Post-transplant Lymphoproliferative Disorder Patients Research Articles

Infectious Complications and Mortality in Post-Transplant Lymphoproliferative Disorder Following Solid Organ Transplantation: Experiences of 10 Years in a Single Center

Introduction: An estimated 2 to 20% of patients with solid organ transplants (SOT) are later diagnosed with post-transplant lymphoproliferative disorder (PTLD). These patients receive immunosuppression therapy for SOT, however, there is a paucity of research examining the infection complications and morbidity in those diagnosed with PTLD. Our single center study examined infections following a PTLD diagnosis and the potential risk of morbidity. Methods: We reviewed the Cleveland Clinic electronic medical record (EMR) of SOT patients who were diagnosed with PTLD between 2010 and 2020. 98 patients met the inclusion criteria. These were further stratified by transplant type: 26 liver, 24 renal, 22 lung, 19 heart, and 2 combined heart and lung transplant patients. All data were analyzed using R software. Results: The mean onset of biopsy confirmed PTLD following transplant was 7.13 ± 7.28 years,. Abdominal pain was the most common presenting symptom prompting further work up, seen in 29% of patients. Patients were also diagnosed based on other chief complaints, including fatigue (n = 20), weight loss (n = 16), and fever (n = 14). Additionally, a smaller subset of patients were diagnosed incidentally on imaging. The most frequent primary site of PTLD was the lymphoid tissue / enlarged lymph nodes (34% of patients) and followed by gastrointestinal tract (29%). Elevated lactate dehydrogenase was present in 42% of patients, diagnostic criteria for acute kidney injury in 23%, and hyperuricemia was noted in 16%. Diffuse large B-lymphoma was the most common subtype diagnosed in 72 of 98 patients followed by EBV related. After diagnosis, 60% of PTLD patients presented to the hospital due to infections, with a mean of 49.9 ± 55.3 days following PTLD diagnosis. Of those patients, bacterial infections were the most common (49.3%), followed by viral infections (34.5%), fungal infections (14.9%), and parasitic infections (1.15%). The bacterial infections were predominantly encapsulated organisms including Pseudomonas aeruginosa (33%), Escherichia coli (19%), and Streptococcus pneumoniae (14%). Rituximab was used in 40% of patients following diagnosis while rituximab, cyclophosphamide, doxorubicin, and vincristine (R-CHOP) was used in 41% of patients. There was no significant difference in infection risk in the first 100-days, following initiation of rituximab infections were seen in 33%, while the infection risk with R-CHOP was 35% (p = 0.31). Moreover, the most common cause of death was infection seen in 39% of patients, while PTLD itself with progressive disease was the second most common cause of death in 27%. The 6-month mortality following PTLD was 16% with 56% of those deaths being attributed to infection. The one-year mortality rate following PTLD was 25% with 48% of those being attributed to infection. Conclusions: In patients with PTLD diagnosis, the most common cause of death was infection (39%), followed by complications related to PTLD such as progressive disease with multi-organ failure. High serious infection risk may be due to aberrant monoclonal B-cell proliferation which paradoxically leads to decreased cellular immunity. The increased risk of B-cell PTLD in patients with SOT is likely due to the chronic immunosuppression, where patients gain acquired somatic driver mutations leading to a malignant state yet with an increased infection risk. Additionally, there was no difference in infection at 100 days between rituximab chemotherapy compared to R-CHOP. This necessitates the question of initiating viral, bacterial and fungal infection prophylaxis, similar to that following splenectomy or post BMT, should be implemented in patients diagnosed with PTLD. Further larger prospective studies are needed to further analyze the potential need and benefit of prophylactic vaccinations at the time of diagnosis in the PTLD patient population.

Role of brentuximab vedotin plus sirolimus in the treatment of classical Hodgkin lymphoma type post-transplant lymphoproliferative disorder: a case-based review.

Post-transplant lymphoproliferative disorder (PTLD) is a common secondary malignancy after transplantation, which has been recognized as a life-threatening complication. Hodgkin lymphoma (HL)-type PTLD is the rarest of four subtypes of PTLD, which has no treatment guideline due to its rarity. HL-type PTLD includes classical HL-type PTLD (cHL-PTLD) and HL-like PTLD. In our study, we reported the case of successful treatment using brentuximab vedotin (BV) plus sirolimus for a patient with classical HL-type PTLD in detail. Lymph node biopsy showed a picture of classical HL with mixed cellularity subtype, and immunophenotyping suggested CD30 strong positivity. Due to his impaired physical condition, we decided against intensive chemotherapy and started BV treatment with immunosuppressive agents switched to sirolimus. The 66-year-old patient with cHL-PTLD had achieved a durable complete remission for over a 1-year follow-up period. Additionally, we analyzed the clinical profile and outcomes in PTLD patients who used BV monotherapy or combined therapy by literature review. In summary, this case-based review might provide clues that treatment of cHL-PTLD with new modalities such as BV monotherapy or combination therapy, together with improvements in the immunosuppressive regimens like sirolimus, might be a feasible and chemotherapy-free approach, but warrants further evaluation in a larger patient cohort.

