The clinicopathologic spectrum of posttransplantation lymphoproliferative disorders

Mechanistic Understanding of EBV+Lymphoproliferative Disease Development After Transplantation

Posttransplant lymphoproliferative disorders (PTLDs) are among the most common malignant complications after transplantation, leading to a drastic reduction in patient survival rates. The majority of PTLDs are tightly linked to Epstein-Barr virus (EBV+PTLDs) and are the result of an uncontrolled proliferation of EBV-infected cells. However, although EBV infections are a common finding in transplant recipients, most patients with high EBV loads will never develop EBV+PTLD. Natural killer cells and EBV-specific CD8+ T lymphocytes are critical for controlling EBV-infected cells, and the impairment of these cytotoxic immune responses facilitates the unfettered proliferation of EBV-infected cells. Recent years have seen a considerable increase in available literature aiming to describe novel risk factors associated with the development of EBV+PTLD, which may critically relate to the strength of EBV-specific natural killer cell and EBV-CD8+ T lymphocyte responses. The accumulation of risk factors and the increased risk of developing EBV+PTLD go hand in hand. On the one hand, most of these risk factors, such as the level of immunosuppression or the EBV donor and recipient serologic mismatch, and distinct genetic risk factors are host related and affect cytotoxic EBV-specific immune responses. On the other hand, there is growing evidence that distinct EBV variants may have an increased malignant potential and are thus more likely to induce EBV+PTLD. Here, we aim to review, from a mechanistic point of view, the risk factors for EBV+PTLD in the host and the infecting EBV variants that may explain why only a minority of transplant recipients develop EBV+PTLD.

Post-transplant lymphoproliferative disorder associated Epstein-Barr virus DNAemia after liver transplantation in children: Experience from single center

The most prevalent malignancy that complicates both adult and pediatric solid organ transplantation is post-transplant lymphoproliferative disorder (PTLD). This study aimed to analyze the clinical and pathological characteristics, treatments, and outcomes of Epstein-Barr virus (EBV) DNAemia and PTLD in pediatric liver transplant recipients. A retrospective chart review was performed on 112 patients less than 18 years of age who underwent isolated orthotopic liver transplantation (OLT) between 2010 and 2022 at Ege University Children's Hospital. Data gathered for 1-year post-OLT included age at OLT, EBV, immunoglobulin (Ig)M/IgG status of the donor and recipient, indication for OLT, induction regimen, all immunosuppression levels, date and result of EBV polymerase chain reaction testing, rejection episodes documented by liver biopsy, and the development of PTLD. Forty-nine patients (43.75%) developed EBV DNAemia (median interval from surgery: 2 months, min-max: 2-36), of which 43 (87.8%) grafts came from living donors, and 6 (12.2%) came from deceased donors. Nine (18.4%) patients died during follow-up, and eight (16.3%) developed PTLD. Of these 8 patients; five patients developed EBV-related disease, one child developed hemophagocytic lymphohistiocytosis, one developed aplastic anemia, and one child developed B cell lymphoma. When PTLD patients and without-PTLD patients were compared, pediatric intensive care unit hospitalization, abnormal bone marrow biopsy findings, lymphadenopathy, age at diagnosis of EBV DNAemia, EBV viral load, tacrolimus (FK 506) pre-infection, were higher and tacrolimus 1-month levels were lower in patients with PTLD (p < 0.05). In logistic regression analysis, we showed that the age at diagnosis of EBV DNAemia was significantly higher in children with PTLD (p = 0.045; OR: 1.389; 95% CI: 1.007-1.914). PTLD is a rare but severe complication associated with EBV after OLT. This study demonstrated that PTLD is associated with older age, higher tacrolimus blood levels before EBV DNAemia, and higher peak EBV viral load at 1 month of EBV DNAemia.

The pathobiology of select adolescent young adult lymphomas

Lymphoid cancers are among the most frequent cancers diagnosed in adolescents and young adults (AYA), ranging from approximately 30%-35% of cancer diagnoses in adolescent patients (age 10-19) to approximately 10% in patients aged 30-39 years. Moreover, the specific distribution of lymphoid cancer types varies by age with substantial shifts in the subtype distributions between pediatric, AYA, adult, and older adult patients. Currently, biology studies specific to AYA lymphomas are rare and therefore insight into age-related pathogenesis is incomplete. This review focuses on the paradigmatic epidemiology and pathogenesis of select lymphomas, occurring in the AYA patient population. With the example of posttransplant lymphoproliferative disorders, nodular lymphocyte-predominant Hodgkin lymphoma, follicular lymphoma (incl. pediatric-type follicular lymphoma), and mediastinal lymphomas (incl. classic Hodgkin lymphoma, primary mediastinal large B cell lymphoma and mediastinal gray zone lymphoma), we here illustrate the current state-of-the-art in lymphoma classification, recent molecular insights including genomics, and translational opportunities. To improve outcome and quality of life, international collaboration in consortia dedicated to AYA lymphoma is needed to overcome challenges related to siloed biospecimens and data collections as well as to develop studies designed specifically for this unique population.

Post-transplant lymphoproliferative disorders (PTLD) in adolescents and young adults: A category in need of definition

Post-transplant lymphoproliferative disorders are a well-recognized complication of solid organ and stem cell transplantation. Much data has accumulated with respect to the pathobiology and clinical behavior of these lesions in the general post-transplant population as well as in the pediatric and adult age groups. However, information as to these lesions in the adolescent and young adult populations, which bridge the pediatric and adult groups, is limited. In this review, the focus is on this unique population of PTLD patients and their proliferations.

Recent Advances in Adult Post-Transplant Lymphoproliferative Disorder

PTLD is a rare but severe complication of hematopoietic or solid organ transplant recipients, with variable incidence and timing of occurrence depending on different patient-, therapy-, and transplant-related factors. The pathogenesis of PTLD is complex, with most cases of early PLTD having a strong association with Epstein-Barr virus (EBV) infection and the iatrogenic, immunosuppression-related decrease in T-cell immune surveillance. Without appropriate T-cell response, EBV-infected B cells persist and proliferate, resulting in malignant transformation. Classification is based on the histologic subtype and ranges from nondestructive hyperplasias to monoclonal aggressive lymphomas, with the most common subtype being diffuse large B-cell lymphoma-like PTLD. Management focuses on prevention of PTLD development, as well as therapy for active disease. Treatment is largely based on the histologic subtype. However, given lack of clinical trials providing evidence-based data on PLTD therapy-related outcomes, there are no specific management guidelines. In this review, we discuss the pathogenesis, histologic classification, and risk factors of PTLD. We further focus on common preventive and frontline treatment modalities, as well as describe the application of novel therapies for PLTD and elaborate on potential challenges in therapy.

