Post-transplant Lymphoproliferative Disorder Research Articles

Clinical Analysis of Epstein-Barr Virus Infection after Allogeneic Hematopoietic Stem Cell Transplantation

To analyze the risk factors of Epstein-Barr virus (EBV) infection after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and its impact on survival. The clinical data of 347 patients who underwent their first allo-HSCT in our hospital from January 2014 to June 2021 were retrospectively analyzed. Patients were divided into EBV (n =114) and Non-EBV (n =233) groups according to whether they were infected with EBV. The incidence of EBV infection after allo-HSCT was calculated, and the risk factors of EBV infection were analyzed. A total of 114(32.8%) patients presented EBV infection (all peripheral blood EBV-DNA were positive). EBV infection occurred in 88 patients within 100 days after transplantation, which accounted for 77.2% of all patients with EBV infection. 5 cases (1.44%) were confirmed as post-transplant lymphoproliferative disorder (PTLD). The median onset time of patients was 57(7-486) days after transplantation. Multivariate analysis showed that the use of ATG/ATG-F, occurrence of CMV viremia, and grade III-IV aGVHD were risk factors for EBV infection. Furthermore, compared to BUCY, the use of intensified preconditioning regimens containing FA/CA was significantly increased the risk of EBV infection. EBV infection is a common complication after allo-HSCT. Intensified preconditioning regimens, use of ATG/ATG-F, CMV viremia and grade III to IV aGVHD increase the risk of EBV infection after allo-HSCT.

Diagnosis and Treatment of Skin Lesions in Renal Transplant Recipients: A Retrospective Review.

Immunosuppressive therapy is essential for to prevent graft rejection in renal transplant patients; however, it is associated with elevating the risk of several pathologies in these patients particularly infectious and neoplastic conditions. In this study, we explore the diagnosis and treatment of skin lesions in renal transplant patients. A retrospective chart review of 12 renal transplant recipients referred to plastic and reconstructive surgery with skin lesions from 2000 to 2020 was performed. The mean age of the 12 patients was 49.6 years. Time to plastic surgery after renal transplantation ranged between 1 and 16 years. Nine cases of basal cell carcinoma, 2 cases of squamous cell carcinoma, and 1 case of skin and soft tissue infection of the lower extremity and cutaneous extranodal NK/T-cell lymphoma, nasal type was observed. Flaps, skin grafts, and artificial dermis grafts constitute the main reconstructive methods. There were no postoperative infections or wound dehiscence. Cutaneous infections and skin malignancy account for most of the skin lesions developing after renal transplantation. Posttransplant lymphoproliferative disorder warrants equal attention and should not be disregarded. Early diagnosis and treatment significantly improve prognosis as patients with longer duration of transplant were found to have more aggressive tumors. Plastic and reconstructive surgery offers a safe therapeutic method of treatment in these cases.

Epstein-Barr virus-positive post-transplant lymphoproliferative disease: results of a Delphi study in Spain

Epstein-Barr virus-positive post-transplant lymphoproliferative disease: results of a Delphi study in Spain

Admissions for posttransplant lymphoproliferative disorder: a 9-year longitudinal analysis of the National (Nationwide) Inpatient Sample

Background Posttransplant lymphoproliferative disorder (PTLD), a term that encompasses a wide array of malignancies that occur after transplant, can be one of the most devastating transplant complications. While there have been major advancements in care, especially after the landmark PTLD-1 trial in 2012, there is a paucity of information on hospitalizations for PTLD and the changes in hospitalizations over time. Methods This retrospective cohort study used the National Inpatient Sample to identify hospitalizations for PTLD that occurred between 2009 and 2018. We extracted data for hospitalizations with a primary or secondary diagnosis of PTLD and examined a range of variables, including age, gender, race, hospital type, hospital location, and disposition status. We also collected data on hospital region, median household income, insurance status, and bed size. Results There was a statistically significant increase in the number of hospitalizations from 2009 to 2019 and an increasing rate of hospitalizations over the study period. Hypertension, electrolyte imbalances, renal failure, and anemia were among the most common comorbidities. We found an increased mortality rate, but this was not statistically significant. Conclusion Our study provides insight into the changes in hospitalizations for PTLD over nearly a decade, showing an increase in hospitalizations and reports of comorbidities.

