Poor outcome in post transplant lymphoproliferative disorder with pulmonary involvement after allogeneic hematopoietic SCT: 13 years' experience in a single institute

Outcomes for patients with EBV-positive PTLD post-allogeneic HCT after failure of rituximab-containing therapy

Epstein-Barr virus-positive (EBV+) post-transplant lymphoproliferative disease (PTLD) is an ultra-rare and aggressive condition that may occur following allogeneic hematopoietic cell transplant (HCT) due to immunosuppression. Approximately half of EBV+ PTLD cases are relapsed or refractory (R/R) to initial rituximab-containing therapy. There are limited treatment options and no standard of care for patients with R/R EBV+ PTLD, and little is known about their treatment history and outcomes. We performed a multinational, multicenter, retrospective chart review of patients with R/R EBV+ PTLD following HCT to describe patients' demographic and disease characteristics, treatment history, and overall survival (OS) from rituximab failure. Among 81 patients who received initial treatment with rituximab as monotherapy (84.0%) or in combination with chemotherapy (16.0%), median time from HCT to PTLD diagnosis was 3.0 months and median OS was 0.7 months. Thirty-six patients received a subsequent line of treatment. The most frequent causes of death were PTLD (56.8%), graft-versus-host disease (13.5%) and treatment-related mortality (10.8%). In multivariate analysis, early PTLD onset and lack of response to initial treatment were associated with mortality. This real-world study demonstrates that the prognosis of patients with R/R EBV+ PTLD following HCT remains poor, highlighting the urgent unmet medical need in this population.

Immune dysregulation as a leading principle for lymphoma development in diverse immunological backgrounds

Lymphoma is a heterogeneous group of malignancies arising from lymphocytes, which poses a significant challenge in terms of diagnosis and treatment due to its diverse subtypes and underlying mechanisms. This review aims to explore the shared and distinct features of various forms of lymphoma predisposing conditions, with a focus on genetic, immunological and molecular aspects. While diseases such as autoimmune disorders, inborn errors of immunity and iatrogenic immunodeficiencies are biologically and immunologically distinct, each of these diseases results in profound immune dysregulation and a predisposition to lymphoma development. Interestingly, the increased risk is often skewed towards a particular subtype of lymphoma. Patients with inborn errors of immunity in particular present with extreme forms of lymphoma predisposition, providing a unique opportunity to study the underlying mechanisms. External factors such as chronic infections and environmental exposures further modulate the risk of lymphoma development. Common features of conditions predisposing to lymphoma include: persistent inflammation, recurrent DNA damage or malfunctioning DNA repair, impaired tumor surveillance and viral clearance, and dysregulation of fundamental cellular processes such as activation, proliferation and apoptosis. Our growing understanding of the underlying mechanisms of lymphomagenesis provides opportunities for early detection, prevention and tailored treatment of lymphoma development.

Epstein-Barr virus-positive lymphoproliferative disorder manifesting as pulmonary disease in a patient with acute myeloid leukemia: a case report

Background

 Patients with lymphoproliferative disorders following hematopoietic stem cell transplant (HSCT) most commonly present with fever and lymphadenopathy within the first 5 months of transplant. Pulmonary post-transplant lymphoproliferative disorder (PTLD) is a particularly aggressive and rapidly progressive disease, with high morbidity and mortality. There are a very limited number of reported pulmonary PTLD cases following HSCT in patients with acute myeloid leukemia (AML). Early diagnosis and detection of pulmonary PTLD is critical given its high lethality. However, variable clinical presentations and nonspecific radiographic findings make pulmonary PTLD difficult to distinguish from other more common causes of pulmonary disease in AML patients.

Case presentation

Here, we describe a 68-year-old Caucasian man who presented for salvage induction therapy following relapse of his AML after a haploidentical allogeneic HSCT 10 months earlier. He developed recurrent fevers, dry cough, and hypoxemia, with chest computed tomography (CT) showing bibasilar consolidations and increased nodularity without increased lymphadenopathy. His symptoms initially improved with antibiotic and antifungal therapy, but his follow-up chest CT showed progression of disease despite symptomatic improvement. Epstein–Barr virus (EBV) was detected in his blood by polymerase chain reaction (PCR), and a lung biopsy revealed monomorphic PTLD with B cells positive for EBV. Unfortunately, the patient’s condition rapidly deteriorated, and he passed away prior to treatment initiation.

Conclusions

 To our knowledge, this is the first reported case of an AML patient developing pulmonary PTLD relatively late in his post-transplant course in the setting of relapsed disease and salvage therapy. Pulmonary PTLD, a rare but highly lethal disorder, can imitate the symptoms and radiographic findings of pneumonia, a common diagnosis in immunocompromised AML patients. This case illustrates the importance of considering pulmonary PTLD in the differential diagnosis for pulmonary disease in AML patients with a history of HSCT, especially in the setting of progressive radiographic findings despite broad antibacterial and antifungal therapy. Further, our case demonstrates the importance of biopsy and uninterrupted EBV DNA monitoring in the definitive diagnosis of PTLD, given nonspecific symptomatology and radiographic findings.