Survival of Post-Transplant Lymphoproliferative Disorder after Kidney Transplantation in Patients under Rapamycin Treatment

Background: One of the important causes of mortality and morbidity in kidney transplanted patients is Post Transplant Lymphoproliferative Disease (PTLD), which is due to immunosuppression therapy and viral activity. It seems that Rapamycin, with dual antineoplastic and immunosuppressive effects, may have a pivotal role in the treatment of PTLD patients and preserving transplanted kidneys.

Methods and Materials: Twenty patients with PTLD were enrolled. Immunosuppressive therapy was reduced or ceased, and Rapamycin was initiated at the time of PTLD diagnosis. We evaluated the effects of switching immunosuppressive drugs to Rapamycin on graft status, the response of tumor, and 6, 12 months, and 5-year survival in patients.

Results: PTLD remission was achieved in 14 patients, while six patients died; no relapse was detected in recovered patients. The median of PTLD free time was 25 months, and the mean overall survival in patients with PTLD treated by Rapamycin was 84.8 (95% CI=61.3-108.23).The five-year survival rate was 67%, 12 months survival was 73.8%, and six months' survival was 80%. The response rate to Rapamycin and immunosuppression reduction alone was 46.6%. Four out of 13 Diffuse Large B-Cell Lymphoma patients achieved a complete response just only after the reduction of immunosuppressive drugs and the consumption of Rapamycin.

Conclusion: The present study demonstrated the effectiveness of conversion from immunosuppressive medication, particularly of Calcineurin inhibitors to Rapamycin in PTLD patients. However, more research is needed to confirm the Rapamycin effect on patients with PTLD.

Risk factors evaluation of post-transplant lymphoproliferative disorders after allogeneic haematopoietic stem cell transplantation with comparison between paediatric and adult

To describe the clincopathological features and evaluate risk factors of post-transplant lymphoproliferative disorder (PTLD) after allogeneic haematopoietic stem cell transplants (allo-HSCT), with comparison between paediatric and adult .Clinicopathological features of 81 cases of PTLD after allo-HSCT were analysed by histopatholgy, immunohistochemistry and in situ hybridisatioin.The cases included 58 males and 23 females with a median age of 26.7 years (range 6-55 years) and the PTLDs developed 1-60 months post-transplant (mean 5.9 months). The histological types indicated 10 cases of non-destructive PTLD, including 4 of plasmacytic hyperplasia, 5 of infectious mononucleosis and 1 of florid follicular hyperplasia. Fifty-six cases were polymorphic PTLD, and 15 were monomorphic PTLD, including thirteen of diffuse large B cell lymphoma, 1 of extranodal nasal type natural killer (NK)/T cell lymphoma and 1 of plasmablastic lymphoma. Foci and sheets of necrosis were observed in 31 cases. The infected ratio of Epstein-Barr virus (EBV) was 91.4%. Some cases were treated by reduction of immunosuppression, antiviral therapy, donor lymphocyte infusion or anti-CD20 monoclonal rituximab. Thirty-three cases died. Compared with that of adult, overall survival of paediatric recipient may be better.The first half year after allo-HSCT is very important for the development of PTLD. Type of PTLD, EBV infection and graft-versus-host disease are risk factors. The prognosis of PTLD is poor, and PTLD after allo-HSCT exhibits some features different from that after solid organ transplantation and some differences existing between adult and paediatric recipients.

Transplantation for congenital heart disease is associated with an increased risk of Epstein-Barr virus-related post-transplant lymphoproliferative disorder in children

BACKGROUND

Children undergoing heart transplant are at higher risk of developing post-transplant lymphoproliferative disorder (PTLD) than other solid organ recipients. The factors driving that risk are unclear. This study investigated risk factors for PTLD in children transplanted at 1 of 2 United Kingdom pediatric cardiac transplantation centers.

METHODS

All children (<18 years, n = 200) transplanted at our institution over a 16-year period were analyzed. Freedom from PTLD was assessed using the Kaplan-Meier method and Cox proportional regression.

RESULTS

PTLD occurred in 17 of 71 children transplanted for congenital heart disease (CHD) and 18 of 129 transplanted for acquired cardiomyopathy (ACM). The cumulative incidence of all PTLD was 21.1% at 5 years after transplant. Median time from transplant to PTLD was 2.9 years (interquartile range: 0.9-4.6). Negative Epstein-Barr virus (EBV) serostatus pre-transplant (adjusted hazard ratio [HR]: 2.7, 95% CI: 1.3-5.6, p = 0.01) and underlying CHD (adjusted HR: 3.2, 95% CI: 1.4-7.4, p = 0.007) were independently associated with higher risk of PTLD. Age at thymectomy was significantly different between children with CHD and ACM (0.4 vs 5.5 years, p < 0.01). Median CD4⁺ and CD8⁺ T lymphocyte counts at 2 years after transplant were significantly lower in children transplanted for CHD vs ACM (CD4⁺: 391/µl vs 644/µl, p = 0.01; CD8⁺: 382/µl vs 500/µl, p = 0.01). At 5 years after transplant, those differences persisted among patients who developed PTLD (CD4⁺, 430/µl vs 963/µl, p < 0.01 and CD8⁺, 367/µl vs 765/µl, p < 0.01).

CONCLUSION

Underlying CHD is an independent risk factor for PTLD and is associated with a younger age at thymectomy. A persistent association with altered T lymphocyte subsets may contribute to the impaired response to primary EBV infection and increase the risk of PTLD.

