Marginal zone lymphoma international prognostic index: a unifying prognostic index for marginal zone lymphomas requiring systemic treatment

Background

Marginal zone lymphomas (MZL), comprised of three unique but related subtypes, lack a unifying prognostic score applicable to all the patients in need for systemic chemotherapy and/or immunotherapy.

Methods

Patients from the prospective NF10 study (NCT02904577) with newly diagnosed MZL and receiving frontline systemic therapy at diagnosis or after observation were used to train a prognostic model. The primary endpoint was progression-free survival (PFS) from start of treatment. The model was externally validated in a pooled analysis of two independent cohorts from the University of Iowa and Mayo Clinic Molecular Epidemiology Resource and the University of Miami.

Findings

We identified 501 eligible patients. After multivariable modeling, lactate dehydrogenase (LDH) above upper normal limit, hemoglobin <12 g/dL, absolute lymphocyte count <1 × 109/L, platelets <100 × 109/L, and MZL subtype (nodal or disseminated) were independently associated with inferior PFS. The proposed MZL International Prognostic index (MZL-IPI) combined these 5 factors, and we defined low (LRG, 0 factors, 27%), intermediate (IRG, 1-2 factors, 57%) and high (HRG, 3+ factors, 16%) risk groups with 5-y PFS of 85%, 66%, and 37%, respectively (c-Harrell = 0.64). Compared to the LRG, the IRG (Hazard Ratio [HR] = 2.30, 95% CI 1.39-3.80) and HRG (HR = 5.41, 95% CI 3.12-9.38) had inferior PFS. Applying the MZL-IPI to the pooled US cohort (N = 353), 94 (27%), 192 (54%), and 67 (19%) patients were classified as LRG, IRG, and HRG, respectively, and the model was validated for PFS (log-rank test p = 0.0018; c-Harrell = 0.578, 95% CI 0.54-0.62). The MZL-IPI was also prognostic for OS in both the training and the external validation sets.

Interpretation

MZL-IPI is a new prognostic score for use in all patients with MZL considered for systemic treatment.

Funding

The MER was supported by P50 CA97274 and U01 CA195568.

Not all central nervous system lymphomas are created equal

Not available.

Loncastuximab tesirine in relapsed/refractory diffuse large B-cell lymphoma: long-term efficacy and safety from the phase II LOTIS-2 study

Therapies that demonstrate durable, long-term responses with manageable safety and tolerability are needed for patients with relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL). Loncastuximab tesirine (loncastuximab tesirine-lpyl [Lonca]), an anti-CD19 antibody conjugated to a potent pyrrolobenzodiazepine dimer, demonstrated single-agent antitumor activity in the pivotal phase II LOTIS-2 study in heavily pretreated patients with R/R DLBCL. Here we present updated efficacy and safety analyses from LOTIS-2, performed for all patients and in subsets of patients with a complete response (CR), including patients with CR who were event-free (no progressive disease or death) for ≥1 year and ≥2 years from cycle 1, day 1 of treatment. Lonca was administered every 3 weeks (0.15 mg/kg for 2 cycles; 0.075 mg/kg for subsequent cycles). As of the final data cutoff (September 15, 2022; median follow-up: 7.8 months [range, 0.3-42.6]), 70 of 145 (48.3%) patients achieved an overall response. Thirty-six (24.8%) patients achieved CR, of which 16 (44%) and 11 (31%) were event-free for ≥1 year and ≥2 years, respectively. In the all-treated population, the median overall survival was 9.5 months; the median progression-free survival was 4.9 months. Among patients with CR, median overall survival and progression-free survival were not reached, with 24-month overall and progression-free survival rates of 68.2% (95% CI: 50.0-81.0) and 72.5% (95% CI: 48.2-86.8), respectively. No new safety concerns were detected. With additional follow-up, Lonca continued to demonstrate durable, long-term responses with manageable safety and tolerability in patients with CR (clinicaltrials gov. Identifier: NCT03589469).