Post-transplantation lymphoproliferative disorder after haematopoietic stem cell transplantation

Post-transplantation lymphoproliferative disorder (PTLD) is a severe complication of haematopoietic stem cell transplantation (HSCT), occurring in a setting of immune suppression and dysregulation. The disease is in most cases driven by the reactivation of the Epstein-Barr virus (EBV), which induces B cell proliferation through different pathomechanisms. Beyond EBV, many factors, variably dependent on HSCT-related immunosuppression, contribute to the disease development. PTLDs share several features with primary lymphomas, though clinical manifestations may be different, frequently depending on extranodal involvement. According to the WHO classification, histologic examination is required for diagnosis, allowing also to distinguish among PTLD subtypes. However, in cases of severe and abrupt presentation, a diagnosis based on a combination of imaging studies and EBV-load determination is accepted. Therapies include prophylactic and pre-emptive interventions, aimed at eradicating EBV proliferation before symptoms onset, and targeted treatments. Among them, rituximab has emerged as first-line option, possibly combined with a reduction of immunosuppression, while EBV-specific cytotoxic T lymphocytes are effective and safe alternatives. Though prognosis remains poor, survival has markedly improved following the adoption of the aforementioned treatments. The validation of innovative, combined approaches is the future challenge.

Viral Infections in HSCT: Detection, Monitoring, Clinical Management, and Immunologic Implications

In spite of an increasing array of investigations, the relationships between viral infections and allogeneic hematopoietic stem cell transplantation (HSCT) are still controversial, and almost exclusively regard DNA viruses. Viral infections per se account for a considerable risk of morbidity and mortality among HSCT recipients, and available antiviral agents have proven to be of limited effectiveness. Therefore, an optimal management of viral infection represents a key point in HSCT strategies. On the other hand, viruses bear the potential of shaping immunologic recovery after HSCT, possibly interfering with control of the underlying disease and graft-versus-host disease (GvHD), and eventually with HSCT outcome. Moreover, preliminary data are available about the possible role of some virome components as markers of immunologic recovery after HSCT. Lastly, HSCT may exert an immunotherapeutic effect against some viral infections, notably HIV and HTLV-1, and has been considered as an eradicating approach in these indications.

18F-FDG PET/CT for Evaluation of Post-Transplant Lymphoproliferative Disorder (PTLD)

Post-transplant lymphoproliferative disorders (PTLD) are a spectrum of heterogeneous lymphoproliferative conditions that are serious and possibly fatal complications after solid organ or allogenic hematopoietic stem cell transplantation. Most PTLD are attributed to Epstein-Barr virus reactivation in B-cells in the setting of immunosuppression after transplantation. Early diagnosis, accurate staging, and timely treatment are of vital importance to reduce morbidity and mortality. Given the often nonspecific clinical presentation and disease heterogeneity of PTLD, tissue biopsy and histopathological analysis are essential to establish diagnosis and most importantly, determine the subtype of PTLD, which guides treatment options. Advanced imaging modalities such as ¹⁸F-FDG PET/CT have played an increasingly important role and have shown high sensitivity and specificity in detection, staging, and assessing treatment response in multiple clinical studies over the last two decades. However, larger multicenter prospective validation is still needed to further establish the clinical utility of PET imaging in the management of PTLD. Significantly, new hybrid imaging modalities such as PET/MR may help reduce radiation exposure, which is especially important in pediatric transplant patients.

Application of contrast-enhanced ultrasound in the diagnosis of post-transplant lymphoproliferative disease after hematopoietic stem cell transplantation: A case report

INTRODUCTION

Post-transplant lymphoproliferative disease (PTLD) is a series of proliferative diseases of the lymphatic system. Among patients receiving hematopoietic stem cell transplantation (HSCT), PTLD is a prevalent complication that severely affects rates of survival. Ultrasound plays an essential role in the early diagnosis of PTLD. Contrast-enhanced ultrasonography (CEUS) and CEUS-guided biopsy are critical procedures for tumor diagnosis.

PATIENT CONCERNS

Herein, we report the case of a 40-year-old male patient with acute lymphoblastic leukemia who received HSCT more than 1 year ago. Sonography revealed a small hypoechoic nodule in the liver four months after HSCT. Eight months after HSCT, larger and more nodules were observed via ultrasound; CT was used to identify the lesions.

DIAGNOSES

CEUS and CEUS-guided biopsy were performed, and the pathological diagnosis was PTLD.

INTERVENTIONS

The final clinical diagnosis was PTLD, and cyclophosphamide, epirubicin, and dexamethasone were administered as chemotherapy.

OUTCOMES

The patient was discharged after his condition improved.

CONCLUSION

Ultrasound can be used to effectively detect lesions of PTLD early after HSCT. Furthermore, CEUS and CEUS-guided biopsy were effective for early confirmatory diagnoses of PTLD after HSCT.