Incidence and Features of Lymphoid Proliferation and Lymphomas after Solid Organ or Hematopoietic Stem Cell Transplantation in a National Database Cohort.

Post-transplantation lymphoproliferative disorders (PTLDs) after hematopoietic stem transplantation (HCT) or solid organ transplantation (SOT) result in poorer outcomes, including death. There are limited large cohort data on the incidence and natural course of PTLD in Asians. We investigated PTLD using Korean national health insurance claims data of 47,518 patients who underwent HCT or SOT in 2008-2020. Patient demographics, time and type of PTLD diagnosis, type of PTLD treatment, and death data were collected. We used Fine and Gray subdistribution hazard models to calculate the cumulative incidence and risk factors for PTLD. During median follow-up of 5.32 years, PTLD occurred in 294 of 36,945 SOT patients (0.79%) and 235 of 10,573 HCT patients (2.22%). Cumulative incidence of PTLD were 0.49% at 1 year, 1.02% at 5 years, and 1.50% at 10 years post-transplantation. Age < 20 years (subdistribution hazard ratio [SHR] of 1.67 in age 10-19, SHR 1.51 in age 0-9), HCT (SHR 3.02), heart transplantation (SHR 2.27), and liver transplantation (SHR 1.47) were significant risk factors for PTLD. The presence of PTLD was associated with an increased risk of death (hazard ratio of 2.84). Overall, 5-year survival of PTLD patients was 68.9% (95% confidence interval, 64.9 to 73.2). We observed a steady increase in PTLD over 10 years after HCT or SOT in this large cohort study. Pediatric age group, HCT, liver transplantation, and heart transplantation were suggested to be risk factors for PTLD, and PTLD was associated with a higher risk of death.

EBV-encoded miRNAs BHRF1-1 and BART2-5p aggravate post- transplant lymphoproliferative disorder via LZTS2-PI3K-AKT axis

Post-transplant lymphoproliferative disorder (PTLD) is one of the most serious complications after transplantation. Epstein-Barr virus (EBV) is a key pathogenic driver of PTLD. About 80% of PTLD patients are EBV positive. However, the accuracy of preventing and diagnosing EBV-PTLD by monitoring EBV DNA load is limited. Therefore, new diagnostic molecular markers are urgently needed. EBV-encoded miRNAs can regulate a variety of EBV-associated tumors and are expected to be potential diagnostic markers and therapeutic targets. We found BHRF1-1 and BART2-5p were significantly elevated in EBV-PTLD patients, functionally promoting proliferation and inhibiting apoptosis in EBV-PTLD. Mechanistically, we first found that LZTS2 acts as a tumor suppressor gene in EBV-PTLD, and BHRF1-1 and BART2-5p can simultaneously inhibit LZTS2 and activate PI3K-AKT pathway. This study shows that BHRF1-1 and BART2-5p can simultaneously inhibit the expression of tumor suppressor LZTS2, and activate the PI3K-AKT pathway, leading to the occurrence and development of EBV-PTLD.Therefore, BHRF1-1 and BART2-5p are expected to be potential diagnostic markers and therapeutic targets for EBV-PTLD patients.

Non-invasive monitoring associated with B lymphoma cells in post-transplant lymphoproliferative disorder (PTLD) patients: Systematic review.

One of the most severe side effects of solid-organ transplantation is posttransplant lymphoproliferative disease (PTLD). People with human immunodeficiency virus infection (HIV), an immunosuppressive disease comparable to HIV, have a higher chance of developing lymphoma when their peripheral blood contains elevated levels of the immunoglobulins kappa and lambda free light chains (FLCs). This systematic review's objective was to monitor associated B lymphoma cells in PTLD patients. In order to find relevant studies published between 1/1/2000 and 1/9/2022, two independent researchers conducted searches (MT, AJ). A literature search of English language publications was conducted using MEDLINE through PubMed, EMBASETM through Ovid, the Cochrane Library, and Trip. In addition to Magiran and SID, we searched KoreaMed and LILACS for literature published in other languages. sFLC or PTLD, transplant, or Electrophoresis are terms used in the search strategy. A total of 174 studies were selected. After analyzing their correspondence with the required criteria, a final review of five studies was conducted. The manuscript presents current findings on the potential benefits of the clinical applicability of sFLCs in PTLD. While the preliminary results appear promising, the only consistent result is that early-onset PTLD is predicted within the first two years after transplant, a biomarker that could be used to diagnose the condition. Therefore, PTLD has been predicted by using the sFLCs. There have been contradictory results to date. Future research could include assessing the quantity of sFLCs and their quality in transplant recipients. In addition to PTLD and complications after transplantation, sFLCs may provide insight into other diseases. To confirm the validity of sFLCs, more studies are needed.

