Failure of rituximab is associated with a poor outcome in diffuse large B cell lymphoma‐type post‐transplant lymphoproliferative disorder

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

BACKGROUND

Besides 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.

RESULTS

A 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.

CONCLUSION

CLIP is a promising predictor of PFS and perhaps OS in PTLD. Further prospective studies are needed to confirm these results.

Multicenter study of pediatric Epstein-Barr virus-negative monomorphic post solid organ transplant lymphoproliferative disorders

BACKGROUND

Pediatric Epstein-Barr virus-negative monomorphic post solid organ transplant lymphoproliferative disorder [EBV(-)M-PTLD] comprises approximately 10% of M-PTLD. No large multi-institutional pediatric-specific reports on treatment and outcome are available.

METHODS

A multi-institutional retrospective review of solid organ recipients diagnosed with EBV(-)M-PTLD aged ≤21 years between 2001 and 2020 in 12 centers in the United States and United Kingdom was performed, including demographics, staging, treatment, and outcomes data.

RESULTS

Thirty-six patients were identified with EBV(-)M-PTLD. Twenty-three (63.9%) were male. Median age (range) at transplantation, diagnosis of EBV(-)M-PTLD, and interval from transplant to PTLD were 2.2 years (0.1-17), 14 years (3.0-20), and 8.5 years (0.6-18.3), respectively. Kidney (n = 17 [47.2%]) and heart (n = 13 [36.1%]) were the most commonly transplanted organs. Most were Murphy stage III (n = 25 [69.4%]). Lactate dehydrogenase was elevated in 22/34 (64.7%) and ≥2 times upper limit of normal in 11/34 (32.4%). Pathological diagnoses included diffuse large B-cell lymphoma (n = 31 [86.1%]) and B-non-Hodgkin lymphoma (B-NHL) not otherwise specified (NOS) (n = 5 [13.9%]). Of nine different regimens used, the most common were: pediatric mature B-NHL-specific regimen (n = 13 [36.1%]) and low-dose cyclophosphamide, prednisone, and rituximab (n = 9 [25%]). Median follow-up from diagnosis was 3.0 years (0.3-11.0 years). Three-year event-free survival (EFS) and overall survival (OS) were 64.8% and 79.9%, respectively. Of the seven deaths, six were from progressive disease.

CONCLUSIONS

EFS and OS were comparable to pediatric EBV(+) PTLD, but inferior to mature B-NHL in immunocompetent pediatric patients. The wide range of therapeutic regimens used directs our work toward developing an active multi-institutional registry to design prospective studies.

PLAIN LANGUAGE SUMMARY

Pediatric Epstein-Barr virus-negative monomorphic post solid organ transplant lymphoproliferative disorders (EBV(-)M-PTLD) have comparable outcomes to EBV(+) PTLD, but are inferior to diffuse large B-cell lymphoma in immunocompetent pediatric patients. The variety of treatment regimens used highlights the need to develop a pediatric PTLD registry to prospectively evaluate outcomes. The impact of treatment regimen on relapse risk could not be assessed because of small numbers. In the intensive pediatric B-non-Hodgkin lymphoma chemoimmunotherapy group, 11 of 13 patients remain alive in complete remission after 0.6 to 11 years.

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

INTRODUCTION

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.

METHODS

TIL density (CD3+ cells/mm²) was determined by CD3 immunohistochemistry in archived diagnostic biopsies from patients diagnosed with monomorphic B-cell PTLD.

RESULTS

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).

CONCLUSIONS

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.

Modified risk-stratified sequential treatment (subcutaneous rituximab with or without chemotherapy) in B-cell Post-transplant lymphoproliferative disorder (PTLD) after Solid organ transplantation (SOT): the prospective multicentre phase II PTLD-2 trial

The prospective multicentre Phase II PTLD-2 trial (NCT02042391) tested modified risk-stratification in adult SOT recipients with CD20-positive PTLD based on principles established in the PTLD-1 trials: sequential treatment and risk-stratification. After rituximab monotherapy induction, patients in complete remission as well as those in partial remission with IPI < 3 at diagnosis (low-risk) continued with rituximab monotherapy and thus chemotherapy free. Most others (high-risk) received R-CHOP-21. Thoracic SOT recipients who progressed (very-high-risk) received alternating R-CHOP-21 and modified R-DHAOx. The primary endpoint was event-free survival (EFS) in the low-risk group. The PTLD-1 trials provided historical controls. Rituximab was applied subcutaneously. Of 60 patients enrolled, 21 were low-risk, 28 high-risk and 9 very-high-risk. Overall response was 45/48 (94%, 95% CI 83–98). 2-year Kaplan–Meier estimates of time to progression and overall survival were 78% (95% CI 65–90) and 68% (95% CI 55–80) – similar to the PTLD-1 trials. Treatment-related mortality was 4/59 (7%, 95% CI 2–17). In the low-risk group, 2-year EFS was 66% (95% CI 45–86) versus 52% in the historical comparator that received CHOP (p = 0.432). 2-year OS in the low-risk group was 100%. Results with R-CHOP-21 in high-risk patients confirmed previous results. Immunochemotherapy intensification in very-high-risk patients was disappointing.