Mimickers of pulmonary lymphoma

There are multiple entities that involve the lung that have radiographic, clinical, and morphologic overlaps with pulmonary lymphoma. In this review, we will discuss these entities in detail and provide relevant updates.

Epstein-Barr Virus-Associated Post-Transplant Lymphoproliferative Disorders after Hematopoietic Stem Cell Transplantation: Pathogenesis, Risk Factors and Clinical Outcomes

Epstein-Barr virus (EBV) is a ubiquitous virus belonging to the human γ-herpes virus subfamily. After primary infection, EBV maintains a life-long latent infection. A major concern is that EBV can cause a diverse range of neoplasms and autoimmune diseases. In addition, patients undergoing hematopoietic stem cell transplantation or solid organ transplantation can experience post-transplant lymphoproliferative disorders (PTLDs) due to dysfunction or suppression of host’s immune system, or uncontrolled proliferation of EBV-infected cells. In recent years, the number of EBV-associated PTLD cases has increased. This review focuses on the current understandings of EBV-associated PTLD pathogenesis, as well as the risk factors and clinical outcomes for patients after allogeneic stem cell transplantation.

Respiratory failure in the hematopoietic stem cell transplant recipient

The number of patients receiving hematopoietic stem cell transplantation (HSCT) is rapidly rising worldwide. Despite substantial improvements in peri-transplant care, pulmonary complications resulting in respiratory failure remain a major contributor to morbidity and mortality in the post-transplant period, and represent a major barrier to the overall success of HSCT. Infectious complications include pneumonia due to bacteria, viruses, and fungi, and most commonly occur during neutropenia in the early post-transplant period. Non-infectious complications include idiopathic pneumonia syndrome, peri-engraftment respiratory distress syndrome, diffuse alveolar hemorrhage, pulmonary veno-occlusive disease, delayed pulmonary toxicity syndrome, cryptogenic organizing pneumonia, bronchiolitis obliterans syndrome, and post-transplant lymphoproliferative disorder. These complications have distinct clinical features and risk factors, occur at differing times following transplant, and contribute to morbidity and mortality.

Epstein-Barr virus post-transplant lymphoproliferative disease (PTLD) after hematopoietic stem cell transplantation

Epstein-Barr virus (EBV) viremia and post-transplant lymphoproliferative disease (PTLD) are severe complications after hematopoietic stem cell transplantation (HSCT). A series of risk factors have been found to predict EBV viremia and PTLD, including the T-cell depletion, reduced intensity conditioning, and alternative donor. The rituximab pre-emptive therapy could improve PTLD prognosis significantly, but the trigger of initiating rituximab pre-emptive therapy has not been well established. Additionally, EBV-specific cytotoxic T cell (CTL) is a promising approach to treat EBV-PTLD.

Epstein-barr virus DNAemia monitoring for the management of post-transplant lymphoproliferative disorder

BACKGROUND

Post-transplant lymphoproliferative disorder (PTLD) is a potentially fatal complication of allogeneic hematopoietic cell transplantation (HCT). Epstein-Barr virus (EBV) reactivation (detectable DNAemia) predisposes to the development of PTLD.

METHODS

We retrospectively studied 306 patients monitored for EBV DNAemia after Thymoglobulin-conditioned HCT to determine the utility of the monitoring in the management of PTLD. DNAemia was monitored weekly for ≥12 weeks post-transplantation.

RESULTS

Reactivation was detected in 82% of patients. PTLD occurred in 14% of the total patients (17% of patients with reactivation). PTLD was treated with rituximab only when and if the diagnosis was established. This allowed us to evaluate potential DNAemia thresholds for pre-emptive therapy. We suggest 100,000-500,000 IU per mL whole blood as this would result in unnecessary rituximab administration to only 4-20% of patients and near zero mortality due to PTLD. After starting rituximab (for diagnosed PTLD), sustained regression of PTLD occurred in 25/25 (100%) patients in whom DNAemia became undetectable. PTLD progressed or relapsed in 12/17 (71%) patients in whom DNAemia was persistently detectable.

DISCUSSION

In conclusion, for pre-emptive therapy of PTLD, we suggest threshold DNAemia of 100,000-500,000 IU/mL. Persistently detectable DNAemia after PTLD treatment with rituximab appears to have 71% positive predictive value and 100% negative predictive value for PTLD progression/relapse.