Important Considerations in the Diagnosis and Management of Post-transplant Lymphoproliferative Disorder.

A relative lack of molecular and clinical studies compared to other lymphoid cancers has historically made it difficult to determine optimal management approaches in post-transplant lymphoproliferative disorder (PTLD). We sought to better define the "state of the science" in PTLD by examining recent advances in risk assessment, genomic profiling, and trials of PTLD-directed therapy. Several major clinical trials highlight risk-stratified sequential therapy incorporating rituximab with or without chemotherapy as a rational treatment strategy in patients with CD20+ PTLD who do not respond to reduction of immunosuppression alone. Epstein Barr virus (EBV)-targeted cytotoxic lymphocytes are a promising approach in patients with relapsed/refractory EBV+ PTLD, but dedicated clinical trials should determine how autologous chimeric antigen receptor T cell therapy (CAR-T) may be safely administered to PTLD patients. Sequencing studies underscore the important effect of EBV infection on PTLD pathogenesis, but comprehensive genomic and tumor microenvironment profiling are needed to identify biomarkers that predict response to treatment in this clinically heterogeneous disease.

EBV-positive PCNSL in older patients: incidence, characteristics, tumor pathology, and outcomes across a large multicenter cohort

The objective of this multicenter retrospective study was to examine the incidence, patient characteristics, pathology, and outcomes associated with Epstein-Barr virus (EBV)-related CNS lymphoma (CNSL) in older patients. Among 309 CNSL patients aged ≥60, 11.7% had EBV + tumors of which 72.2% were solid organ transplant (SOT)-related post-transplant lymphoproliferative disorders (PTLD). Younger age, SOT or autoimmune disease, and immunosuppressive treatment correlated highly with EBV-positivity. EBV + tumors were associated with absent C-MYC and BCL6 expression. EBV + PTLD was more likely to be associated with the absence of CD5 expression. EBV + non-PTLD had better median OS (not reached) compared to EBV + PTLD (10.8 months) and EBV-negative patients (43 months). Multivariable Cox regression analysis showed that age, performance status, and PTLD were negative predictors of OS. EBV status and immunosuppressive treatment were not correlated with OS. Our findings merit further investigation of EBV + PCNSL tumors and EBV-directed therapies.

Genomic Landscaping of Post-Transplant Lymphoproliferative Disorders Using Circulating Tumor DNA

Introduction: Identification of post-transplant lymphoproliferative disorder (PTLD) is a diagnostic challenge. The current diagnostic framework usually require analysis on tissue and imaging through PET/CT scans. Yet, these methods have diagnostic limitations. For instance due to missing information on tumor heterogeneity and relatively low sensitivity of PET/CT scans. Measuring cell free DNA (cfDNA) represents a novel, minimally-invasive method for tumor detection and genotyping. In this study we explored the feasibility of plasma cfDNA tumor genotyping with targeted deep sequencing to detect copy number variation (CNV), single nucleotide variants (SNVs) and Epstein Bar Virus (EBV) sequences, using a new in-house variant calling pipeline. Methods: In this multi-center observational cohort study of 18 patients diagnosed with monomorphic PTLD, we performed deep targeted NGS for SNV detection and low-coverage whole genome sequencing (lcWGS) for CNV detection. NGS was targeted on a panel of genes (n = 39) known to be recurrently mutated in B-cell lymphomas (244 kbp). All patients gave written informed consent. The R package CNAclinic was used to identify genome wide CNAs and fraction of the genome altered (FGA). The ichorCNA package was used to determine the ctDNA fraction in cfDNA samples. SNVs were called using a pipeline, combining 4 (cfDNA) SNV calling tools: Mutect2, LoFreq, VarDict & SiNVICT. Variants were filtered on presumed functional effect (Synonymous-, UTR-, Intron-, 2 kb upstream-, 2 kb downstream variants were removed). A "panel of normals” (variant blacklist) was generated from variants found in cfDNA from healthy controls, which was used to produce a variant blacklist to filter out technical artifacts and SNPs. Finally, variants with a variant allele frequency (VAF) < 1% and variants with an allele frequency (AF) of > 1% in 1000Genomes and/or gnomAD were filtered out. Results: The cohort included 18 PTLD patients. The majority of patients had stage IV disease (n=13, 76%). All of the PTLD cases were histologically proven, of diffuse large B cell lymphoma type and 10/18 patients (55%) were considered to have an EBV-negative tumor. EBV copy number in plasma was performed by qPCR in 12 patients and was considered to be elevated in four patients (>5000 copies/mL). The fraction of reads mapping to the EBV genome was compared between controls (n=8), EBV-negative PTLD (n=10) and EBV-positive PTLD (n=8). The median fraction of EBV reads for controls and EBV-negative PTLD were similar with a fraction of 1.5x10-4 (Q1-Q3: 1.3x10-4-1.6x10-4) and 1.8x10-4 (Q1-Q3: 1.4x10-4-3.9x10-4), respectively (p>0.05, Kruskal-Wallis). In EBV-positive tumors, the median fraction of EBV reads was 3-log higher, 5.3x10-1 (Q1-Q3: 7.3 x10-2-2) (p≤0.05, Kruskal-Wallis) CNVs were detected in cfDNA of 11/18 (61%) patients. Two of the patients in whom no CNVs were detected had initiated therapy at the time of plasma sampling. Median fraction of genome altered was higher in EBV-negative tumors (0.03, Q1-Q3: 2.5x10-4-0.12) than in EBV-positive tumors (5x10-4, Q1-Q3: 0-0.03), but this difference was not significant (p>0.05, Mann-Whitney U) (Figure 1). In the top 15 recurrently mutated genes (described below), across all 18 samples, 180 SNVs were found in total. The median amount of SNVs found in each sample was 11 (range 6-25). The most frequently mutated gene was CREPPB (12/18, 67%), in which the most prevalent mutation was p.K1497T (8/18, 44%). ARID1A was mutated in 10/18 cases (56%), followed by KMT2D (9/18, 50%). TET2, TP53, MEF2B & TNFAIP3 were all mutated in 7/18 cases (39%). SPEN & IRF2BP2 were mutated in 6/18 cases (33%). PIM1, NOTCH1, ATM, CARD11, DDX3X, IGLL5 were all mutated in 5/18 cases (28%) (Figure 2). Few of the mutations that are called in the top 15 recurrently mutated genes (8/180, 0.04%) lay close to 50% VAF, which might imply that these are SNPs not filtered out by the pipeline. Our SNV findings are comparable with previous literature, in which KMT2D, TET2 & TP53 are also amongst top-mutated genes (Menter et al., 2017), highlighting disruption of epigenetic regulation, NFkB pathway, and DNA damage response as drivers of PTLD. Conclusion: lcWGS in combination deep targeted sequencing allows for detection of CNV an SNV in diagnostic samples of patients with monomorphic PTLD. These data can potentially be used at screening, diagnosis and response monitoring, which is part of the ongoing prospective study NTR 7402. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Methylome Analysis of Epstein-Barr Virus with Nanopore Sequencing Reveals Viral State Dynamics