Clinical epidemiology of Epstein-Barr virus-associated Lymphoproliferative Disorders (EBV-LPDs) in hospitalized children: A six-year multi-institutional study in China

BackgroundEpstein-Barr virus-associated lymphoproliferative disorders (EBV-LPDs) are a group of disorders involving lymphoid tissues or lymphocytes. The epidemiology and economic burden of hospitalized children with EBV-LPDs in China have not been well studied. This study aimed to reveal the epidemic characteristics and disease burden of EBV-LPDs among the Chinese hospitalized children, providing strategies for the prevention and management.MethodsThis study was based on the FUTang Updating medical REcords (FUTURE) database of China and collected the medical records from 27 tertiary children’s hospitals between January 2016 and December 2021 in China, counting five types of EBV-LPDs, namely EBV-positive T-cell lymphoproliferative disease, NK/T cell lymphoma, extranodal NK/T-cell lymphoma (nasal type), systemic EBV-positive T-cell lymphoproliferative disease of childhood and posttransplant lymphoproliferative disorders. We conducted a retrospective syhthesis and analysis of the epidemiological characteristics, expenses, length of stay (LOS), as well as complications among hospitalized children diagnosed with five types of EBV-LPDs and compared parameters using appropriate statistical tests.ResultsThe study described 153 children aged 0–18 years hospitalized with EBV-LPDs from 2016 to 2021 in the FUTURE database. The male-to-female ratio was 1.10:1, and more than half of the age distribution was in the 6–12 y group. Among EBV-LPDs cases, EBV+ T-LPD accounted for the largest proportion (65.36%). Complications were presented in 93 children with EBV-LPDs, mainly hemophagocytic lymphohistiocytosis (HLH). The median LOS of NKTL was 26.5 days [interquartile range (IQR) = 3–42], which was the longest among EBV-LPDs. The median hospitalization cost of PTLD was 10 785.74 United States dollars (IQR = 7 329.38–16 531.18), which was the heaviest among EBV-LPDs.ConclusionsCompared with the total number of hospitalized children in China during the same period and in the same age group, the proportion of EBV-LPD is very low. EBV-LPD can develop in all age groups, but it is more common in school-age children. Among 5 EBV-LPDs, the disease with the highest proportion is EBV+ T-LPD. The overall disease burden of EBV-LPD was heavy, especially the economic burden. HLH was one of the most common complications, which could directly affect the burden of patients because of prolonged hospitalization. These data are taken from a very large database, illustrating the epidemiological and economic burden of EBV-LPDs hospitalized children in China, which enriched the existing epidemiological and disease burden content of EBV-LPDs.

Cytokine Dynamics and Herpesvirus Interactions in Pediatric Liver and Kidney Transplant Recipients: The Distinct Behavior of HCMV, HHV6, HHV7 and EBV.

Pediatric solid organ transplant (SOT) recipients face a challenging balance between immunosuppression and graft rejection. While Epstein-Barr Virus (EBV) and cytomegalovirus (HCMV) are known contributors to post-transplant lymphoproliferative disease and graft rejection, respectively, the roles of herpesvirus 6 and 7 (HHV6 and HHV7) and the impact of these herpesviruses on cytokine levels remain unclear, leading to gaps in clinical practice. In this associative study, we measured 17 cytokines using a Bio-Plex assay in a meticulously curated plasma sample pool (N = 158) from pediatric kidney and liver transplant recipients over a one-year follow-up period. The samples included virus-negative and virus-positive cases, either individually or in combination, along with episodes of graft rejection. We observed that the elevation of IL-4, IL-8, and IL-10 correlated with graft rejection. These cytokines were elevated in samples where HCMV or HHV6 were detected alone or where EBV and HHV7 were co-detected. Interestingly, latent EBV, when detected independently, exhibited an immunomodulatory effect by downregulating cytokine levels. However, in co-detection scenarios with β-herpesviruses, EBV transitioned to a lytic state, also associating with heightened cytokinemia and graft rejection. These findings highlight the complex interactions between the immune response and herpesviruses in transplant recipients. The study advocates for enhanced monitoring of not only EBV and HCMV but also HHV6 and HHV7, providing valuable insights for improved risk assessment and targeted interventions in pediatric SOT recipients.