Rituximab-based treatments followed by adoptive cellular immunotherapy for biopsy-proven EBV-associated post-transplant lymphoproliferative disease in recipients of allogeneic hematopoietic stem cell transplantation

To improve prognosis of post-transplant lymphoproliferative disease (PTLD), a sequential therapeutic strategy that rituximab-based treatments followed by donor lymphocyte infusion (DLI) or autologous EBV-specific cytotoxic T lymphocytes (EBV-CTL) for biopsy-proven EBV-associated PTLD in recipients of allogeneic hematopoietic stem cell transplantation was designed. 84 patients with EBV-PTLD were enrolled in this prospective study. After two cycles of the rituximab-based treatments, 68 of 84 patients (81% [95% CI 71-88]) responded and 52 (62% [51-72]) had CRs. This increased to 73 of 77 patients (95% [87-98]) with completion of sequential cell infusions, and 70 of 77 (91% [82-96]) achieved CRs after DLI or autologous EBV-CTL infusion. 22 patients experienced acute GVHD (aGVHD) (grade I in 5 and grade II in 13, grade III in 4) and 13 chronic GVHD (limited cGVHD in 7 and extensive cGVHD in 6) in 62 patients undergoing a median of three doses of DLI. The incidences of GVHD were similar between DLI and EBV-CTL group (aGVHD 35% vs. 33%, p = 0.876; cGVHD 21% vs. 13%; p = 0.503). EBV-CTL activity after the rituximab-based treatments did not change, while increased after cell infusions and reached its maximum in the 3rd or 6th month after EBV-CTL or DLI treatment, respectively. The 5-y cumulative incidence of PTLD relapse was 4.5% ± 3.3%. The 5-y overall survival (OS) and progression-free survival (PFS) after PTLD were 70.7% ± 5.2% and 68.9% ± 5.3%, respectively. Rituximab-based treatments combined with adoptive cellular immunotherapy might elevate CR rates and reduce relapse of PTLD after allo-HSCT.

Is there a difference in post-transplant lymphoproliferative disorder in adults after solid organ and haematologic stem cell transplantation? Experience in 41 patients

OBJECTIVE

To determine if there is a difference in post-transplant lymphoproliferative disorder (PTLD) in adults after solid organ transplantation (SOT) and haematologic stem cell transplantation (HST).

METHODS

In this institutional review board-approved Health Insurance Portability and Accountability Act-compliant study, we reviewed clinical data and imaging at the time of diagnosis in 41 patients (26 SOT and 15 HST) (31 males and 10 females; mean age 51 years) with histopathology-confirmed PTLD seen at our institution from 2004 through 2013. Statistical analysis was performed to assess difference in distribution and survival between SOT and HST cohorts.

RESULTS

SOT: 17 lung/cardiac, 8 renal and 1 liver transplant recipients. HST: 13 leukaemia/lymphoma and 2 patients with aplastic anaemia. Median time to diagnosis: SOT 3.0 years; HST 6 months (Fisher's exact test; p = 0.0011). There was no statistically significant difference in distribution of PTLD after SOT and HST with nodes (15/26; 8/15), lung (10/26; 5/15) and bowel (6/26; 4/15) being the most common sites. Hepatic (3/26) and neurologic (2/26) involvement occurred in only SOT cohort while splenic PTLD (5/15) occurred more often in HST cohort. Death occurred earlier in HST (9/15; 2 weeks) than SOT cohort (12/26; 11 months) (Wilcoxon test; p = 0.0188).

CONCLUSION

PTLD did not differ significantly in distribution between SOT and HST cohorts. PTLD after HST occurred early and had shorter survival.

ADVANCES IN KNOWLEDGE

The most common sites of PTLD were the nodes, lung and bowel. Distribution of PTLD does not differ significantly between patients with SOT and HST. PTLD after HST occurs early and has poor survival compared with PTLD after SOT.

Very late relapse of PTLD 10 yr after allogeneic HSCT and nine yr after stopping immunosuppressive therapy

We present a very late onset relapse of PTLD 10 yr after allogeneic HSCT in a patient in third remission for ALL, nine yr after the first episode of PTLD. The recipient was conditioned with fractionated TBI 12 Gy, cyclophosphamide, and horse ATG. The first episode of PTLD with a large retroperitoneal tumor occurred one yr after transplantation; a residual tumor infiltrating spleen and colon was resected one yr later. Due to continual pathological signals in liver and lungs, persistent fever, and an M-component in peripheral blood, a new course of four rituximab doses was given, after which the fever settled, the PET scan normalized, and the M-component disappeared. Without any ongoing immunosuppressive therapy, PTLD relapsed nine yr later with large intra-abdominal lymph node masses causing ureteric obstruction with bilateral hydronephrosis. Pathological features were identical to the primary PTLD tumor: EBV related, of donor origin, positive for CD138 and CD79 alpha, but negative for CD20 and CD19. The transcription factor PAX5 was negative but BOB1 and OCT2 were positive, consistent with plasmablastic lymphoma. The relapse was successfully treated with a combination of low dose chemotherapy and rituximab. Five yr after end of treatment, the girl has moderately reduced renal function but otherwise remains well without evidence of disease.

Spectrum of Epstein-Barr virus-associated diseases in recipients of allogeneic hematopoietic stem cell transplantation

BACKGROUND

Epstein-Barr virus (EBV) infection may result in a spectrum of diseases in recipients of transplant. The aim of this study is to investigate the incidence, clinical characteristics, and prognosis of the spectrum of EBV-associated diseases in recipients of allogeneic hematopoietic stem cell transplantation (allo-HSCT).