PET/CT Biomarkers Enable Risk Stratification of Patients with Relapsed/Refractory Diffuse Large B-cell Lymphoma Enrolled in the LOTIS-2 Clinical Trial

PURPOSE

Significant progress has occurred in developing quantitative PET/CT biomarkers in diffuse large B-cell lymphoma (DLBCL). Total metabolic tumor volume (MTV) is the most extensively studied, enabling assessment of FDG-avid tumor burden associated with outcomes. However, prior studies evaluated the outcome of cytotoxic chemotherapy or chimeric antigen receptor T-cell therapy without data on recently approved FDA agents. Therefore, we aimed to assess the prognosis of PET/CT biomarkers in patients treated with loncastuximab tesirine.

EXPERIMENTAL DESIGN

We centrally reviewed screening PET/CT scans of patients with relapsed/refractory DLBCL enrolled in the LOTIS-2 (NCT03589469) study. MTV was obtained by computing individual volumes using the SUV ≥4.0 threshold. Other PET/CT metrics, clinical factors, and the International Metabolic Prognostic Index (IMPI) were evaluated. Logistic regression was used to assess the association between biomarkers and treatment response. Cox regression was used to determine the effect of biomarkers on time-to-event outcomes. We estimated biomarker prediction as continuous and binary variables defined by cutoff points.

RESULTS

Across 138 patients included in this study, MTV with a cutoff point of 96 mL was the biomarker associated with the highest predictive performance in univariable and multivariable models to predict failure to achieve complete metabolic response (OR, 5.42; P = 0.002), progression-free survival (HR, 2.68; P = 0.002), and overall survival (HR, 3.09; P < 0.0001). IMPI demonstrated an appropriate performance, however, not better than MTV alone.

CONCLUSIONS

Pretreatment MTV demonstrated robust risk stratification, with those patients demonstrating high MTV achieving lower responses and survival to loncastuximab tesirine in relapsed/refractory DLBCL.

Impact of cumulative dose of brentuximab vedotin on outcomes of frontline therapy for advanced-stage Hodgkin lymphoma

In the pivotal study ECHELON-1, brentuximab vedotin (BV), doxorubicin, vinblastine, and dacarbazine (A + AVD) demonstrated superior efficacy compared with bleomycin + AVD for the treatment of advanced-stage classic Hodgkin lymphoma (cHL). However, there are minimal available data regarding the frequency of dose reductions or omission of BV during curative therapy and the potential impact on patient outcomes. In a real-world analysis, we retrospectively reviewed the characteristics and outcomes of 179 patients with stage III or IV cHL treated with frontline A + AVD from January 2010 to April 2022. Treatment consisted of up to 1.2 mg/kg of BV and standard dose AVD IV on days 1 and 15 of each 28-day cycle for up to 6 cycles. At the time of treatment, the median patient age was 37 years, and a high-risk International Prognostic Score was observed in 46% of patients. Overall, 91% of patients received 6 cycles of AVD; 55% of patients did not receive the intended cumulative dose of BV (CDB); 28% of patients received two-thirds or less than the planned CDB. At a median follow-up time of 27.4 months (95% confidence interval [CI], 24.8-29), the median progression-free survival (PFS) was not reached, and the 12-month PFS was 90.3% (95% CI, 85.9-95.0). The impact of CDB on PFS was not significant (P = .15), nor was high CDB significantly associated with increased adverse events. In real-world experience, A + AVD is a highly effective treatment for patients with advanced-stage cHL, including for patients with prominent dose reductions of BV.