Biological Difference Between Epstein-Barr Virus Positive and Negative Post-transplant Lymphoproliferative Disorders and Their Clinical Impact

Epstein–Barr virus (EBV) infection is correlated with several lymphoproliferative disorders, including Hodgkin disease, Burkitt lymphoma, diffuse large B-cell lymphoma (DLBCL), and post-transplant lymphoproliferative disorder (PTLD). The oncogenic EBV is present in 80% of PTLD. EBV infection influences immune response and has a causative role in the oncogenic transformation of lymphocytes. The development of PTLD is the consequence of an imbalance between immunosurveillance and immunosuppression. Different approaches have been proposed to treat this disorder, including suppression of the EBV viral load, reduction of immune suppression, and malignant clone destruction. In some cases, upfront chemotherapy offers better and durable clinical responses. In this work, we elucidate the clinicopathological and molecular-genetic characteristics of PTLD to clarify the biological differences of EBV(+) and EBV(–) PTLD. Gene expression profiling, next-generation sequencing, and microRNA profiles have recently provided many data that explore PTLD pathogenic mechanisms and identify potential therapeutic targets. This article aims to explore new insights into clinical behavior and pathogenesis of EBV(–)/(+) PTLD with the hope to support future therapeutic studies.

Long-term exposure to air pollution and risk of non-Hodgkin lymphoma in Denmark: A population-based case-control study

There is limited evidence regarding a possible association between exposure to ambient air pollutants and the risk of non-Hodgkin lymphoma (NHL). Previous epidemiological studies have relied on crude estimations for air pollution exposure and/or small numbers of NHL cases. The objective of our study was to analyze this association based on air pollution modeled at the address level and NHL cases identified from the nationwide Danish Cancer Registry. We identified 20,874 incident NHL cases diagnosed between 1989 and 2014 and randomly selected 41,749 controls matched on age and gender among the entire Danish population. We used conditional logistic regression to estimate odds ratios (ORs) and adjusted for individual and neighborhood level sociodemographic variables. There was no association between exposure to PM_2.5 , BC, O₃ , SO₂ or NO₂ and overall risk of NHL but several air pollutants were associated with higher risk of follicular lymphoma, but statistically insignificant, for example, PM_2.5 (OR = 1.15 per 5 μg/m³ ; 95% CI: 0.98-1.34) and lower risk for diffuse large B-cell lymphoma (OR = 0.92 per 5 μg/m³ ; 95% CI: 0.82-1.03). In this population-based study, we did not observe any convincing evidence of a higher overall risk for NHL with higher exposure to ambient air pollutants.

Epithelial to mesenchymal transition in endomyocardial biopsies from orthotopic heart transplant recipients

Epithelial to mesenchymal transition (EMT) occurs when cells lose morphological features of epithelial cells, such as cell-to-cell adhesion, and gain features of mesenchymal cells, including elongation and flattening. These cells also lose expression of epithelial immunohistochemical markers. In this report, we present a 55-year-old Caucasian male patient who underwent orthotopic heart transplant and immunosuppressant therapy with tacrolimus and mycophenolic acid. Seven and a half months later, an endomyocardial biopsy revealed a hypercellular, atypical lesion. Evaluation was negative for acute cellular rejection and post-transplant lymphoproliferative disorder. Histopathologic features and immunohistochemical stains were consistent with EMT. We subsequently identified four additional cases of EMT in patients who underwent orthotopic heart transplantation and received a similar immune suppression regimen. EMTs have been reported to occur in lung and kidney allografts; however, this is the first known report describing this entity in a heart transplant recipient.

Post-transplant lymphoproliferative disorder presenting as T-prolymphocytic leukemia: a case report

Introduction

Post-transplant lymphoproliferative disorder is a serious disorder which occurs post hematopoietic stem cell transplant or solid organ transplantation. T-prolymphocytic leukemia is a T cell type monomorphic post-transplant lymphoproliferative disorder which accounts for only 2% of all mature lymphocytic leukemias in adults over the age of 30.

Case presentation

A 59-year-old man of Chinese ethnicity presented to our hematology unit with headache, lethargy, and exertional dyspnea for the past 1 month. He underwent an uneventful cadaveric renal transplant 20 years ago for chronic glomerulonephritis-induced end-stage renal disease. He had been on long-term immunosuppressants since then consisting of orally administered prednisolone 10 mg daily and orally administered cyclosporine A 50 mg twice daily. On examination, he was pale with a palpable liver and spleen. He had a functioning renal graft. Marrow flow cytometry confirmed T-prolymphocytic leukemia with lymphocytes expressing CD2, CD3, CD7, CD52, and TCL-1. His human T-cell lymphotropic virus and Epstein–Barr virus serology and deoxyribonucleic acid (DNA) were negative. He was treated with one cycle of cyclophosphamide, doxorubicin, vincristine, and prednisone chemotherapy to which he failed to respond. In view of his renal allograft, he was not suitable for alemtuzumab due to the risk of nephrotoxicity. He was given orally administered venetoclax but he died on day 17 due to severe auto tumor lysis syndrome.

Conclusion

The place of immunophenotyping in the diagnosis and treatment of this disorder is of significant importance. More research needs to be carried out to further comprehend the pathophysiology and treatment modalities for this disorder.

Very late onset post-transplant diffuse large B cell lymphoma in a liver transplant recipient with hepatitis B: A case report

RATIONALE

Post transplantation lymphoproliferative disorder (PTLD) is a rare but severe complication. Epstein-Barr virus (EBV) is considered an important pathogen for PTLD and EBV deoxyribonucleic acid (DNA) load is widely monitored to detect PTLD early. Hepatitis B virus (HBV) infection is rarely reported to be related with PTLD. We report a case of EBV negative (EBV), HBV positive (HBV) diffuse large B cell lymphoma in a patient 12 years after liver transplantation.

PATIENT CONCERNS AND DIAGNOSIS

A 52-year-old man complained of worsening appetite, abdominal distension, and pruritus. Abdominal computed tomography (CT) detected a huge retroperitoneal mass and pathology of the fine needle biopsy established the diagnosis of diffuse large B cell lymphoma. Virology showed active hepatitis B viral duplication and EBV DNA was negative.

INTERVENTION

Treatment modalities for this patient included: reduction and subsequent cessation of immunosuppression; antiviral therapy for HBV with entecavir and adefovir; conventional chemotherapy consisting of cyclophosphamide, epirubicin, vindesine, and prednisone, followed by radiotherapy. He achieved complete remission (CR) and was kept on entecavir treatment afterwards.

OUTCOMES

He has been in remission for 2 years.

LESSONS

HBV infection might have played some role in this very late onset EBV PTLD patient. Therefore, HBV serology and HBV load should be monitored during the follow-up of HBV surface antigen positive (HBsAg) transplant recipients and life-long antiviral therapy is required.