METHODS

A total of 263 recipients undergoing allo-HSCT were prospectively enrolled. The blood EBV-DNA loads were regularly monitored by quantitative real-time polymerase chain reaction.

RESULTS

The 3-year cumulative incidence of total EBV-associated diseases, posttransplantation lymphoproliferative diseases (PTLD), EBV fever, and EBV end-organ diseases (pneumonia, encephalitis/myelitis, and hepatitis) were 15.6%±2.5%, 9.9%±2.0%, 3.3%±1.3%, and 3.3%±1.2% (2.2%±1.0%, 1.6%±0.8%, and 0.9%±0.6%), respectively. Fever was the most common symptom of EBV-associated diseases. Patients with PTLD had better response rate to rituximab-based treatments compared with those with EBV end-organ diseases (including PTLD accompanied by EBV end-organ diseases) (P=0.014). The 3-year overall survival was 37.3%±13.7%, 100.0%, and 0.0%±0.0% in patients with PTLD, EBV fever, and EBV end-organ diseases (P=0.001).

CONCLUSIONS

EBV-associated diseases other than PTLD are not rare in the recipients of allo-HSCT. The clinical manifestations of EBV end-organ diseases are similar to PTLD. EBV end-organ diseases had poorer response to rituximab-based therapy compared with PTLD.

Hemorrhagic cystitis in children treated with alkylating agent cyclophosphamide: The experience of a medical center in Taiwan

BACKGROUND/PURPOSE

Hemorrhagic cystitis is a common complication with chemotherapeutic alkylating agents. We investigated the possible prognostic factors of cyclophosphamide-induced hemorrhagic cystitis in children.

METHODS

Medical records of children (< 18 years old) with cyclophosphamide-related hemorrhagic cystitis were collected retrospectively from January 2000 to December 2010 in a tertiary care center. We also prospectively enrolled children (< 18 years old) with cyclophosphamide treatment.

RESULTS

The retrospective study consisted of 23 patients whose median age was 11 years. The median day of onset time was 1 day after cyclophosphamide usage. The hemato-oncological diseases included acute leukemia (39.1%), lymphoma (13%), blastoma (13%), sarcoma (13%), aplastic anemia (13%), and others (8.7%). Patients who received bone marrow transplantation (BMT) had significantly longer duration of hemorrhagic cystitis than those who did not receive BMT (p < 0.05). Serum uric acid, checked prior to and after the onset of hemorrhage cystitis, was significantly lower after the development of hemorrhagic cystitis (p < 0.05). In the prospective study, 11 children were enrolled with a median age of 5 years. The urinary nitrite/nitrate and 8-iso-prostaglandin F2α levels increased significantly after cyclophosphamide usage (p < 0.05).

CONCLUSION

Alteration serum uric acid level and BMT could be indicators for severe hemorrhagic cystitis. The elevated levels of urinary nitrite/nitrate and 8-iso-prostaglandin F2α may indicate the essential roles played by nitric oxide syntheses and reactive oxidative stress in cyclophosphamide-induced hemorrhagic cystitis. These findings may help clinicians formulate a better strategy for treating cyclophosphamide-induced hemorrhagic cystitis.

EBV-induced post transplant lymphoproliferative disorders: a persisting challenge in allogeneic hematopoetic SCT

EBV-induced post transplantation lymphoproliferative disorder (EBV-PTLD) is a life-threatening complication after allogeneic hematopoietic cell transplantation. Profound T-cell depletion of the allograft represents a major risk factor for EBV-PTLD. With regard to the increasing use of alternative stem cell sources such as cord blood or purified haploidentical stem cell grafts both associated with impaired immune reconstitution, the frequent occurrence of EBV-PTLD demands particular vigilance on laboratory changes and early symptoms. Here we have summarized today's knowledge about EBV-PTLD in a comprehensive review explaining the underlying mechanisms of EBV-based transformation, EBV-PTLD development, clinical presentation, incidence, diagnosis, screening, therapy and prognosis. In this context, we emphasize on the necessity of regularly applied screening tools and pre-emptive treatment strategies including anti-CD20 Abs particularly in high-risk patients to avoid disease progression to malignant lymphoma. Although EBV-PTLD has always been associated with a high mortality rate, novel immunotherapeutic approaches such as the transfer of EBV-specific T cells nowadays offer improved chances of disease control even at late stages.