EBV T-cell immunotherapy generated by peptide selection has enhanced effector functionality compared to LCL stimulation.

Adoptive immunotherapy with Epstein-Barr virus (EBV)-specific T cells is an effective treatment for relapsed or refractory EBV-induced post-transplant lymphoproliferative disorders (PTLD) with overall survival rates of up to 69%. EBV-specific T cells have been conventionally made by repeated stimulation with EBV-transformed lymphoblastoid cell lines (LCL), which act as antigen-presenting cells. However, this process is expensive, takes many months, and has practical risks associated with live virus. We have developed a peptide-based, virus-free, serum-free closed system to manufacture a bank of virus-specific T cells (VST) for clinical use. We compared these with standard LCL-derived VST using comprehensive characterization and potency assays to determine differences that might influence clinical benefits. Multi-parameter flow cytometry revealed that peptide-derived VST had an expanded central memory population and less exhaustion marker expression than LCL-derived VST. A quantitative HLA-matched allogeneic cytotoxicity assay demonstrated similar specific killing of EBV-infected targets, though peptide-derived EBV T cells had a significantly higher expression of antiviral cytokines and degranulation markers after antigen recall. High-throughput T cell receptor-beta (TCRβ) sequencing demonstrated oligoclonal repertoires, with more matches to known EBV-binding complementary determining region 3 (CDR3) sequences in peptide-derived EBV T cells. Peptide-derived products showed broader and enhanced specificities to EBV nuclear antigens (EBNAs) in both CD8 and CD4 compartments, which may improve the targeting of highly expressed latency antigens in PTLD. Importantly, peptide-based isolation and expansion allows rapid manufacture and significantly increased product yield over conventional LCL-based approaches.

Recurrent Pleural Effusion Associated With Candida Albicans Infection in Transplanted Kidney: A Case Report

Recurrent pleural effusions are associated with significant morbidity and mortality. Pleural effusions are well known in chronic renal failure patients due to fluid retention. Pleural effusions in renal transplant patients are usually related to secondary pulmonary infections, surgical complications, drug toxicities and post-transplant lymphoproliferative disorder (PTLD). We describe an unusual cause of recurrent pleural effusion attributed to fungal infection in transplanted kidney due to activation of renin-angiotensin-aldosterone system (RAAS), successfully treated with antifungal medications that lead to complete resolution of pleural effusion.

Evaluation of anti-vector immune responses to adenovirus-mediated lung gene therapy and modulation by αCD20

Although the last decade has seen tremendous progress in drugs that treat cystic fibrosis (CF) due to mutations that lead to protein misfolding, there are approximately 8%-10% of subjects with mutations that result in no significant CFTR protein expression demonstrating the need for gene editing or gene replacement with inhaled mRNA or vector-based approaches. A limitation for vector-based approaches is the formation of neutralizing humoral responses. Given that αCD20 has been used to manage post-transplant lymphoproliferative disease in CF subjects with lung transplants, we studied the ability of αCD20 to module both T and B cell responses in the lung to one of the most immunogenic vectors, E1-deleted adenovirus serotype 5. We found that αCD20 significantly blocked luminal antibody responses and efficiently permitted re-dosing. αCD20 had more limited impact on the Tcell compartment, but reduced tissue resident memory Tcell responses in bronchoalveolar lavage fluid. Taken together, these pre-clinical studies suggest that αCD20 could be re-purposed for lung gene therapy protocols to permit re-dosing.