A single-center experience of post-transplant lymphoproliferative disorder (PTLD) cases after pediatric liver transplantation: Incidence, outcomes, and association with food allergy

BACKGROUND/AIMS

We evaluated our 16-year single-center experience of pediatric post-transplant lymphoproliferative disorder (PTLD) cases who underwent liver transplantation between 2001 and 2017.

MATERIALS AND METHODS

Of the 236 pediatric patients who underwent liver transplantation between 2001 and 2017, the clinical and laboratory data of eight patients diagnosed with PTLD were reviewed. The pre-transplant Epstein-Barr virus (EBV) status of 172 patients was also recorded.

RESULTS

The total incidence of PTLD was 3.4%. The incidence of PTLD was 10% in pre-transplant EBV immunoglobulin G (IgG)-seronegative patients and 0.8% in pre-transplant EBV IgG-seropositive patients. The mean age of the patients at liver transplantation was 2.71±3.21 years, and four patients were aged below 1 year at the time of transplantation. PTLD was diagnosed at 21.81±18.1 months after transplantation. The primary site of involvement was variable among patients: peripheral and mediastinal lymph nodes, stomach and intestine, transplanted graft, bone marrow, and nasopharynx. The eosinophil count varied greatly among patients, with a mean value of 524.62±679/mm3. Three patients had a food allergy and were administered an elimination diet at the time of PTLD diagnosis. Six patients had PTLD of B-cell origin. One patient died due to neutropenic sepsis during chemotherapy, whereas seven patients were followed up in full remission for 7.75±4 years.

CONCLUSION

PTLD is a life-threatening complication of solid-organ transplantation with a heterogeneous clinical spectrum. Food allergy had a close association with PTLD. A close follow-up of patients with risk factors and an early diagnosis with appropriate treatment may lead to a better outcome.

Post-transplant lymphoproliferative disorders after solid organ and hematopoietic stem cell transplantation

Post-transplant lymphoproliferative disorders (PTLD) are a rare complication after both solid organ (SOT) and allogeneic hematopoietic stem cell transplantation (allo-HSCT). In this single center retrospective study, we compared clinical, biological, and histological features, and outcomes of PTLD after both types of transplant. We identified 82 PTLD (61 after SOT and 21 after allo-HSCT). The presence of B symptoms, Waldeyer ring, spleen, central nervous system, and liver involvement, and advanced Ann-Arbor stage were more frequent in allo-HSCT recipients. PTLD had an earlier onset in allo-HSCT than in SOT cohort (4 vs. 64 months, p < .0001). PTLD was EBV-positive in 100% of allo-HSCT, in contrast to 47% of SOT (p = .0002). Four years after PTLD diagnosis, median overall survival was 32% (95% CI, 22-48) and 10% (95% CI, 2-49) in SOT and allo-HSCT recipients, respectively (p = .002). In conclusion, the clinical presentation and the outcome of PTLD varies greatly depending on the type of transplant.

Acute Kidney Injury in Transplant Setting: Differential Diagnosis and Impact on Health and Health Care

Acute kidney injury (AKI) is common in kidney transplant recipients. In addition to the usual causes of AKI in native kidneys, certain features and risk factors are unique to kidney allografts. In this article, we will present an overview of the common transplant-specific AKI etiologies that include increased susceptibility to hemodynamic-mediated AKI, acute rejection, medication-induced AKI, recurrence of native kidney disease, infections, urinary tract obstruction, vascular thrombosis and post-transplant lymphoproliferative disorder. AKI is independently associated with allograft loss and patient mortality. It is, therefore, prudent for transplant centers to address it as a major quality measure.

18F-FDG PET/CT for the Diagnosis of Malignant and Infectious Complications After Solid Organ Transplantation

PURPOSE

Infection and malignancy represent two common complications after solid organ transplantation, which are often characterized by poorly specific clinical symptomatology. Herein, we have evaluated the role of ¹⁸F-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography/computed tomography (PET/CT) in this clinical setting.

METHODS

Fifty-eight consecutive patients who underwent FDG PET/CT after kidney, lung or heart transplantation were included in this retrospective analysis. Twelve patients underwent FDG PET/CT to strengthen or confirm a diagnostic suspicion of malignancies. The remaining 46 patients presented with unexplained inflammatory syndrome, fever of unknown origin (FUO), CMV or EBV seroconversion during post-transplant follow-up without conclusive conventional imaging. FDG PET/CT results were compared to histology or to the finding obtained during a clinical/imaging follow-up period of at least 6 months after PET/CT study.

RESULTS

Positive FDG PET/CT results were obtained in 18 (31 %) patients. In the remaining 40 (69 %) cases, FDG PET/CT was negative, showing exclusively a physiological radiotracer distribution. On the basis of a patient-based analysis, FDG PET/CT's sensitivity, specificity, PPV and NPV were respectively 78 %, 90 %, 78 % and 90 %, with a global accuracy of 86 %. FDG PET/CT was true positive in 14 patients with bacterial pneumonias (n = 4), pulmonary fungal infection (n = 1), histoplasmosis (n = 1), cutaneous abscess (n = 1), inflammatory disorder (sacroiliitis) (n = 1), lymphoma (n = 3) and NSCLC (n = 3). On the other hand, FDG PET/CT failed to detect lung bronchoalveolar adenocarcinoma, septicemia, endocarditis and graft-versus-host disease (GVHD), respectively, in four patients. FDG PET/CT contributed to adjusting the patient therapeutic strategy in 40 % of cases.

CONCLUSIONS

FDG PET/CT emerges as a valuable technique to manage complications in the post-transplantation period. FDG PET/CT should be considered in patients with severe unexplained inflammatory syndrome or FUO and inconclusive conventional imaging or to discriminate active from silent lesions previously detected by conventional imaging particularly when malignancy is suspected.

Matched-pair analysis: identification of factors with independent influence on the development of PTLD after kidney or liver transplantation

BACKGROUND

Post-transplant lymphoproliferative disorder (PTLD) adversely affects patients' long-term outcome.

METHODS

The paired t test and McNemar's test were applied in a retrospective 1:1 matched-pair analysis including 36 patients with PTLD and 36 patients without PTLD after kidney or liver transplantation. Matching criteria were age, gender, indication, type of transplantation, and duration of follow-up. All investigated PTLD specimen were histologically positive for EBV. Risk-adjusted multivariable regression analysis was used to identify independence of risk factors for PTLD detected in matched-pair analysis. The resultant prognostic model was assessed with ROC-curve analysis.