Molecular monitoring and stepwise preemptive therapy for Epstein-Barr virus viremia after allogeneic stem cell transplantation

The optimal preemptive therapy for Epstein-Barr virus (EBV)-associated diseases remains under discussion. We developed a stepwise preemptive therapy (antiviral agents and reduction of immunosuppressants [RI] followed by rituximab) for EBV viremia, based on duration of EBV viremia and changes of viral loads. The blood EBV-DNA loads were regularly monitored by quantitative real-time polymerase chain reaction in 251 recipients undergoing allogeneic stem cell transplantation. The 3-year cumulative incidence of EBV viremia and EBV-associated diseases were 31.1% ± 3.1% and 15.6% ± 2.5%, which rose steeply with greater numbers of major risk factors. Of the 64 patients undergoing first-step preemption, 24 achieved complete response (CR) and 40 showed no response, including 25 progressing to EBV-associated diseases. The effective rates of antiviral agents and RI plus antiviral agents were 2/16 and 22/48 (P = 0.017). Fourteen achieved CR and one progressed to lymphoproliferative disease in the 15 patients undergoing rituximab preemption. Of the 26 patients progressing to EBV-associated diseases during preemptive therapy, 20 obtained CR in the 23 cases with rituximab-based treatments. The preemptive efficacy of RI plus antiviral agents was correlated with the numbers of major risk factors (rs  = -0.298; P = 0.04). B-cell reconstitution was significantly delayed for at least 6 months in patients with rituximab preemption. The risk of herpesvirus infection was similar in patients who showed effective progress to first-step and rituximab preemption (P = 0.094). RI plus antiviral agents could be given priority to low-risk patients, whereas more frequent monitoring of blood EBV-DNA and earlier preemptive rituximab should be advocated in high-risk patients.

Pre-emptive rituximab based on viraemia and T cell reconstitution: a highly effective strategy for the prevention of Epstein-Barr virus-associated lymphoproliferative disease following stem cell transplantation

This study investigated the efficacy of a pre-emptive strategy based on the combination of Epstein-Barr virus (EBV) viraemia and poor T cell reconstitution in preventing post-transplant lymphoproliferative disease (PTLD) following T cell depleted stem cell transplant (SCT). EBV viral load and immune reconstitution were prospectively monitored in 70 consecutive children undergoing SCT following reduced intensity conditioning with alemtuzumab. Patients who developed significant EBV viraemia (> 40 000 copies/ml blood) were treated pre-emptively with rituximab if they were within 3 months of SCT or their CD3 count was <0·3 × 10⁹ /l. Of 20/70 patients who developed significant EBV viraemia, 13 received pre-emptive rituximab. The incidence of PTLD was significantly reduced in the pre-emptive cohort compared to historical controls (1·4% vs. 21·7%, P = 0·003). This difference was more marked among viraemic patients (2·7% vs. 62·5%P < 0·0001). Patients treated with rituximab demonstrated significantly delayed B cell reconstitution at 1 year post-SCT but this was not associated with an increase in infectious mortality. In 6/6 patients >3 months post-SCT who had a CD3 count >0·3 × 10⁹ /l, reduced immunosuppression only resulted in successful resolution of EBV viraemia without PTLD. This strategy is safe and highly effective in preventing PTLD following T cell depleted SCT, and directs rituximab therapy to patients at highest risk of this complication.

[Transplant-associated lymphoproliferation]

Transplantation of solid organs and haematopoietic stem cells requires immunosuppressive drug therapy in order to prevent rejection or graft-versus-host disease. Depending on dosage and type of drug, the risk of developing an Epstein-Barr virus (EBV)-associated post-transplant lymphoproliferative disease (PTLD) is increased. The lesion spectrum ranges from hyperplastic lesions to manifest lymphomas, the latter being classified as monomorphic PTLD. Hyperplastic changes, which are not distinguishable from viral reactions, comprise early or mononucleosis-like lesions. Those with effaced lymph node architecture or extranodal manifestation without a lymphoma-like phenotype are designated polymorphic PTLD. Monomorphic PTLD are either high grade B cell lymphomas, plasma cell neoplasms or Hodgkin lymphomas and only very rarely T cell lymphomas. Low grade B cell lymphomas do not occur. In a subfraction of cases, including even monomorphic PTLD, reduction of immunosuppression alone is sufficient to induce remission of the pathological process.

An official American Thoracic Society research statement: noninfectious lung injury after hematopoietic stem cell transplantation: idiopathic pneumonia syndrome

RATIONALE

Acute lung dysfunction of noninfectious etiology, known as idiopathic pneumonia syndrome (IPS), is a severe complication following hematopoietic stem cell transplantation (HSCT). Several mouse models have been recently developed to determine the underlying causes of IPS. A cohesive interpretation of experimental data and their relationship to the findings of clinical research studies in humans is needed to better understand the basis for current and future clinical trials for the prevention/treatment of IPS.

OBJECTIVES

Our goal was to perform a comprehensive review of the preclinical (i.e., murine models) and clinical research on IPS.

METHODS

An ATS committee performed PubMed and OVID searches for published, peer-reviewed articles using the keywords "idiopathic pneumonia syndrome" or "lung injury" or "pulmonary complications" AND "bone marrow transplant" or "hematopoietic stem cell transplant." No specific inclusion or exclusion criteria were determined a priori for this review.