Epstein Barr Virus (EBV) is a gammaherpesvirus responsible for a broad spectrum of human diseases, including hematologic malignancies and autoimmune disorders. EBV maintains lifelong infection by entering an endosomal state of latency inside its host cell. In response to external stimuli EBV undergoes lytic activation, resulting in vast gene expression changes, DNA replication, and eventually release of infectious viral particles. DNA methylation of the EBV genome is essential to regulating its life cycle. Both lytic and latent life stages are key determinants of EBV-driven disease, but current clinical assays for EBV are limited to detecting the presence of EBV and do not provide important information on EBV lytic state. Thus, making clinical decisions based on EBV detection alone has remained challenging. To address these limitations, we have developed an EBV analysis pipeline utilizing nanopore sequencing from amplification-free, native DNA that directly interrogates CpG dinucleotide DNA methylation on the EBV genome. Our workflow generates highly accurate EBV methylation calls for the majority of CpGs across the EBV genome. We also deployed a quantitative mass-spectrometry-based methylation assay (EpiTYPER) to validate our data and provide broader analysis of a representative subset of methylation sites (n=123 methylation sites from n=25 EBV loci). To initially investigate the relationship between locus-specific EBV DNA methylation and EBV gene expression, we compared DNA methylation and RNA sequencing profiles in EBV-positive cell lines (n=7). We correlated global EBV DNA methylation levels and the overall patterns of latent versus lytic EBV gene expression. We found that average methylation levels are related to the ratio of latent versus lytic gene expression, establishing nanopore-derived DNA methylation as a method to quantify latent and lytic states in a given sample. We next shifted our approach to bin nanopore reads based on the average methylation of all CpGs per read, hypothesizing that latent/lytic viral states derive from distinct subpopulations of EBV endosomes that contain methylated versus unmethylated DNA. We uncovered widespread co-occurrence of high and low methylated viral DNA in cell lines, indicating that EBV methylation states exist in defined subfractions with either present or absent DNA methylation. In cell models of latent EBV infection (Akata, Kem, MEC1, Mutu, Rael) this approach showed that methylation states dynamically responded to lytic induction and selective pressure via antiviral treatment with ganciclovir. Of note, we observed a shift in methylation without the appearance of partially methylated DNA, indicating that EBV lytic activation/replication is associated with the appearance of unmethylated EBV DNA, and not gradual demethylation of endosomes in the latent viral state. Finally, we aimed to obtain measurements of overall EBV status in patients, using nanopore sequencing of cell-free DNA (cfDNA) obtained from patient plasma. We analyzed patients diagnosed with different EBV-positive diseases from The Ohio State University Medical Center, including n=3 patients with lymphomas (Burkitt, plasmablastic and diffuse large B cell lymphoma) and n=2 patients with post-transplant lymphoproliferative disorder (PTLD). The patient samples with lymphoma displayed a near uniformly high methylation profile, with little evidence of unmethylated DNA/lytic replication. One of the PTLD patients analyzed showed a distinct bi-modal distribution of per read EBV methylation values, indicating the presence of lytic replication in a significant proportion of cells. In conclusion, nanopore sequencing analysis of methylated versus unmethylated EBV DNA subfractions is a quantitative method for determining viral states. In patient samples, nanopore sequencing revealed methylation heterogeneity in cfDNA and may be a useful advancement compared to standard clinical EBV detection. Quantifying the relative ratio of latent versus lytic virus in a liquid biopsy sample could be used to guide therapy selection for patients displaying EBV-positivity. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Management of Resistant Post-transplant Lymphoproliferative Disorder: CAR-T Is a New Option.