How I treat secondary CNS involvement by aggressive lymphomas

Secondary central nervous system (CNS) lymphoma (SCNSL) is a rare but clinically challenging scenario with historically disappointing outcomes. SCNSL refers to lymphoma that has spread into the CNS concurrently with systemic disease or CNS relapse during or after frontline immunochemotherapy, presenting with or without systemic lymphoma. Diffuse large B-cell lymphoma (DLBCL) denotes the most common entity, but an increased incidence is observed in other histologies, such as Burkitt lymphoma and mantle-cell lymphoma. The incidence, timing in disease course, location, evidence supporting the use of CNS prophylaxis, and treatment pathways vary according to histology. No randomized data exist to delineate the best treatment approaches with current recommendations based on retrospective and single-arm studies. However, a regimen comprising immunochemotherapy, incorporating agents that cross the blood-brain barrier, followed by thiotepa-containing conditioning and autologous stem-cell transplant outlined in the international MARIETTA study demonstrated improvement in outcomes, representing a major accomplishment in the care of patients with DLBCL with SCNSL. Anti-CD19 chimeric antigen receptor T cell denotes a paradigm shift in the treatment of patients with systemic aggressive lymphomas, with emerging data also demonstrating efficacy without higher neurotoxicity in those with SCNSL. In this manuscript we discuss 5 clinical scenarios and review the evidence supporting our recommendations.

Quantitative PET-based biomarkers in lymphoma: getting ready for primetime

The use of functional quantitative biomarkers extracted from routine PET-CT scans to characterize clinical responses in patients with lymphoma is gaining increased attention, and these biomarkers can outperform established clinical risk factors. Total metabolic tumour volume enables individualized estimation of survival outcomes in patients with lymphoma and has shown the potential to predict response to therapy suitable for  risk-adapted treatment approaches in clinical trials. The deployment of machine learning tools in molecular imaging research can assist in recognizing complex patterns and, with image classification, in tumour identification and segmentation of data from PET-CT scans. Initial studies using fully automated approaches to calculate metabolic tumour volume and other PET-based biomarkers have demonstrated appropriate correlation with calculations from experts, warranting further testing in large-scale studies. The extraction of computer-based quantitative tumour characterization through radiomics can provide a comprehensive view of phenotypic heterogeneity that better captures the molecular and functional features of the disease. Additionally, radiomics can be integrated with genomic data to provide more accurate prognostic information. Further improvements in PET-based biomarkers are imminent, although their incorporation into clinical decision-making currently has methodological shortcomings that need to be addressed with confirmatory prospective validation in selected patient populations. In this Review, we discuss the current knowledge, challenges and opportunities in the integration of quantitative PET-based biomarkers in clinical trials and the routine management of patients with lymphoma.

Enhancing prognostication and personalizing treatment of extranodal marginal zone lymphoma

INTRODUCTION

Extranodal marginal zone lymphoma (EMZL) of mucosa-associated lymphoid tissue is an indolent lymphoma originating from marginal zone B-cells and associated with chronic inflammation. EMZL demonstrates distinct genomic alterations according to the primary extranodal site of disease but commonly affects signaling pathways including NF-ĸB, B-cell receptor, and NOTCH. Treatment with radiation therapy is commonly implemented in localized diseases, and multiple agents are available for patients with advanced-stage diseases in need of therapy. Bendamustine with rituximab is a frontline platform associated with high efficacy.

AREAS COVERED

Clinical features, diagnosis, genomics, models enabling risk stratification, treatment options, and future directions.

EXPERT OPINION

The lack of consistent genotyping profile in EMZL precludes the development of tissue and circulatory biomarkers for the diagnosis, risk stratification, and monitoring of minimal residual disease. Furthermore, the biological heterogeneity observed in extranodal sites associated with overall limited genomic data prevents the testing of druggable pathways aiming for a personalized treatment approach. Future clinical trials should focus on EMZL considering the unique clinical characteristics in the eligibility criteria and response assessment to better inform efficacy of novel agents and delineate sequences of therapies.