MEASUREMENTS AND MAIN RESULTS

Experimental models that reproduce the various patterns of lung injury observed after HSCT have identified that both soluble and cellular inflammatory mediators contribute to the inflammation engendered during the development of IPS. To date, 10 preclinical murine models of the IPS spectrum have been established using various donor and host strain combinations used to study graft-versus-host disease (GVHD). This, as well as the demonstrated T cell dependency of IPS development in these models, supports the concept that the lung is a target of immune-mediated attack after HSCT. The most developed therapeutic strategy for IPS involves blocking TNF signaling with etanercept, which is currently being evaluated in clinical trials.

CONCLUSIONS

IPS remains a frequently fatal complication that limits the broader use of allogeneic HSCT as a successful treatment modality. Faced with the clinical syndrome of IPS, one can categorize the disease entity with the appropriate tools, although cases of unclassifiable IPS will remain. Significant research efforts have resulted in a paradigm shift away from identifying noninfectious lung injury after HSCT solely as an idiopathic clinical syndrome and toward understanding IPS as a process involving aspects of both the adaptive and the innate immune response. Importantly, new laboratory insights are currently being translated to the clinic and will likely prove important to the development of future strategies to prevent or treat this serious disorder.

High incidence of post transplant lymphoproliferative disorder after antithymocyte globulin-based conditioning and ineffective prediction by day 28 EBV-specific T lymphocyte counts

The largest study on post-allogeneic hematopoietic cell transplant lymphoproliferative disorder (PTLD) epidemiology showed a cumulative incidence of 1.7% in patients receiving antithymocyte globulin (ATG). We had noted an apparently higher incidence in our transplant recipients whose conditioning included ATG. Therefore, we formally determined the incidence of PTLD through chart review. We also evaluated whether counts of EBV-specific T lymphocytes measured by cytokine flow cytometry could identify patients at risk of developing PTLD. Among 307 allogeneic transplant recipients, 25 (8.1%) developed PTLD. This was biopsy proven in 11 patients, and was fatal in seven patients. Patient age, EBV serostatus, donor type/match or GVHD did not influence PTLD risk significantly. Median onset of PTLD was 55 (range, 28-770) days post transplant. Day 28 EBV-specific T lymphocyte counts were not significantly different in 11 patients who developed PTLD and 31 non-PTLD patients matched for published risk factors for PTLD. In summary, when using conditioning with thymoglobulin 4.5 mg/kg, the incidence of PTLD is relatively high and cannot be predicted by day 28 cytokine flow cytometry-determined EBV-specific T lymphocyte counts. Thus, in this scenario PTLD prevention may be warranted, for example, using EBV DNAemia monitoring with preemptive therapy.

Clinical characteristics of monomorphic post-transplant lymphoproliferative disorders

Post-transplant lymphoproliferative disorders (PTLD) are a heterogeneous group of lymphoproliferative disorders associated with immunosuppression and Epstein-Barr virus infection. PTLD is classified into three major categories: early lesions, polymorphic PTLD, and monomorphic PTLD. The majority of monomorphic PTLD cases are non-Hodgkin's lymphoma of B-cell origin. This retrospective study was conducted to investigate the incidence, clinical manifestation, treatment, and outcomes of monomorphic PTLD among 5,817 recipients of solid organ or allogeneic hematopoietic stem cell transplantation from five institutions. Fourteen patients with monomorphic PTLD were identified (male:female 11:3; median age 42.6 yr, range 24-60). The overall incidence rate was 0.24%. The most common disease type was diffuse large B cell lymphoma (n=7). The median time between the transplant and diagnosis of PTLD was 85.8 months. However, all cases of PTLD after allogeneic hematopoietic stem cell transplantation occurred within 1 yr after transplantation. Ten of the 14 patients had EBV-positive tumor. Fourteen patients received combination systemic chemotherapy and four patients were treated with radiation therapy. Ten patients achieved a complete response (CR) and two patients a partial response (PR). The median follow-up period for surviving patients was 36.6 months. Nine patients remain alive (eight CR, one PR). Nine of 11 solid organ transplantations preserved graft function. The present study indicates a lower incidence rate and a longer median time before the development of PTLD than those of previous reports. Careful monitoring was needed after allogeneic hematopoietic stem cell transplantation for PTLD.

Phase-1 study of siplizumab in the treatment of pediatric patients with at least grade II newly diagnosed acute graft-versus-host disease