This is a review of the therapeutic options for resistant/refractory post-transplant lymphoproliferative disorder (PTLD) in relation to Chimeric antigen receptor-T cell (CAR-T) therapy. Out of a number of possible future strategies for the treatment of PTLD, the following methods were implemented in real-world practice: anti-PD1 therapy with checkpoint inhibitor nivolumab, new anti-CD20 ofatumumab, brentuximab vedotin, and zanubrutinib. However, for all these innovative methods, only individual cases of successful treatment of rituximab-resistant Epstein-Barr Virus (EBV)-PTLD patients have been reported so far. CAR-T is an innovative method of treatment, based on genetic modification of receptors of T autologous lymphocytes, creating the "living drug". This therapy can be potent against resistant PTLD, which is a lymphoproliferation of B-lymphocytes. The published real-world data of 17 patients treated with CAR-T for PTLD indicate a success rate of 76.5%. There is development of innovative methods of treatment of resistant/refractory PTLD, with high rate of resolution after CAR-T therapy.

Host microRNAs are decreased in pediatric solid-organ transplant recipients during EBV+ Post-transplant Lymphoproliferative Disorder.

Post-transplant lymphoproliferative disorder (PTLD) is a serious complication of solid organ transplantation. Predisposing factors include primary Epstein-Barr virus (EBV) infection, reactivation of EBV in recipient B cells, and decreased T cell immunity due to immunosuppression. In our previous studies EBV infection was demonstrated to markedly alter the expression of host B cell microRNA (miR). Specifically, miR-194 expression was uniquely suppressed in EBV+ B cell lines from PTLD patients and the 3’untranslated region of IL-10 was determined to be targeted by miR-194. Although EBV has been shown to regulate host miR expression in B cell lymphoma cell lines, the expression of miRs in the circulation of patients with EBV-associated PTLD has not been studied. The objective of this study was to determine if changes in miR expression are associated with EBV+ PTLD. In this study, we have shown that miR-194 is significantly decreased in EBV+PTLD tumors and that additional miRs, including miRs-17, 19 and 106a are also reduced in EBV+PTLD as compared to EBV-PTLD. We quantitated the levels of miRs-17, 19, 106a, 155, and 194 in the plasma and extracellular vesicles (EV; 50-70 nm as determined by nanoparticle tracking analysis) from pediatric recipients of solid organ transplants with EBV+ PTLD+ that were matched 1:2 with EBV+ PTLD- pediatric transplant recipients as part of the NIH-sponsored Clinical Trials in Organ Transplantation in Children, (CTOTC-06) study. Levels of miRs-17, 19, 106a, and 194 were reduced in the plasma and extracellular vesicles (EV) of EBV+ PTLD+ group compared to matched controls, with miRs-17 (p = 0.034; plasma), miRs-19 (p = 0.029; EV) and miR-106a (p = 0.007; plasma and EV) being significantly reduced. Similar levels of miR-155 were detected in the plasma and EV of all pediatric SOT recipients. Importantly, ~90% of the cell-free miR were contained within the EV supporting that EBV+ PTLD tumor miR are detected in the circulation and suggesting that EVs, containing miRs, may have the potential to target and regulate cells of the immune system. Further development of diagnostic, mechanistic and potential therapeutic uses of the miRs in PTLD is warranted.