CD56bright NK cell expansion correlated with EBV reactivation control post allogeneic hematopoietic stem cell transplantation.

Natural killer (NK) cells are equipped with anti-Epstein-Barr virus (EBV) function, however, whether EBV infection will affect NK cells reconstitution after allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains unclear. To identify the characteristics of NK cells, we prospectively enrolled 11 patients who occurred EBV reactivation post allo-HSCT and 11 patients without EBV infection as control. We found that that EBV infection induced the expansion of CD56bright and NKG2A+KIR- NK subsets,and decreased the cytotoxicity function of NK cells. The frequency of NKG2A+KIR- NK cells were higher in patients who progressed into post-transplant lymphoproliferative disorder (PTLD) than EBV viremia patients, which also correlated with decreased proliferation and cytotoxic function. By screening the activation receptors of NK cells, we found the DNAM-1+CD56bright NK cells is significantly increased after EBV stimulation, further we demonstrated that DNAM-1 is essential for EBV induced NK cells activation as the cytokine release against EBV-transformed lymphoblastoid cell lines(EBV-LCLs) of CD56bright NK cells were significantly decreased after DNAM-1 blockade. NK cells infusion suppressed the progression of EBV-related tumor mice model. A prospective cohort indicated that old donor age was an independent risk factor for EBV infection. Rapid CD56bri expansion and high expression of DNAM-1 on CD56bri NK cells in response to EBV reactivation correlated with rapid EBV clearance post allo-HSCT in patients with younger donors. In summary, our data showed that high expression of DNAM-1 receptors on NK cell may participate protective CD56bri NK cells response to EBV infection after allo-HSCT.

Chronological alterations in de novo malignancies after living-donor liver transplantation: A cohort study of 1781 recipients using annual comparisons of standardized incidence ratios.

De novo malignancies (DNMs) are a major adverse event after solid organ transplantation; however, their characteristics and recent trends after living-donor liver transplantation (LDLT) remain unclear. We retrospectively reviewed 1781 primary LDLT recipients (1990-2020) and annually calculated standardized incidence ratios (SIRs) of DNMs compared to the age-adjusted Japanese general population. After 21 845 person-years follow-up, 153 DNM lesions (8.6%) were identified in 131 patients (7.4%). The incidence was 0.007 person-years. DNMs included 81 post-transplant lymphoproliferative disorders (PTLDs), 14 colorectal, 12 lung, and 12 gastric cancers, and so on. Comorbid DNMs significantly worsened recipient survival than those without (p < .001). The 5- and 10-year recipient survival after DNM diagnosis were 65% and 58%, respectively. Notably, SIR1993-1995: 8.12 (95% CI: 3.71-15.4, p < .001) and SIR1996-1998: 3.11 (1.34-6.12, p = .01) were significantly high, but had decreased time-dependently to SIR2005-2007: 1.31 (0.68-2.29, p = .42) and SIR2008-2010: 1.34 (0.75-2.20, p = .33), indicating no longer significant difference in DNMs development. Currently, however, SIR2014-2016: 2.27 (1.54-3.22, p < .001) and SIR2017-2019: 2.07 (1.40-2.96, p < .001) have become significantly higher again, reflecting recent aging of recipients (>50 years) and resultant increases in non-PTLD DNMs. Furthermore, characteristically in LDLT, the fewer the donor-recipient HLA-mismatches, the less the post-transplant DNMs development. DNM development after LDLT was significantly higher than in the general population due to higher PTLD incidence (1993-1998), but once became equivalent (2005-2013), then significantly increased again (2014-2019) due to recent recipient aging and resultant increase in solid cancers.