Incidence and outcomes of post-transplant lymphoproliferative disease after 5365 solid-organ transplants over a 20-year period at two UK transplant centres

Post-transplant lymphoproliferative disease (PTLD) is a life-threatening complication of solid-organ transplantation (SOT). We present the incidence and outcomes of PTLD in a cohort of 5365 SOT recipients over a 20-year period at two UK transplant centres. With a median follow-up of 7.7 years, 142 of 5365 patients have developed PTLD. Cumulative incidence was 18% at five years after multivisceral transplant and 1%-3% at five years following the other SOT types. Twenty-year cumulative incidence was 2%-3% following liver and heart transplantation and 10% following kidney transplantation. Median overall survival (OS) following SOT was 16 years, which is significantly reduced compared with the age-adjusted UK population. There is relatively high early mortality following diagnosis of PTLD and only patients surviving two years regained a longer-term survival approaching the non-PTLD SOT cohort. Of 90 patients with monomorphic PTLD, diffuse large B-cell lymphoma, 66 were treated with first-line rituximab monotherapy and 24 received first-line rituximab plus chemotherapy. Up-front rituximab monotherapy does not appear to compromise OS, but the number of patients dying from non-lymphoma causes before and after treatment remains high with both treatment approaches. Multivariate analysis of all 90 monomorphic PTLD patients identified an International Prognostic Index (IPI) of 3+ as the strongest pretreatment variable associating with inferior one-year OS.

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

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

CAR-T therapy in solid transplant recipients with post-transplant lymphoproliferative disease: case report and literature review

Patients with postransplant lymphoproliferative disease (PTLD) who are refractory to rituximab-based regimens have extremely poor prognosis. Data is lacking in the setting of solid organ transplantation (SOT)-related PTLD treated with chimeric antigen receptor T-cell (CAR-T) therapy. Moreover, limited information is available on the influence of concomitant immunosuppressive drugs on CAR-T function. Here, we describe the clinical outcome in one PTLD patient and propose a strategy for tailoring immunosuppressive treatment and organ monitoring in patients with kidney allografts after CAR-T infusion. This report also reviews the limited published data in the setting of SOT-related PTLD treated with CAR-T, which appears to be a feasible treatment in this clinical scenario, without severe toxicity and capable of inducing sustained responses. A noteworthy finding is that in most reported cases patients underwent complete or partial discontinuation of immunosuppressive drugs, with only one documented case of allograft rejection.

Clinical features and treatment strategies for post-transplant and iatrogenic immunodeficiency-associated lymphoproliferative disorders

A specific category termed immunodeficiency-associated lymphoproliferative disorders (LPD) exists in the 2016 revised WHO classification concerning lymphoid neoplasms. This category is defined by etiology and includes LPD developing in association with organ transplantation or immunosuppressive/immunomodulatory agents including methotrexate. The functional mechanism is chiefly explained by the autonomous proliferation of Epstein-Barr virus (EBV)-infected lymphocytes induced by host-immune suppression. This category ranges from reactive lymphocyte hyperplasia to monomorphic lymphoma. Its clinical behavior varies depending on host immunity and pathological features; pathological confirmation by biopsy is thus important for deciding treatment strategies. Owing to the spontaneous regression observed in some patients, uniform chemotherapy is not recommended. The main initial treatment options include the reduction in immunosuppressive drugs, immunotherapy with the anti-CD20 antibody rituximab, chemotherapy, or a combination of these. Other novel treatments such as adoptive immunotherapy with EBV-specific cytotoxic T cells, could be an alternative for relapsed/refractory diseases in clinical trials.

Anti-CD19 CAR-T therapy for EBV-negative posttransplantation lymphoproliferative disease-a single center case series

Posttransplantation lymphoproliferative disease (PTLD) is a potentially fatal disorder arising after solid organ or hematopoietic cell transplantation. Survival rates of PTLD with diffuse large B-cell lymphoma (DLBCL) phenotype have improved due to the introduction of rituximab, however, reports on curative management of refractory PTLD are scarce. Here, we describe successful management of three patients with refractory EBV-negative PTLD with chimeric antigen receptor T-cell (CAR-T) therapy. All patients continued calcineurin inhibitors throughout the whole course of treatment. T-cell immunophenotyping was performed on both the apheresed cells and CAR-T product to investigate the T-cell compartment subpopulations. All three patients responded to a single infusion of tisagenlecleucel and two of them achieved CR. Toxicity profile was similar to other patients with non-PTLD DLBCL treated with CAR-T. No transplanted graft dysfunction was observed during the course of therapy. To our knowledge, this is the first report demonstrating that patients with EBV-negative refractory PTLD may benefit from CAR-T therapy, similarly to other patients with relapse/refractory DLBCL. A larger cohort of patients is needed to further establish proof-of-concept.