Outcomes of patients with limited-stage plasmablastic lymphoma: A multi-institutional retrospective study

Plasmablastic lymphoma (PBL) is a rare entity, commonly associated with immunosuppressed states such as human immunodeficiency virus (HIV) infection or solid organ transplant. The clinical course is characterized by high relapse rates and a poor prognosis, leading some clinicians to recommend aggressive frontline therapy. However, a specific review of limited stage (LS) PBL patients is not available to evaluate outcomes and justify treatment recommendations. We performed a retrospective review of LS PBL cases to provide insight into this rare disease. Our cohort consisted of 80 stage I or II PBL patients from 13 US academic centers. With a median follow up of 34 months (1-196), the 3-year progression-free survival (PFS) and overall survival (OS) of the entire cohort were 72% (95% CI 62, 83) and 79% (95% CI 70, 89), respectively. The 3-year PFS and OS of patients treated with frontline chemotherapy alone was 65% (95% CI 50, 84) and 71% (95% CI 56, 89), respectively, compared to 85% (95% CI 72, 100) and 96% (95% CI 89, 100), respectively, in patients treated with combined frontline chemotherapy with radiation consolidation. Our data demonstrate favorable outcomes in LS PBL with no improvements in outcome from aggressive frontline treatment including Hyper-CVAD or auto-SCT consolidation. Multivariate regression analysis (MRA) demonstrated improved PFS for patients receiving EPOCH based frontline therapy versus CHOP (HR: 0.23; p = 0.029). Frontline chemotherapy followed by radiation consolidation versus chemotherapy alone appeared to be associated with improved relapse and survival outcomes but did not show statistical significance in MRA.

Long-term outcomes of patients with conjunctival extranodal marginal zone lymphoma

Comprehensive information on clinical features and long-term outcomes of primary conjunctival extranodal marginal zone lymphoma (PCEMZL) is scarce. We present a large single-institution retrospective study of 72 patients. The median age was 64 years, and 63.9% were female. Stage I was present in 87.5%. Radiation therapy (RT) alone was the most common treatment (70.8%). Complete response (CR) was 87.5%, and 100% in RT-treated patients. With a median follow-up of 6.7 years, relapse/progression and death occurred in 19.4% each, with one relapse within the RT field. The 10-year progression-free survival (PFS) and overall survival (OS) were 68.4% (95% CI 52.8%-79.8%) and 89.4% (95% CI 77.4%-95.2%), respectively. The 10-year rate for time to progression from diagnosis was 22.5% (95% CI 11.6%-35.7%). The 10-year PFS and OS of MALT-IPI 0 versus 1-2 were 83.3% versus 51.3%, (p = .022) and 97.6% versus 76.6%, (p = .0052), respectively. The following characteristics were associated with shorter survival: age > 60 years (PFS: HR = 2.93, 95% CI 1.08-7.95; p = .035, OS: HR = 9.07, 95% CI 1.17-70.26; p = .035) and MALT-IPI 1-2 (PFS: HR = 2.67, 95% CI 1.12-6.31; p = .027, OS: HR = 6.64, 95% CI 1.45-30.37; p = .015). CR following frontline therapy was associated with longer PFS (HR = 0.13, 95% CI 0.04-0.45; p = .001), but not OS. Using the Fine and Gray regression model with death without relapse/progression as a competing risk, RT and CR after frontline therapy were associated with lower risk of relapse (SHR = 0.34, 95% CI 0.12-0.96 p = .041 and SHR = 0.11, 95% CI 0.03-0.36; p < .001, respectively). Patients with PCEMZL treated with frontline RT exhibit excellent long-term survival, and the MALT-IPI score appropriately identifies patients at risk for treatment failure.

Revised MALT-IPI: A new predictive model that identifies high-risk patients with extranodal marginal zone lymphoma