Incidence, characteristics and outcomes in relapsed and refractory CD20+ PTLD: An institutional retrospective cohort study.

e19078 Background: Post-transplant lymphoproliferative disorder (PTLD) is a malignancy with significant morbidity and mortality after solid organ transplant (SOT). Frontline treatment of CD20+ PTLD is well established; however, there is a lack of data on the treatment of relapsed/refractory (R/R) PTLD, especially in the era of novel therapies approved since 2017 for diffuse large B-cell lymphoma. Methods: We conducted a single institution retrospective study of adult SOT patients with CD20+ PTLD. Inclusion criteria were age ≥18 and use of an adult regimen that included rituximab for frontline therapy. Baseline and pathologic characteristics, frontline and subsequent treatments, response rates, and toxicities were collected. Results: 71 cases of CD20+ PTLD were diagnosed between 01/01/2012 to 12/31/2022. The median age at diagnosis was 46. SOTs included kidney (46.5%), liver (21.1%), lung (16.9%), heart (14.1%), and pancreas (1.4%). Pathologically, 47 cases were monomorphic (12 germinal center B-cell-like [GCB] subtype, 26 non-GCB subtype, 9 cases indeterminate), 12 were polymorphic, 2 were non-destructive, and 10 were unclassified. 38 cases (53.5%) were Epstein-Barr virus positive. Frontline treatments included rituximab followed by R-CHOP (38.0%), rituximab monotherapy (16.9%), R-EPOCH (4.2%), and R-miniCHOP (2.8%). Toxicities included acute kidney injury (21.1%) and perforation (9.8%) and rejection (7%). The median overall survival (OS) was 62 months. 21 (29.6%) patients relapsed (N = 13) or were refractory (N = 8) to frontline treatment. Median time to relapse was 12.0 months. Systemic treatments included RCHOP, R-miniCHOP, RICE, R-Gemcitabine and oxaliplatin (R-GemOx), lenalidomide/tafasitamab (len/tafa), and R-ibrutinib with an overall response rate (ORR) of 72.2% in the second line setting; 50% of patients required dose reductions. Median OS was 17 months. Progression-free survival (PFS) was 4.5 months. The. ORR, median PFS and OS among those who received novel therapy (N=3) was 100%, 4.4 months, and not reached compared to 66.7%, 8 months, and 4.6 months with traditional cytotoxic therapy (N=15), respectively. 6 patients received a third line of therapy, which included polatuzumab-BR, CAR-T cell therapy, R-GemOx, len/tafa, and loncastuximab. ORR was 80%. 33% of patients required dose reductions. At data cutoff, 2 patients who received a third line of therapy were alive with stable disease on therapy. Causes of death in third line treatment included perforation (N=1), COVID (N = 1), fungemia (N=1), and cardiac arrest likely unrelated to PTLD (N = 1). 3 patients who died had active PTLD at time of death. No patients experienced graft rejection during treatment for R/R PTLD. Conclusions: R/R CD20+ PTLD after SOT remains a therapeutic challenge. Better understanding of cytotoxic versus novel therapies can help guide clinical decision making.

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.

Extramedullary plasmacytoma exclusively localized in transplanted kidney: Post-transplant lymphoproliferative disorder or monoclonal gammopathy of renal significance?

Post-Transplant Lymphoproliferative Disease (PTLD) is defined as a malignancy that occurs post solid organ transplant (SOT). The incidence of PTLD in kidney transplant is lowest amongst all SOT with a majority having a monomorphic pattern that is commonly B cell driven. Plasmacytic variants of PTLD have been rarely reported, with only a handful of cases being clonal in nature. Here we report a unique case of a plasmacytoma-like PTLD with IgG-K restriction confined entirely to the kidney allograft, without evidence of any clonal plasma cell in the bone marrow or other extramedullary site. This case highlights an extremely rare disease, describes a diagnostic dilemma, reports the unconventional management, and poses more interesting questions about the pathophysiology of this disease.