RESULTS

Patients suffering with PTLD had shorter mean survival (p = 0.004), more episodes of CMV infections or reactivations (p = 0.042), and fewer recipient HLA A2 haplotypes (p = 0.007), a tacrolimus-based immunosuppressive regimen (p = 0.052) and higher dosages of tacrolimus at hospital discharge (Tac dosage) (p = 0.052). Significant independent risk factors for PTLD were recipient HLA A2 (OR = 0.07, 95 % CI = 0.01-0.55, p = 0.011), higher Tac dosages (OR = 1.29, 95 % CI = 1.01-1.64, p = 0.040), and higher numbers of graft rejection episodes (OR = 0.38, 95 % CI = 0.17-0.87, p = 0.023). The following prognostic model for the prediction of PTLD demonstrated good model fit and a large area under the ROC curve (0.823): PTLD probability in % = Exp(y)/(1 + Exp(y)) with y = 0.671 - 1.096 × HLA A2-positive recipient + 0.151 × Tac dosage - 0.805 × number of graft rejection episodes.

CONCLUSIONS

This study suggests prognostic relevance for recipient HLA A2, CMV, and EBV infections or reactivations and strong initial tacrolimus-based immunosuppression. Patients with risk factors may benefit from intensified screening for PTLD.

Post-transplant lymphoproliferative disorder in paediatric patients: the Irish perspective-a single centre experience

BACKGROUND

Post-transplant lymphoproliferative disease (PTLD) is a serious complication of both solid organ and haematopoietic stem cell transplantation in children. Its incidence has increased over the last decade as a result of more potent immunosuppressive regimens. Many treatments have been explored however optimal therapy remains controversial.

AIMS

We report on the diagnosis, treatment and outcome of ten patients who were diagnosed with PTLD in Our Lady's Hospital for Sick Children in Dublin between 2004 and 2015 inclusive.

METHODS

Data were collected by retrospective review of patient medical records.

RESULTS

9 out of ten of our patients are alive and disease free following treatment for PTLD with rituximab alone or in combination with chemotherapy.

CONCLUSION

The outcome of paediatric patients treated for PTLD at our institution is at least comparable to published international series and supports the use of rituximab ± low dose chemotherapy in the treatment of this malignancy.

Lowered Immune Cell Function in Liver Recipients Recovered From Posttransplant Lymphoproliferative Disease Who Developed Graft Tolerance

Tolerance after treatment and recovery from posttransplant lymphoproliferative disease (PTLD) have been described but little is known about the immunology. The objective of this study is to evaluate the immunity of pediatric recipients who recovered from PTLD.

Post-transplant lymphoproliferative disorders

Post-transplant lymphoproliferative disorders (PTLDs) are a group of conditions that involve uncontrolled proliferation of lymphoid cells as a consequence of extrinsic immunosuppression after organ or haematopoietic stem cell transplant. PTLDs show some similarities to classic lymphomas in the non-immunosuppressed general population. The oncogenic Epstein-Barr virus (EBV) is a key pathogenic driver in many early-onset cases, through multiple mechanisms. The incidence of PTLD varies with the type of transplant; a clear distinction should therefore be made between the conditions after solid organ transplant and after haematopoietic stem cell transplant. Recipient EBV seronegativity and the intensity of immunosuppression are among key risk factors. Symptoms and signs depend on the localization of the lymphoid masses. Diagnosis requires histopathology, although imaging techniques can provide additional supportive evidence. Pre-emptive intervention based on monitoring EBV levels in blood has emerged as the preferred strategy for PTLD prevention. Treatment of established disease includes reduction of immunosuppression and/or administration of rituximab (a B cell-specific antibody against CD20), chemotherapy and EBV-specific cytotoxic T cells. Despite these strategies, the mortality and morbidity remains considerable. Patient outcome is influenced by the severity of presentation, treatment-related complications and risk of allograft loss. New innovative treatment options hold promise for changing the outlook in the future.

Practical Applications in Immunohistochemistry: Evaluation of Rejection and Infection in Organ Transplantation

CONTEXT

-Immunohistochemical analysis of tissue biopsy specimens is a crucial tool in diagnosis of both rejection and infection in patients with solid organ transplants. In the past 15 years, the concept of antibody-mediated rejection has been refined, and diagnostic criteria have been codified in renal, heart, pancreas, and lung allografts (with studies ongoing in liver, small intestine, and composite grafts), all of which include immunoanalysis for the complement split product C4d.

OBJECTIVES

-To review the general concepts of C4d biology and immunoanalysis, followed by organ-allograft-specific data, and interpretative nuances for kidney, pancreas, and heart, with discussion of early literature for lung and liver biopsies. Additionally, practical applications and limitations of immunostains for infectious organisms (Polyomavirus, Adenoviridae [adenovirus], and the herpes virus family, including Herpes simplex virus, Cytomegalovirus, Human herpes virus 8, and Epstein-Barr virus) are reviewed in the context of transplant recipients.

DATA SOURCES

-Our experience and published primary and review literature.

CONCLUSIONS

-Immunohistochemistry continues to have an important role in transplant pathology, most notably C4d staining in assessment of antibody-mediated rejection and assessment of viral pathogens in tissue. In all facets of transplant pathology, correlation of morphology with special studies and clinical data is critical, as is close communication with the transplant team.

How I treat posttransplant lymphoproliferative disorders

Posttransplant lymphoproliferative disorder (PTLD) is a potentially fatal disorder arising after solid organ transplant (SOT) or hematopoietic stem cell transplant (HSCT). Iatrogenically impaired immune surveillance and Epstein-Barr virus (EBV) primary infection/reactivation are key factors in the pathogenesis. However, current knowledge on all aspects of PTLD is limited due to its rarity, morphologic heterogeneity, and the lack of prospective trials. Furthermore, the broad spectrum of underlying immune disorders and the type of graft represent important confounding factors. Despite these limitations, several reviews have been written aimed at offering a guide for pathologists and clinicians in diagnosing and treating PTLD. Rather than providing another classical review on PTLD, this "How I Treat" article, based on 2 case reports, focuses on specific challenges, different perspectives, and novel insights regarding the pathogenesis, diagnosis, and treatment of PTLD. These challenges include the wide variety of PTLD presentation (making treatment optimization difficult), the impact of EBV on pathogenesis and clinical behavior, and the controversial treatment of Burkitt lymphoma (BL)-PTLD.