Extranodal marginal zone lymphoma (EMZL) is a heterogeneous disease with a subset of patients exhibiting a more aggressive course. We previously reported that EMZL with multiple mucosal sites (MMS) at diagnosis is characterized by shorter survival. To better recognize patients with different patterns of progression-free survival (PFS) we developed and validated a new prognostic index primarily based on patient's disease characteristics. We derived the "Revised mucosa-associated lymphoid tissue International Prognostic Index" (Revised MALT-IPI) in a large data set (n = 397) by identifying candidate variables that showed highest prognostic association with PFS. The revised MALT-IPI was validated in two independent cohorts, from the University of Iowa/Mayo Clinic (n = 297) and from IELSG-19 study (n = 400). A stepwise Cox regression analysis yielded a model including four independent predictors of shorter PFS. Revised MALT-IPI has scores ranging from 0 to 5, calculated as a sum of one point for each of the following- age >60 years, elevated LDH, and stage III-IV; and two points for MMS. In the training cohort, the Revised MALT-IPI defined four risk groups: low risk (score 0, reference group), low-medium risk (score 1, HR = 1.85, p = .008), medium-high risk (score 2, HR = 3.84, p < .0001), and high risk (score 3+, HR = 8.48, p < .0001). Performance of the Revised MALT-IPI was similar in external validation cohorts. Revised MALT-IPI is a new index centered on disease characteristics that provides robust risk-stratification identifying a group of patients characterized by earlier progression of disease. Revised MALT-IPI can allow a more disease-adjusted management of patients with EMZL in clinical trials and practice.

A roadmap for clinical trial design in marginal zone lymphoma

Marginal zone lymphoma (MZL) is commonly underrepresented in clinical trials collectively studying mostly nodal indolent lymphomas.In this manuscript we propose new inclusion and response criteria defined by MZL subtype and disease location for those with extranodal MZL. Progression of disease within 24 months is associated with poor outcomes in MZL and future studies should assess the efficacy of novel agents in this population.

A Deep Learning-Aided Automated Method for Calculating Metabolic Tumor Volume in Diffuse Large B-Cell Lymphoma

Metabolic tumor volume (MTV) is a robust prognostic biomarker in diffuse large B-cell lymphoma (DLBCL). The available semiautomatic software for calculating MTV requires manual input limiting its routine application in clinical research. Our objective was to develop a fully automated method (AM) for calculating MTV and to validate the method by comparing its results with those from two nuclear medicine (NM) readers. The automated method designed for this study employed a deep convolutional neural network to segment normal physiologic structures from the computed tomography (CT) scans that demonstrate intense avidity on positron emission tomography (PET) scans. The study cohort consisted of 100 patients with newly diagnosed DLBCL who were randomly selected from the Alliance/CALGB 50,303 (NCT00118209) trial. We observed high concordance in MTV calculations between the AM and readers with Pearson's correlation coefficients and interclass correlations comparing reader 1 to AM of 0.9814 (p < 0.0001) and 0.98 (p < 0.001; 95%CI = 0.96 to 0.99), respectively; and comparing reader 2 to AM of 0.9818 (p < 0.0001) and 0.98 (p < 0.0001; 95%CI = 0.96 to 0.99), respectively. The Bland-Altman plots showed only relatively small systematic errors between the proposed method and readers for both MTV and maximum standardized uptake value (SUVmax). This approach may possess the potential to integrate PET-based biomarkers in clinical trials.

Predictive factors and outcomes for ibrutinib in relapsed/refractory marginal zone lymphoma: a multicenter cohort study

Ibrutinib is effective in the treatment of relapsed/refractory (R/R) marginal zone lymphoma (MZL) with an overall response rate (ORR) of 48%. However, factors associated with response (or lack thereof) to ibrutinib in R/R MZL in clinical practice are largely unknown. To answer this question, we performed a multicenter (25 US centers) cohort study and divided the study population into three groups: "ibrutinib responders"-patients who achieved complete or partial response (CR/PR) to ibrutinib; "stable disease (SD)"; and "primary progressors (PP)"-patients with progression of disease as their best response to ibrutinib. One hundred and nineteen patients met the eligibility criteria with 58%/17% ORR/CR, 29% with SD, and 13% with PP. The median PFS and OS were 29 and 71.4 months, respectively, with no difference in PFS or OS based on the ibrutinib line of therapy or type of therapy before ibrutinib. Patients with complex cytogenetics had an inferior PFS (HR = 3.08, 95% CI 1.23-7.67, p = 0.02), while those with both complex cytogenetics (HR = 3.00, 95% CI 1.03-8.68, p = 0.04) and PP (HR = 13.94, 95% CI 5.17-37.62, p < 0.001) had inferior OS. Only primary refractory disease to first-line therapy predicted a higher probability of PP to ibrutinib (RR = 3.77, 95% CI 1.15-12.33, p = 0.03). In this largest study to date evaluating outcomes of R/R MZL treated with ibrutinib, we show that patients with primary refractory disease and those with PP on ibrutinib are very high-risk subsets and need to be prioritized for experimental therapies.