Long-term outcomes after cardiac transplantation in AL amyloidosis.

7572 Background: Systemic AL amyloidosis can lead to progressive multi-organ dysfunction including advanced heart failure which may require orthotopic heart transplantation (OHT). Hematologic outcomes of AL amyloidosis post-OHT are not well described. Methods: We report outcomes for patients with AL amyloidosis with cardiac involvement post-OHT from Nov 2008 - Jun 2023 at Vanderbilt University Medical Center. Hematologic response was graded per the ISA guidelines. Results: Fourteen pts underwent OHT of whom 13 had lambda light chain disease. Three (21%) pts had isolated AL amyloidosis (AL) without myeloma (MM), while 11 (79%) also had MM: 6 with bone marrow plasma cells (BMPCs) 10-19% (AL-PCMM-10) and 5 with BMPC ≥20% (AL-PCMM-20). One each with AL-PCMM-10 and AL-PCMM-20 had lytic lesions (AL-CRAB). Median age at OHT was 55.5 yrs (range 37-74). Median time from diagnosis to OHT was 18 mo (range 3-62). Five (35%) pts had biopsy-proven extracardiac amyloid involvement. Median difference in serum free light chains at first evaluation was 70 mg/dL (range 9-289). Three pts were Mayo 2012 stage II, 4 stage III, and 7 stage IV. Four pts had t(11;14) and 1 had 1q gain. Ten (71%) pts received triplet therapy (VCd or VRd) and 3 (21%) received quadruplet therapy (Dara-VCd or Isa-VCd) pre-OHT. Six (43%) pts had autologous stem cell transplantation (ASCT); 1 pre-OHT and 5 post-OHT. Of ASCT pts, 1 pt achieved CHR, 1 VGPR, 2 PR, and 1 had PD pre-ASCT. Pre-OHT, 4 pts achieved CHR, 6 VGPR, 3 PR, and 1 had PD. Eleven pts (79%) received maintenance therapy post-OHT (5 proteosome inhibitors, 6 anti-CD38). At last follow-up, 8 pts were in CHR, 3 in VGPR, 1 in PR, and 2 had PD. Four (29%) pts died post-OHT: 2 from AL recurrence (1 each with AL and AL-PCMM-10), 1 from cardiac allograft vasculopathy (AL-CRAB), and 1 from renal failure (AL-CRAB). Three (21%) pts had hematologic relapse 5, 21 and 48 mo post-OHT, and of those, 2 had recurrent cardiac amyloid in graft 37 and 71 mo post-OHT. Of those with hematologic relapse, 2 had AL-PCMM-10 and 1 had AL. One pt had post-transplant lymphoproliferative disorder 126 mo post-OHT, requiring treatment. Median follow-up and survival of the cohort post-OHT was 2.25 yrs (range 0.5-13.8). Conclusions: In this single-center analysis of pts undergoing OHT for cardiac AL amyloidosis, we demonstrate feasibility of excellent long-term outcomes, in predominantly high-risk AL pts where majority harbored high-risk disease with MM overlap, either by AL-CRAB or AL-BMPC. Induction alone led to ≥VGPR response in 10 (71%) pts pre-OHT and further therapy deepened this to 11 (79%) pts. Both AL-CRAB pts died during follow-up, highlighting the overall poor prognosis in this specific subgroup. In our cohort, non-relapse related mortality was seen in only 2 (14%) pts, demonstrating acceptable post-OHT risk and overall ability to achieve far improved outcomes in the high-risk cardiac AL amyloidosis patient population that otherwise suffers from rapid and universal mortality.

The IPTA Nashville consensus conference on post-transplant lymphoproliferative disorders after solid organ transplantation in children: IV-consensus guidelines for the management of post-transplant lymphoproliferative disorders in children and adolescents.