Posttransplantation lymphoproliferative disease: proposed imaging classification

Posttransplantation lymphoproliferative disease (PTLD) is the second most common tumor in adult transplant recipients. Most cases of PTLD are attributed to Epstein-Barr virus. Decreased levels of immunosurveillance against this tumor virus as a result of immunosuppressive regimens are thought to account for most cases of PTLD. Histologically, PTLD ranges from relatively benign lymphoid hyperplasia to poorly differentiated lymphoma, and tissue sampling is required to establish the subtype. The frequency of PTLD varies depending on the type of allograft and immunosuppressive regimen. PTLD has a bimodal manifestation, with most cases occurring within the first year after transplantation and a second peak occurring 4-5 years after transplantation. Patients are often asymptomatic or present with nonspecific symptoms, and a mass visible at imaging may be the first clue to the diagnosis. Imaging plays an important role in identifying the presence of disease, guiding tissue sampling, and evaluating response to treatment. The appearance of PTLD at imaging can vary. It may be nodal or extranodal. Extranodal disease may involve the gastrointestinal tract, solid organs, or central nervous system. Solid organ lesions may be solitary or multiple, infiltrate beyond the organ margins, and obstruct organ outflow. Suggestive imaging findings should prompt tissue sampling, because knowledge of the PTLD subtype is imperative for appropriate treatment. Treatment options include reducing immunosuppression, chemotherapy, radiation therapy, and surgical resection of isolated lesions.

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.

The Basics of Renal Allograft Pathology

Renal allograft biopsy provides critical information in the management of renal transplant patients, and must be analyzed in close collaboration with the clinical team. The histologic correlates of acute T-cell mediated rejection are interstitial inflammation, tubulitis, and endothelialitis; polyomavirus nephropathy is a potential mimic. Evidence of antibody-mediated rejection includes C4d deposition; morphologic acute tissue injury; and donor specific antibodies. Acute tubular injury/necrosis is a reversible cause of impaired graft function, especially in the immediate post-transplant period. Drug toxicity, recurrent disease, chronic injury, and other entities affecting both native and transplant kidneys must also be evaluated.

Endometrial polyps in female allograft recipients with abnormal bleedings

Introduction

Endometrial polyps are a common focal endometrial pathology, with abnormal uterine bleeding (AUB) as a predominant symptom. Although the great majority of cases are benign, premalignancy or malignancy may develop within the polyp. The need for chronic immunosuppressive therapy in solid organ transplanted patients is associated with a significantly increased risk of malignant lesions.

Aim of the study

Aim of the study was to evaluate the risk of endometrial polyps in solid organ transplanted women with abnormal uterine bleeding.

Material and methods

The retrospective analysis of 125 cases of AUB in allograft recipients and 200 consecutive cases of AUB in patients from the general population was performed. Pathological findings from dilatation and curettage were analyzed and compared between the groups.

Results

Endometrial polyps were the only pathological findings in 12% and 21.5% of cases from the study and the control groups, respectively. In each of the groups, one case of endometrial cancer coexisted with an endometrial polyp. If cases of endometrial polyps coexisting with endometrial hyperplasia were taken into account, the rate of endometrial polyps was similar to that observed in the general population (20% vs. 21.5%, respectively).

Conclusions

Chronic immunosuppression, associated with an increased risk of malignancy, does not increase the risk of endometrial polyps among female graft recipients.

Post-transplant lymphoproliferative disease (PTLD): risk factors, diagnosis, and current treatment strategies

Post-transplant lymphoproliferative diseases (PTLD) are heterogeneous lymphoid disorders ranging from indolent polyclonal proliferations to aggressive lymphomas that complicate solid organ or hematopoietic transplantation. Risk factors for PTLD include viral infections, degree of immunosuppression, recipient age and race, allograft type, and host genetic variations. Clinically, extra-nodal disease is common including 10-15 % presenting with central nervous system (CNS) disease. Most PTLD cases are B cell (5-10 % T/NK cell or Hodgkin lymphoma), while over one-third are EBV-negative. World Health Organization (WHO) diagnostic categories are: early lesions, polymorphic, and monomorphic PTLD; although in practice, a clear separation is not always possible. Therapeutically, reduction in immunosuppression remains a mainstay, and recent data has documented the importance of rituximab +/- combination chemotherapy. Therapy for primary CNS PTLD should be managed according to immunocompetent CNS paradigms. Finally, novel treatment strategies for PTLD have emerged, including adoptive immunotherapy and rational targeted therapeutics (e.g., anti-CD30 based therapy and downstream signaling pathways of latent membrane protein-2A).

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.

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.

Risk of lymphoma subtypes after solid organ transplantation in the United States

BACKGROUND

Solid organ transplant recipients have high risk of lymphomas, including non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL). A gap in our understanding of post-transplant lymphomas involves the spectrum and associated risks of their many histologic subtypes.

METHODS

We linked nationwide data on solid organ transplants from the US Scientific Registry of Transplant Recipients (1987-2008) to 14 state and regional cancer registries, yielding 791 281 person-years of follow-up for 19 distinct NHL subtypes and HL. We calculated standardised incidence ratios (SIRs) and used Poisson regression to compare SIRs by recipient age, transplanted organ, and time since transplantation.

RESULTS

The risk varied widely across subtypes, with strong elevations (SIRs 10-100) for hepatosplenic T-cell lymphoma, Burkitt's lymphoma, NK/T-cell lymphoma, diffuse large B-cell lymphoma, and anaplastic large-cell lymphoma (both systemic and primary cutaneous forms). Moderate elevations (SIRs 2-4) were observed for HL and lymphoplasmacytic, peripheral T-cell, and marginal zone lymphomas, but SIRs for indolent lymphoma subtypes were not elevated. Generally, SIRs were highest for younger recipients (<20 years) and those receiving organs other than kidneys.

CONCLUSION

Transplant recipients experience markedly elevated risk of a distinct spectrum of lymphoma subtypes. These findings support the aetiologic relevance of immunosuppression for certain subtypes and underscore the importance of detailed haematopathologic workup for transplant recipients with suspected lymphoma.