An international analysis evaluating frontline bendamustine with rituximab in extranodal marginal zone lymphoma

Extranodal marginal zone lymphoma (EMZL) is a heterogeneous non-Hodgkin lymphoma. No consensus exists regarding the standard-of-care in patients with advanced-stage disease. Current recommendations are largely adapted from follicular lymphoma, for which bendamustine with rituximab (BR) is an established approach. We analyzed the safety and efficacy of frontline BR in EMZL using a large international consortium. We included 237 patients with a median age of 63 years (range, 21-85). Most patients presented with Eastern Cooperative Oncology Group (ECOG) performance status 0 to 1 (n = 228; 96.2%), stage III/IV (n = 179; 75.5%), and intermediate (49.8%) or high (33.3%) Mucosa Associated Lymphoid Tissue International Prognosis Index (MALT-IPI). Patients received a median of 6 (range, 1-8) cycles of BR, and 20.3% (n = 48) received rituximab maintenance. Thirteen percent experienced infectious complications during BR therapy; herpes zoster (4%) was the most common. Overall response rate was 93.2% with 81% complete responses. Estimated 5-year progression-free survival (PFS) and overall survival (OS) were 80.5% (95% CI, 73.1% to 86%) and 89.6% (95% CI, 83.1% to 93.6%), respectively. MALT-IPI failed to predict outcomes. In the multivariable model, the presence of B symptoms was associated with shorter PFS. Rituximab maintenance was associated with longer PFS (hazard ratio = 0.16; 95% CI, 0.04-0.71; P = .016) but did not impact OS. BR is a highly effective upfront regimen in EMZL, providing durable remissions and overcoming known adverse prognosis factors. This regimen is associated with occurrence of herpes zoster; thus, prophylactic treatment may be considered.

Efficacy and Safety Exposure-Response Analysis of Loncastuximab Tesirine in Patients with B cell non-Hodgkin Lymphoma

We developed an integrated population pharmacokinetic model to investigate loncastuximab tesirine pharmacokinetics (PK) and exposure-response relationships for relapsed/refractory B cell non-Hodgkin lymphoma, including diffuse large B cell lymphoma (DLBCL). The model, based on the recommended dosing schedule (150 µg/kg every 3 weeks [Q3W] for 2 cycles; 75 µg/kg Q3W thereafter) and drug concentrations in phase 1 and 2 studies (DLBCL [n = 284], non-DLBCL [n = 44]), was used to characterize loncastuximab tesirine PK and evaluate exposure covariates. Relationships between exposure (pyrrolobenzodiazepine-conjugated antibody [cAb] cycle 1 average concentration) and (1) efficacy (including overall response rate [ORR; primary endpoint] and overall survival [OS]) and (2) grade ≥ 2 treatment-emergent adverse events were explored. Statistical analyses included univariate and multivariate logistic regression, Kaplan-Meier analysis, and Cox proportional hazard regression. cAb and total Ab were best described by a two-compartment linear model with time-dependent clearance. The cAb steady-state half-life increased to 20.6 days by ~ 15 weeks. cAb exposure was lower for low albumin, mild/moderate hepatic impairment, non-DLBCL subtypes, and Eastern Cooperative Oncology Group scores > 1. Significant positive associations were reported between exposure and ORR (p = 3.21E-6), OS (p = 0.0016), grade ≥ 2 increased gamma-glutamyltransferase, liver function test abnormalities, pain, and skin/nail reactions (p < 0.05). Low albumin, bulky disease, and mild/moderate hepatic impairment had a significant negative effect on OS (p < 0.01). Modeling supports the recommended loncastuximab tesirine dosing schedule. Although reduced exposure and efficacy were predicted for specific covariates (e.g., low albumin, mild/moderate hepatic impairment), dose increases are not recommended. Trial registration: NCT02669017 and NCT03589469.