In a phase-1 study, siplizumab, a humanized anti-CD2 monoclonal antibody, was administered (0.012 or 0.04 mg/kg) to 10 pediatric patients with > or = grade-II newly diagnosed, non-steroid-refractory aGvHD after BMT or PBSCT. SAEs and other AEs including infections, and GvHD staging changes (overall, skin, liver, gut) were evaluated over 364 days. Patients reported a total of 121 AEs (19 grade-3, 5 grade-4 0.012 mg/kg group; 17 grade-3, 17 grade-4 0.04 mg/kg group) and 14 SAEs (five grade-3, three grade-4, 0.012 mg/kg group; three grade-3, 0.04 mg/kg group); 15 AEs in five patients and four SAEs in three patients (fever, PTLD, adenoviral infection, and EBV lymphoma) were considered siplizumab-related. Six deaths occurred (study days 17-267); two were considered siplizumab-related: one from EBV-associated PTLD (0.012 mg/kg) and one from adenoviral infection (0.04 mg/kg); the other four deaths could potentially be attributed in part to study drug Three patients (one, 0.012 mg/kg group; two, 0.04 mg/kg group) developed PTLD. By study day 12, GvHD grade decreased in 3/5 and 2/5 patients in the 0.012 and 0.04 mg/kg groups, respectively; remission (grade 0) occurred in one patient in each group. Four of five patients (0.012 mg/kg group) and one of four patients (0.04 mg/kg group) achieved grade 0 GvHD during the first 100 study days (55.6% response). While treatment with siplizumab was associated with improvement of GvHD and remission in some pediatric patients, the overall high morbidity, mortality, and occurrence of PTLD is of safety concern, not warranting further development of siplizumab for the treatment of aGvHD in children.

A novel haplo-identical adoptive CTL therapy as a treatment for EBV-associated lymphoma after stem cell transplantation

Epstein-Barr virus (EBV)-related malignancies such as post-transplant lymphoproliferative disease (PTLD) are severe complications after allogeneic stem cell transplantation and solid-organ transplantation. In immunosuppressed transplant recipients, the activity of EBV-specific CTLs are often decreased or absent which leads to an increased risk of developing PTLD. If primary treatment modalities of PTLD fail, the most efficient way of treating the malignancy is adopting EBV-specific CTLs from the donor or, more recently, third-party donors. However, both are time consuming and expensive and often it is too late to administer cells to the patient. We have for the first time, using a rapid isolation protocol of EBV-specific T cells, treated and cured a patient suffering from PTLD with multiple-associated tissue lesions, using her haplo-identical mother as a donor. This treatment approach paves way for a new possibility to within-days treat patients with life-threatening EBV-associated malignancies.

Imaging findings in immunosuppressed patients with Epstein Barr virus-related B cell malignant lymphoma

OBJECTIVE

The purpose of this study was to describe multimodality imaging findings in immunosuppressed patients with Epstein-Barr virus (EBV)-related malignant lymphoproliferative diseases.

CONCLUSION

EBV-related malignant lymphoproliferative diseases share common features with other aggressive lymphomas, including a high degree of extranodal involvement, tumor vascularization, and tumor necrosis. Cognizance of the particular underlying diseases and conditions associated with the development of EBV-related lymphoproliferative diseases and associated imaging results should provide more accurate diagnosis.

Donor-derived second hematologic malignancies after cord blood transplantation

Double umbilical cord blood transplantation (UCBT) with a reduced-intensity conditioning regimen is an effective strategy for adult patients without a matched donor. The risk of second malignancies in these patients has not yet been established, however. In the present study, 98 adults with a hematologic malignancy underwent double UCBT. Seventy patients received a reduced-intensity conditioning regimen of fludarabine 30 mg/m(2)/day for 6 days, melphalan 100 mg/m(2)/day for 1 day, and rabbit antithymocyte globulin 1.5 mg/kg/day for 4 days, and 28 patients received a myeloablative total body radiation-containing conditioning regimen. Sixty-three patients received sirolimus-based graft-versus-host disease (GVHD) prophylaxis, and 35 patients received non-sirolimus-based GVHD prophylaxis. The median patient age was 48 years (range, 19-67 years). Eighteen patients developed a second malignancy at a median of 134 days after transplantation. Sixteen patients had lymphoma, and 2 patients had myelodysplasic syndrome/myeloproliferative disorder (MDS/MPD). Sixteen of these second malignancies (both cases of MDS/MPD and 14 of the lymphomas) were donor-derived; the origins of the others were not determined. GVHD prophylaxis, HLA matching, primary disease, age, total nucleated cell dose, and CD34(+) cell dose were not associated with a higher rate of second malignancy. Second myelogenous malignancies of donor origin occur after double UCBT, suggesting that a search for donor origin should be performed in all patients with suspected relapse.

Endobronchial Epstein-Barr Virus Associated Post-transplant Lymphoproliferative Disorder in Hematopoietic Stem Cell Transplantation

The Epstein-Barr virus (EBV) associated Post-Transplant Lymphoproliferative Disorders (PTLD) are increasingly recognized as a fatal complication of hematological stem cell transplantation (HSCT). Thoracic involvement, that may be isolated or part of a disseminated disease, usually encompasses pulmonary nodules or masses and mediastinal lymph node enlargement.

The current case study presents 2 patients who underwent HSCT, one allogenic and the other autologous, who developed an exceptional endobronchial EBV related PTLD. The first patient had a fleshy white endobronchial mass resulting in a right upper lobe atelectasis and the second had an extensive necrotising mucosa from trachea to both basal bronchi without any significant change of lung parenchyma on the CT scan. In both cases, the diagnosis was made by bronchial biopsies. Physicians should be aware of an endobronchial pattern of EBV associated PTLD after HSCT to permit quick diagnosis and therapeutic intervention.