ABCL-542 Prevalence and Characterization of EBV-Negative Post-Transplant Lymphoproliferative Disorder

A common and potentially fatal post-solid organ transplant (SOT) complication is post-transplant lymphoproliferative disorder (PTLD). While the association of Epstein-Barr virus (EBV) with the development of PTLD is well recognized, little is known about the etiology of EBV-negative PTLD. To characterize the differences between EBV-positive and EBV-negative PTLD to better understand the pathogenesis of EBV-negative PTLD. This was a retrospective study that reviewed patients who developed PTLD after SOT. Data was collected on PTLD patients (>18 years) from 2011 to 2021. Data included demographics, SOT type, time from SOT to PTLD development, tumor EBV status, PTLD site, histopathological morphology, tumor markers, and overall survival. EBV tumor status was compared using χ2, Fisher's Exact, and Wilcoxon Rank Sum tests. A single, large academic center. A total of 99 patients met the inclusion criteria. Of those, 45.5% were EBV-positive and 54.5% were EBV-negative. Tumor EBV status did not differ by race, but males were more likely to be EBV-negative (63% v. 44.4% of females, p=0.065). EBV tumor status did not differ by SOT type. The interval between SOT and PTLD diagnosis was longer in EBV-negative patients (8.68 years) than EBV-positive patients (4.93 years) (p=0.001). There was a significant difference in EBV-negative PTLD site (p=0.046) and PTLD subtypes (p=0.002). Site of EBV-negative PTLD consisted of gastrointestinal (38.9%), head/neck (11.1%), liver/spleen (11.1%), CNS (3.7%), other lymph (24%), and other non-lymph (11.1%). Monomorphic (65.5%) and T-cell (90%) subtypes were more common in EBV-negative patients, compared to the polymorphic (15.4%) and plasmablastic/plasmacytic (27.3%) subtypes. Expression of CD20 did not differ by tumor EBV status. Those who were CD30-negative were more likely to be EBV-negative (90% v. 25%, p=<0.001). Those who were CD138-negative were more likely to be EBV-negative (75% v. 26.7%, p=0.012). There was no difference in overall survival by tumor EBV status. This single institution retrospective review shows that there are distinct differences between EBV-negative and EBV-positive PTLD. EBV-negative PTLD has a longer interval from SOT to PTLD development, is more likely to occur in the gastrointestinal tract, and is more likely to have a monomorphic morphology.

Tumor Infiltrating Lymphocytes Predict Survival in Solid Organ Transplant Recipients With Monomorphic Post-transplant Lymphoproliferative Disorders.

The tumor microenvironment (TME) in post-transplant lymphoproliferative disorders (PTLDs) remains unexplored. Tumor infiltrating lymphocytes (TILs) are prognostic in other lymphomas. We assessed the prognostic impact of TILs in monomorphic B-cell PTLD. TIL density (CD3+ cells/mm2) was determined by CD3 immunohistochemistry in archived diagnostic biopsies from patients diagnosed with monomorphic B-cell PTLD. Amongst monomorphic PTLDs (N=107), low TIL-count was associated with inferior 2-year progression-free survival (PFS) (41% versus 86%, P=.003) and 2-year overall survival (OS) (52% versus 93%, P=.003) by Kaplan-Meier analysis. Low TIL-count was significant on Cox univariate regression for inferior PFS (HR 4.5, 95% CI 2.0-9.9, P < .001) and OS (HR 4.6, 95% CI 1.8-11.8, P < .001). Multivariate analysis with clinical variables (age ≥60 years, high LDH, stage III/IV, CNS involvement) and TIL-count showed significance for PFS (HR 3.3, 95% CI 1.3-8.3, P=.010) and a non-significant trend for OS (HR 2.6, 95% CI 0.9-7.3, P=.064). A composite score including TILs and clinical variables (age ≥60 years, high LDH, stage III/IV, CNS involvement) effectively stratified monomorphic PTLD patients by PFS and OS (2-year OS: low-risk 93%, intermediate-risk 61%, high-risk 23%, P < .001). The TME and TILs are prognostically relevant in monomorphic PTLD. Prognostic models including measures of the TME may improve risk stratification for patients with monomorphic PTLDs.

Histopathological and Clinical Features of Methotrexate-Associated Lymphoproliferative Disorders and Post-Transplant Lymphoproliferative Disorders

Objective: To study histopathological and clinical features of methotrexate-associated lymphoproliferative disorders (MTX-LPD) and post-transplant lymphoproliferative disorders (PTLD).Material and Methods: A retrospective study on 30 cases of MTX-LPD and 2 cases of PTLD from 2006 to 2021.Results: By histopathology, the MTX-LPD group had 21 cases of lymphoma (MTX-Lymphoma) and 9 cases of reactive changes (MTX-Reactive). The PTLD group included diffuse large B-cell lymphoma and polymorphic PTLD (1 case each). The distinctive findings in MTX-Lymphoma and PTLD were association with Epstein-Barr virus (EBV) (8/12 cases, 66.7%) and CD30 positivity (13/18 cases, 72.2%). The MTX-LPD group had median MTX dosage of 10 mg/week, median MTX cumulative dosage of 2,613.75 mg, and median duration of MTX usage of 2,186 days. The 14 MTX-LPD and PTLD patients has median duration to response after the varied interventions of 47 days and the time to the first complete remission (CR) of 126 days. The MTX-Reactive patients had a significantly higher absolute lymphocyte count, younger median age, fewer B symptoms, higher rate of single site involvement, less extranodal involvement, shorter duration to response, less time to enter CR, and higher CR rate than the MTXLymphoma patients (p &lt; 0.05).Conclusion: Histopathology in MTX-LPD and PTLD patients can vary from reactive changes to lymphoma. EBV study and CD30 immunostaining help identify MTX-LPD and PTLD. History of MTX usage and other causes of immunodeficiency should be considered before diagnosing lymphoma. MTX discontinuation or reduction of immunosuppressant dosage are recommended before administrating combined chemotherapeutic agents in unresponsive cases.

