab, and chemotherapy, as well as explores novel and effective therapeutic modalities including antiviral therapy with arginine butyrate and adoptive allogeneic T-cell therapy.