Decreasing incidence of symptomatic Epstein-Barr virus disease and posttransplant lymphoproliferative disorder in pediatric liver transplant recipients: report of the studies of pediatric liver transplantation experience

Posttransplant lymphoproliferative disorder (PTLD) causes significant morbidity and mortality in pediatric recipients of liver transplantation (LT).

OBJECTIVE

Describe the incidence of PTLD and symptomatic Epstein-Barr virus (SEBV) disease in a large multicenter cohort of children who underwent LT with a focus on the risk factors and changes in incidence over time. SEBV and PTLD were prospectively determined in 2283 subjects who had undergone LT for the first time with at least 1 year of follow-up in the Studies of Pediatric Liver Transplantation database. SEBV was defined with specific criteria, and PTLD required tissue confirmation. The incidence of SEBV and PTLD was determined with a Kaplan-Meier analysis. Univariate and multivariate modeling of risk factors was performed with standard methods. SEBV occurred in 199 patients; 174 (87.4%) were EBV-negative at LT. Seventy-five patients developed PTLD, and 64 (85.3%) of these patients were EBV-negative at LT. Among the 2048 patients with at least 2 years of follow-up, 8.3% developed SEBV by the second year after LT, and 2.8% developed PTLD. There were lower rates of SEBV (5.9% versus 11.3%, P < 0.001) and PTLD (1.7% versus 4.2%, P = 0.001) in 2002-2007 versus 1995-2001. In 2002-2007, tacrolimus and cyclosporine trough blood levels in the first year after LT were significantly lower, and fewer children were receiving steroids. Biliary atresia, and recipient EBV status were correlated. In a multivariate analysis, era of LT, recipient EBV status, and frequent rejection episodes were associated with SEBV and PTLD. The incidence of SEBV and PTLD is decreasing in pediatric LT recipients concomitantly with a reduction in immunosuppression. Younger recipients and those with multiple rejections remain at higher risk for SEBV and PTLD.

Posttransplant Lymphoproliferative Disorder after Cardiac Transplantation in Children: Life Threatening Complications Associated with Chemotherapy Combined with Rituximab

Despite the excellent long-term survival currently achieved in pediatric heart transplant recipients, posttransplant lymphoproliferative disorders (PTLDs) are one of the most important causes of morbidity and mortality after heart transplantation (HTx), especially in children. Timely and accurate diagnosis based on histological examination of biopsy tissue is essential for early intervention for PTLD. Chemotherapy is indicated for patients with poor response to reduction of immunosuppressive medication and for highly aggressive monomorphic PTLD. The use of rituximab in combination with chemotherapy is effective to suppress B cell type PTLD (B-PTLD). However, PTLD relapses frequently and the outcome is still poor. Although everolimus (EVL) has been reported to inhibit growth of human Epstein-Barr-virus- (EBV-) transformed B lymphocytes in vitro and in vivo, EVL has several side effects, such as delayed wound healing and an increase in bacterial infection. During combined treatment of chemotherapy and rituximab, B-PTLDs are sometimes associated with life-threatening complications, such as intestinal perforation and cardiogenic shock due to cytokine release syndrome. In HTx children especially treated with EVL, stoma should be made to avoid reoperation or sepsis in case of intestinal perforation. In cases with cardiac graft dysfunction possibly due to cytokine release syndrome by chemotherapy with rituximab for PTLD, plasma exchange is effective to restore cardiac function and to rescue the patients.

Single-center analysis of biopsy-confirmed posttransplant lymphoproliferative disorder: incidence, clinicopathological characteristics and prognostic factors

Hematopoietic stem cell and solid organ transplant recipients diagnosed with biopsy-confirmed posttransplant lymphoproliferative disorder (PTLD) at our institution from 1989 to 2010 were identified. Patient-, transplant- and disease-related characteristics, prognostic factors and outcome were collected and analyzed. One hundred and forty biopsy-proven cases of PTLD were included. Overall incidence in the transplant population was 2.12%, with heart transplant recipients carrying the highest risk. Most PTLDs were monomorphic (82%), with diffuse large B-cell lymphoma being the most frequent subtype. The majority of cases (70.7%) occurred > 1 year posttransplant, and 66% were Epstein-Barr virus positive. Following initial therapy the overall response rate was 68.5%. Three-year relapse-free and overall survivals were 59% and 49%, respectively. At last follow-up, 44% of the patients were alive. Multivariable analysis identified several classical lymphoma-specific poor prognostic factors for the different outcome measures. The value of the International Prognostic Index was confirmed in our analysis.

Plasmablastic lymphoma following transplantation

Posttransplant lymphoproliferative disorder is a serious complication following solid organ as well as hematopoietic stem cell transplantation due to prolonged immunosuppressive therapy. Plasmablastic lymphoma, although classically associated with HIV infection, has since been described in transplant patients as a variant of posttransplant lymphoproliferative disorder with varying clinical presentations. Here we add two additional cases to the literature: one following lung transplantation and one following pancreatic transplantation. In addition, the demographic, therapeutic, and immunophenotypic characteristics from prior reported cases are summarized.

Immunosuppressive and immunomodulatory therapy-associated lymphoproliferative disorders

A variety of therapeutic agents may increase the risk of lymphoproliferative disorders/neoplasms. These include those agents used to treat other malignancies (i.e., cytotoxic chemotherapy) and those used to treat or prevent certain diseases (or graft rejection) that alter the immune system. This review is restricted to the secondary lymphoid disorders that are unrelated to primary DNA damage by cytotoxic chemotherapy, and thus will include discussions regarding post-transplant lymphoproliferative disorders and those lymphoproliferations associated with the therapy of autoimmune and other immune-mediated diseases. Three drugs, or classes of drugs, used in the treatment of autoimmune and other immune-mediated diseases are discussed in some detail. These include methotrexate, anti-metabolites (including thiopurines and mycophenolate mofetil), and immunomodulators. The appropriate recognition of these disorders is important in order to correctly classify and institute appropriate therapy, recognizing that reduced immunosuppression or withdrawal of therapy may be necessary, rather than treating as a malignant lymphoma.

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.