Clinical Post-Transplant Lymphoproliferative Disorders

Post-transplant lymphoproliferative disorders (PTLDs) are characterized by hyperproliferation of B cells due to solid organ or allogeneic hematopoietic stem cell transplant. Based on histological findings, it is divided into 4 categories. Most PTLD patients are Epstein-Barr virus (EBV) positive. Additionally, aggressive immunosuppressive therapies can also lead to PTLD. Reducing immunosuppressive regimes, antivirals, monoclonal antibodies, chemotherapy, and radiotherapy are available therapeutic options, depending on the nature and phase of the disease. This review briefly highlights pathogenesis, risk factors, prevention, and therapeutic strategies regarding PTLDs.

Outcomes and prognostic assessment of post-transplant lymphoproliferative disorder.

e19548 Background: Post-transplant lymphoproliferative disorder (PTLD) is the most common malignancy after solid organ transplantation (SOT) in adults, apart from skin cancer. It is a serious and potentially fatal complication of chronic immunosuppression in SOT recipients. Methods: Institutional electronic health record (EHR), Epic was queried for PTLD patients evaluated at the University of Cincinnati Cancer Center 1991 - 2020. Relationships between clinical characteristics and time from diagnosis to death were assessed using t-test and ANOVA, with SAS 9.4. Overall survival (OS) was evaluated by Kaplan Meier estimates, from the date of PTLD diagnosis to death or last follow-up. Results: Sixty patients were identified with PTLD in the study period. A higher proportion of males (65%) and Caucasians (92%) was noted. The most common type of transplants were kidney (40%) and liver (32%). The median time from transplant to PTLD was 7.3 y and the median age at diagnosis was 54.5 y. The majority had monomorphic PTLD (60%) and presented as Stage IV (25%) or with end-organ dysfunction (67%). Most had extranodal involvement (67%), with GI (23%) being the most frequently involved site. EBV was positive in 32%. Immunosuppression was changed in 75% of the patients and most received rituximab-chemotherapy (55%), with two-thirds achieving a response. The 2-year OS was 55%. Gender (males 44%, females 14%; p = 0.0216), transplant type (lung 67%, liver 53%, kidney 21%, kidney-pancreas 0%; p = 0.0183) and treatment response (CR 20%, PR 29%, no response 100%; p = 0.0003) were significantly associated with mortality. Median time from PTLD diagnosis to death was 5.2 mo, being significantly shorter in liver transplant recipients (p &lt; 0.0001), those managed by observation only (p &lt; 0.0001) or with end-organ dysfunction at diagnosis (0.0072). A similar trend was noted in males, non-Caucasians, HLA-mismatch, and polymorphic PTLD, but this was statistically nonsignificant. Conclusions: This investigation highlights the prognostic risk factors of PTLD, that could be helpful in the management of the patients and guiding future research.[Table: see text]

Nondestructive versus advanced post-transplant lymphoproliferative disorder in a single-center pediatric kidney transplant population.

Pediatric kidney transplant recipients are at risk for the development of post-transplant lymphoproliferative disorders (PTLD), a group of potentially devastating diseases that present on a spectrum of severity ranging from nondestructive PTLD to more histologically destructive lesions. Currently, there is inadequate evidence to guide evaluation and management of nondestructive PTLD. This is a single-center case series of pediatric kidney transplant recipients between January 1, 2008 and December 31, 2019, who were diagnosed with PTLD. The aim was to describe clinical characteristics, presentation, and management of nondestructive versus advanced PTLD. Eighteen patients were diagnosed with nondestructive PTLD and seven with more advanced PTLD histopathology. The majority (66.7%) of nondestructive PTLD patients (n=16) presented with tonsillar hypertrophy and/or snoring and were managed conservatively, with minimal reduction in tacrolimus dose and no further evaluation. No patient progressed to more advanced PTLD. Advanced PTLD patients (n=7) were more likely to present with fever, elevated creatinine, a new mass of gastrointestinal symptoms. They received workup with imaging and oncology consultation, and were managed with chemotherapy. Patients with nondestructive PTLD often present with symptoms of sleep-disordered breathing and can be managed conservatively with excellent clinical outcomes. More study is needed to guide care of this under-researched population.