The International Pediatric Transplant Association convened an expert consensus conference to assess current evidence and develop recommendations for various aspects of care relating to post-transplant lymphoproliferative disorders (PTLD) after pediatric solid organ transplantation. This report addresses the outcomes of deliberations by the PTLD Management Working Group. A strong recommendation was made for reduction in immunosuppression as the first step in management. Similarly, strong recommendations were made for the use of the anti-CD20 monoclonal antibody (rituximab) as was the case for chemotherapy in selected scenarios. In some scenarios, there is uncoupling of the strength of the recommendations from the available evidence in situations where such evidence is lacking but collective clinical experiences drive decision-making. Of note, there are no large, randomized phase III trials of any treatment for PTLD in the pediatric age group. Current gaps and future research priorities are highlighted.

Post-transplant lymphoproliferative disorder in a child after kidney transplantation: a case report

Post-transplant lymphoproliferative disorder in a child after kidney transplantation: a case report

Cerebellum/liver index on baseline 18F-FDG PET/CT to improve prognostication in post-transplant lymphoproliferative disorders: a multicenter retrospective study

BackgroundBesides International Prognostic Index (IPI) score, baseline prognostic factors of post-transplant lymphoproliferative disorders (PTLD) are poorly identified due to the rarity of the disease. New indexes derived from healthy organ uptake in baseline 18F-FDG PET/CT have been studied in immunocompetent lymphoma patients. The aim of this study is to evaluate the performances of the cerebellum-to-liver uptake ratio (denoted as CLIP) as a prognostic factor for PFS and OS. This retrospective multicenter study is based on patients with PTLD included in the K-VIROGREF cohort. The previously published threshold of 3.24 was used for CLIP in these analyses.ResultsA total of 97 patients was included with a majority of monomorphic diffuse large B-cell lymphoma subtype (78.3%). Both IPI score (≥ 3) and CLIP (< 3.24) were significant risk factors of PFS with corresponding hazard ratios of 2.0 (1.0–4.0) and 2.4 (1.3–4.5) respectively. For OS, CLIP was not significant and resulted in a hazard ratio of 2.6 (p = 0.059). Neither IPI score or Total Metabolic Tumor Volume reached significance for OS.ConclusionCLIP is a promising predictor of PFS and perhaps OS in PTLD. Further prospective studies are needed to confirm these results.

#2992 Risk and prognostic factors for post-transplantation lymphoproliferative disease in solid organ transplant recipients—a multicenter analysis

Abstract Background and Aims Post-transplantation lymphoproliferative disorder (PTLD), a potentially fatal complication of transplantation, affects solid organ transplant recipients at different rates, depending on organ graft type: the risk greater in lung transplant recipients (LngTRs), lower for liver transplant recipients (LTRs) and lowest for kidney transplant recipients (KTR). In this study we aimed to investigate the factors affecting the development and treatment outcomes of PTLD and compare their effect on KTRs, LTRs and LngTRs. Method In this retrospective cohort study we have included all KTRs, LTRs and LngTRs diagnosed with PTLD at six transplantation centers in Poland. The data collected from medical records included: immunosuppression (IS), viral infections, PTLD type, treatment and outcomes. Chi-squared test was used to assess the differences in group composition. To determine the impact of variables upon PTLD time of onset and patient survival, univariate Cox regression was used. p-values below 0.05 were considered statistically significant. Results We enrolled 50 KTRs, 36 LTRs and 5 LngTRs from 6 transplantation centers in Poland. Based on the data from the most contributing centers in each group, the prevalence of PTLD was 0.82% of KTRs, 2.03% LTRs and 1.51% of LngTRs. Two thirds of the enrolled patients were male, the median age at first transplantation was 40 years for KTRs, 45 for LTRs and 25 for LngTRs (Table 1). The groups significantly differed in IS treatment: steroid (GCS) and cyclosporin (CsA) use was more frequent in KTRs (p&amp;lt;0.001 and p&amp;lt;0.001 and respectively), tacrolimus (TAC) and anti-CD25 induction in LTRs (p ≤ 0.001 and p&amp;lt;0.001 respectively), sirolimus (RAPA) in LngTRs (p&amp;lt;0.001). KTRs were the latest to develop PTLD (126 months after transplantation, p&amp;lt;0.001). In all groups Monomorphic B-cell PTLD was the most frequent. Initial IS treatment reduction was used in 80-86% of patients, R-CHOP chemotherapy was most common in LTRs (p=0.021), other chemotherapy regimens in KTRs (p=0.031). TAC had the opposite effect on PTLD time of onset in KTRs (HR=2.18, p=0.013) and LTRs (HR=0.18, p=0.036). The overall survival at the end of observation period was 26% for KTRs, 58% for LTRs and 80% for LngTRs. Loss to follow up was most frequent in KTRs at 26%. Patient survival was not affected by PTLD treatment. Conclusion KTRs develop PTLD later than LTRs and LngTRs, and time of disease onset is associated with TAC use. Lower survival in KTRs may result from the longer follow-up period compared to other solid organ transplant recipients.