Molecular diagnosis and management of viral infections in hematopoietic stem cell transplant recipients

Viral infections after allogeneic hematopoietic stem cell transplantation (HSCT) are important complications associated with high morbidity and mortality. In this setting, reactivations of persisting latent viral pathogens from donor and/or recipient cells play a central role whereas the sterile environment of transplant units renders new infections less likely. The viruses currently regarded as most relevant in the HSCT setting include particularly the herpes virus family--specifically cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpesvirus 6 (HHV-6)--as well as human adenoviruses (AdVs) and the polyoma virus BK (BKV). Timely detection and monitoring of virus copy numbers are prerequisites for successful preemptive treatment approaches. Pre- and post-transplant surveillance by sensitive and quantitative molecular methods has therefore become an essential part of the diagnostic routine. In this review, we discuss diagnostic aspects and the clinical management of the most important viral infections in HSCT recipients, with a focus on pediatric patients.

Bone marrow findings of 23 Korean post-transplant lymphoproliferative disorder patients: a single-center experience

BACKGROUND

Work-up of post-transplant lymphoproliferative disorders (PTLDs) often involves bone marrow (BM) examinations. We evaluated 23 transplant patients with PTLDs to investigate incidence of BM involvement and associated morphologic changes as well as prognosis.

METHODS

We retrospectively assessed BM findings of 23 transplant patients with PTLDs who had undergone BM staging at Seoul Asan Medical Center from 1994 to 2010.

RESULTS

Four (17%) showed BM involvement of PTLDs, including two pathologically diagnosed with PTLD by liver and skin biopsy and two diagnosed by BM examination. PTLD subtypes in four patients were all monomorphic, with one each having plasma cell myeloma, diffuse large B cell lymphoma, monomorphic B cell lineage, and monomorphic T-cell lineage. Epstein-Barr virus (EBV) in situ hybridization showed 11 of 23 (47.8%) patients were EBV positive, including two patients with BM involvement, one each with plasma cell myeloma and monomorphic T-cell lineage. Epstein-Barr virus infection was observed in nine of 19 patients (39.1%) without BM involvement or morphologic abnormalities. Mortality rate was higher in patients with than without BM involvement (p = 0.050).

CONCLUSION

High incidence of BM involvement in patients with PTLD and high mortality rates of these patients suggest BM examination study may be important in diagnosis and staging work-up of PTLD.

Post transplant lymphoproliferative disorders: risk, classification, and therapeutic recommendations

OPINION STATEMENT

Post transplant lymphoproliferative disorder (PTLD) is a heterogeneous disease that may occur in recipients of solid organ transplants (SOT) and hematopoietic stem cell transplant. The risk of lymphoma is increased 20-120% compared with the general population with risk dependent in part on level of immune suppression. In addition, recent data have emerged, including HLA and cytokine gene polymorphisms, regarding genetic susceptibility to PTLD. Based on morphologic, immunophenotypic, and molecular criteria, PLTD are classified into 4 pathologic categories: early lesions, polymorphic, monomorphic, and classical Hodgkin lymphoma. Evaluation by expert hematopathology is critical in establishing the diagnosis. The aim of therapy for most patients is cure with the concurrent goal of preservation of allograft function. Given the pathologic and clinical heterogeneity of PTLD, treatment is often individualized. A mainstay of therapy remains reduction of immune suppression (RI) with the level of reduction being dependent on several factors (e.g., history of rejection, current dosing, and type of allograft). Outside of early lesions and/or low tumor burden, however, RI alone is associated with cure in a minority of subjects. We approach most newly-diagnosed polymorphic and monomorphic PTLDs similarly using frontline single-agent rituximab (4 weeks followed by abbreviated maintenance) in conjunction with RI. Frontline combination chemotherapy may be warranted for patients with high tumor burden in need of prompt response or following failure of RI and/or rituximab. Due to chemotherapy-related complications in PTLD, especially infectious, we advocate comprehensive supportive care measures. Surgery or radiation may be considered for select patients with early-stage disease. For PTLD subjects with primary CNS lymphoma, we utilize therapeutic paradigms similar to immunocompetent CNS lymphoma using high-dose methotrexate-based therapy with concurrent rituximab therapy and sequential high-dose cytarabine. Finally, novel therapeutic strategies, especially adoptive immunotherapy, should continued to be explored.

Primary central nervous system post-transplant lymphoproliferative disorders following allogeneic hematopoietic stem cell transplantation

Post-transplant lymphoproliferative disorder (PTLD) is a serious complication after allogeneic hematopoietic stem cell transplantation (HSCT). Extra nodal involvement is common in PTLD, but isolated involvement of the central nervous system (CNS) is extremely rare. Given the rarity of primary CNS-PTLD there is no consensus on optimal treatment. We report a patient who developed Epstein-Barr virus related primary CNS-PTLD following allogeneic HSCT who was treated with the monoclonal anti-CD20 antibody rituximab and reduction of immunosuppression. In addition, we review the literature and discuss treatment options for patients with primary CNS-PTLD following allogeneic HSCT.

Cutaneous lymphoproliferative disorder complicating infectious mononucleosis in an immunosuppressed patient

Infectious mononucleosis is the syndrome produced by primary infection with Epstein-Barr virus during adolescence or early adulthood. In immunosuppressed individuals, depressed T-cell function allows the Epstein-Barr virus-driven B-cell proliferation to continue unabated, potentially leading to a lymphoproliferative disorder. A 15-year-old girl with a history of ulcerative colitis treated with 6-mercaptopurine and mesalamine presented with the acute onset of a rapidly enlarging, ulcerative nodule on her left lower eyelid 4 weeks following recovery from infectious mononucleosis. The biopsy revealed an Epstein-Barr virus-positive lymphoproliferative disorder. Systemic disease was absent. Following discontinuation of 6-mercaptopurine, the patient was treated with two courses of intravenous cyclophosphamide. The lesion resolved completely and she remains disease free at 14 months following diagnosis. We report a solitary cutaneous lesion of an immunosuppression-related lymphoproliferative disorder (IR-LPD) occurring as a complication of infectious mononucleosis, and review the pathogenesis and reported cases of Epstein-Barr virus-related immunosuppression-related lymphoproliferative disorder arising in the setting of inflammatory bowel disease. It is important for dermatologists and dermatopathologists to be aware of the occurrence of IR-LPD in patients being treated for inflammatory conditions, including inflammatory bowel disease. Given the role of primary infection with Epstein-Barr virus in the development of IR-LPD, consideration may be given to assessing Epstein-Barr virus status prior to initiating immunosuppressive therapy in young patients.

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.