Incidence and mortality of post-transplant lymphoproliferative disorders after kidney transplantation: A real-world retrospective analysis in Japan.

Post-transplant lymphoproliferative disorder is a potentially life-threatening complication that has a greater risk of occurrence in the setting of immunosuppression and oncogenic viral infections after transplant surgery. Few studies have reported the cumulative incidence, histological subtypes and clinical outcomes of this disorder in kidney transplant recipients. We retrospectively investigated 34 post-transplant lymphoproliferative disorder patients diagnosed out of the 1210 kidney transplant recipients who had undergone the surgery at the two largest centers in Japan between January 1983 and December 2017. A total of 32 patients (94.1%) developed late-onset post-transplant lymphoproliferative disorder (diagnosed 1year after transplantation). The cumulative incidence rates were 0.76% and 1.59% at 5 and 10years post-transplantation, respectively. The central nervous system was the most common site (35.3%, 12/34). Overall survival was similar between patients with and without central nervous system lesions (P=0.676). Of all of the cases, 23.5% (8/34) were detected through cancer screening. Importantly, patients with screening-detected post-transplant lymphoproliferative disorder had better overall survival than those with the disorder who had been symptom detected (P=0.0215). Overall survival was significantly reduced in patients who developed the disorder compared with those who did not (P=0.0001). Post-transplant lymphoproliferative disorder was more likely to occur in the late post-transplantation period, which showed that long-term medical examination for transplant recipients is required. Based on our findings, we propose vigilant, long-term, cancer screening in kidney transplant recipients.

Effect of preoperative long-term use of corticosteroids on the development of post-transplant lymphoproliferative disorders after lung transplantation: a single-center experience in Japan.

Post-transplant lymphoproliferative disorder (PTLD) is a major complication of lung transplantation (LTx). However, few studies on PTLD in Asian populations have been reported. We explored the characteristics of Japanese PTLD cases after LTx. We retrospectively reviewed 195 cases of LTx at our institute. We summarized the clinical experiences of 7 PTLD cases and analyzed the patient characteristics and survival outcomes of patients with (n = 7) and without (n = 188) PTLD. All PTLD patients were taking corticosteroids preoperatively (p = 0.0030), and the duration of preoperative corticosteroid therapy was significantly longer in the PTLD group (p = 0.0064) than in the non-PTLD group. The overall survival after LTx was significantly worse in the PTLD group (p = 0.027) than in the non-PLTD group. Among the three patients who died within 1year after the PTLD onset, two died of opportunistic infections without residual PTLD lesions. Chronic lung allograft dysfunction (CLAD) or bronchiolitis obliterans at an autopsy were diagnosed after PTLD treatment in four cases. Long-term preoperative corticosteroid therapy may be a risk factor for PTLD after LTx. Opportunistic infections are lethal complications of PTLD, regardless of the effectiveness of PTLD treatment. CLAD occurs at a high rate after PTLD treatment, and close monitoring is required.

Clinicopathologic Characteristics, Treatment, and Outcomes of Post-transplant Lymphoproliferative Disorders: A Single-institution Experience Using 2017 WHO Diagnostic Criteria.

The World Health Organization Classification of Tumours of Haematopoietic and Lymphoid Tissues (WHO 2017) included updated criteria for diagnosis and classification of post-transplant lymphoproliferative disorders (PTLDs). This study evaluated the clinicopathologic spectrum using WHO 2017 criteria and adult PTLD patients’ outcomes over 30 years between 1987 and 2017 at Mayo Clinic (Rochester, MN). Patients were retrospectively reviewed for clinical features, outcomes, and diagnostic pathology material and classified based on WHO 2017 criteria. A total of 227 patients were diagnosed with PTLD, with a median time from transplant to PTLD of 45 months. PTLD occurred >1 year after transplant in 149 (66%) patients. Monomorphic PTLD was the most common subtype (173, 76%), with diffuse large B cell lymphoma as the commonest morphology (n = 137). Epstein-Barr virus was positive in 61% of total cases and 90% of PTLD that developed within 1 year from transplant. The median event-free survival (EFS) and overall survival for the entire cohort were 21 months (95% confidence interval [CI]: 9–35) and 82 months (95% CI: 39–115), respectively. The EFS or overall survival was not impacted by Epstein-Barr virus status but differed based on WHO subtypes and year of diagnosis. Management changed over time with increased use of rituximab or chemotherapy + immunosuppression reduction as initial therapy. When compared to the matched general population and de novo diffuse large B cell lymphoma, patients not achieving EFS 24 status (no progression/treatment or death within 24 mo of diagnosis) had a worse standardized mortality ratio 16.75 (95% CI: 13.91–20) versus SMR 1.72 (95% CI: 1.26–2.28) in those who achieved EFS24. Cause of death was mostly attributed to non-lymphoma–related causes in those achieving EFS 24.