#99 Clinical characteristics and outcomes of PTLD after kidney transplant: a single center experience

Abstract Background and Aims Post-Transplant Lymphoproliferative Disorder (PTLD) is a serious and potentially fatal complication of immunosuppression in kidney transplantation. Given the rarity of this entity, a high index of suspicion is necessary. We aimed to review the incidence, clinical presentation, histological subtypes, treatment, patient and graft survival of PTLD in kidney transplant patients in our unit. Methods Observational retrospective study, including adults diagnosed with PTLD between 1998 and 2023 in a Kidney Transplantation Center. Results Of 1390 kidney transplant recipients, 4 (0.3%) developed PTLD with a mean age of 52 ± 12.5 years. All cases were late-onset, occurring one year after transplantation with a median time from transplantation to diagnosis of 16.7 ± 7.3 years (range: 5-22 years). Of these, none had EBV donor/recipient mismatch. Two patients had prior rejection episodes (one patient, acute T cell-mediated rejection and the other patient, acute T cell-mediated rejection and active antibody mediated rejection). Clinical presentation was variable. Non-specific constitutional symptoms such as fever, fatigue and night sweats were present in all patients. Organ-specific symptoms were also present: lumbar pain in one patient with bone involvement, and delirium and lethargy in two patients with central nervous system involvement. Laboratory analyses revealed an increase in serum LDH in all patients. The primary sites of involvement were central nervous system (50%), lymph nodes (25%) and bone (25%). At PTLD diagnosis, immunosuppression included: tacrolimus (100%), mycophenolate mofetil (75%), low-dose of steroids (50%) and everolimus (25%). Regarding histologic classification, 75% were monomorphic and 25% polymorphic. In the monomorphic group, all patients had Diffuse Large B Cell Lymphoma (CD20 positive). In the polymorphic group, the patient had a Mixed Cellularity Classic Hodgkin Lymphoma (CD20 negative). Immunosuppression therapy was reduced in all patients with discontinuation of mycophenolate mofetil and tacrolimus. In the patient who was taking everolimus, the dose was increased due to the potential clinical antitumor effects of mTOR inhibition. Additional therapies included, rituximab in monotherapy or in combination with chemotherapy (R-CHOP) in the monomorphic group. Palliative measures were selected for one patient of this group due to advanced disease. The patient with Mixed Cellularity Classic Hodgkin Lymphoma (CD20 negative) did chemotherapy with ABVD. None of the patients underwent surgery or radiation therapy. Two patients needed dialysis. Three patients died in the first four weeks after PTLD diagnosis, all due to infectious complications. Patient survival was 25% one year after diagnosis. Conclusions Although the incidence of PTLD was low following kidney transplantation, its impact was significant in kidney graft and overall patient survival. Given the poor prognosis, new therapies combining high efficacy and low toxicity are an urgent unmet medical need in this field.