A single-center analysis of patients with extranodal marginal zone lymphoma of the breast

Breast extranodal marginal zone lymphoma (EMZL) is a rare malignancy. We performed the largest published to date single-center retrospective analysis of 13 patients with breast EMZL focusing on clinical characteristics and treatment-related outcomes. The rarity of this disease at our center was concordant with the prevalence reported in the literature, with breast EMZL comprising 2% of 654 MZL cases. Most patients presented with stage I-II disease however four (30.8%) patients had stage IV disease mostly due to occult bone marrow (BM) involvement. Interestingly, EMZL was frequently non-FDG avid (66.7%) on staging PET/CT. With a median follow-up of 3.1 years (range 5 months to 10.2 years), the 3-year progression free survival was 68.7% (95%CI 30.2%-88.9%) and overall survival 80.2% (95%CI 40.3%-94.8%). No patient experienced higher-grade transformation. Herein we show that localized breast EMZL can be effectively treated with radiation therapy providing long term disease control.

NOTCH signaling in the pathogenesis of splenic marginal zone lymphoma-opportunities for therapy

NOTCH signaling is a highly conserved pathway mediated by four receptors (NOTCH 1-4) playing critical functions in proliferation, differentiation, and cell death. Under physiologic circumstances, NOTCH2 is a key regulator in marginal zone differentiation and development. Over the last decade, growing data demonstrated frequent NOTCH2 mutations in splenic marginal zone lymphoma (SMZL) underscoring its critical role in the pathogenesis of this disease. Moreover, NOTCH2 specificity across studies supports the rationale to assess its value as a diagnosis biomarker in a disease without pathognomonic features. These data make NOTCH signaling an appealing target for drug discovery in SMZL; however, prior efforts attempting to manipulate this pathway failed to demonstrate meaningful clinical benefit, or their safety profile prevented further development. In this review, we discuss the current knowledge of NOTCH implications in the pathogenesis and as a potential druggable target in SMZL.

Mantle cell lymphoma involving the thyroid gland

Mantle cell lymphoma (MCL) rarely involves thyroid gland. Positron emission tomography-computed tomography (PET-CT) may be critical in identifying thyroid involvement by MCL and pursuing further work up of the suspicious thyroid lesions, irrespective of the thyroid function tests.

Prognostic value of presalvage metabolic tumor volume in patients with relapsed/refractory diffuse large B-cell lymphoma

Identification of new prognostic factors in relapsed/refractory (rel/ref) diffuse large B-cell lymphoma (DLBCL) is essential for developing risk-adapted approaches. We retrospectively analyzed prognostication based on metabolic tumor volume (MTV) in rel/ref DLBCL (n = 108) before platinum-based salvage chemotherapy. Using 41% SUVmax threshold, patients achieving complete response (CR) exhibited significantly lower baseline values of MTV, compared to those achieving partial response (PR) or with progression of disease (medians MTV 16.26 versus 72.51 versus 98.11 ml, respectively). As a continuous variable, log₂(MTV) was predictive of failure to achieve CR (1-unit increase odds ratio [OR] = 1.58, p < 0.001). Log₂(MTV) significantly predicted progression-free survival (PFS) and overall survival (OS), and one-unit increase in log₂(MTV) was associated with shorter PFS (hazard ratio [HR] = 1.12, p = 0.035) and OS (HR = 1.17, p = 0.007). However, heterogeneity in the selection of post-salvage chemotherapy approaches may have affected survival. These data demonstrate the ability of presalvage MTV to discriminate responders from non-responders to platinum-based chemotherapy and predict survival.

EBV-positive HIV-associated diffuse large B cell lymphomas are characterized by JAK/STAT (STAT3) pathway mutations and unique clinicopathologic features

Even in the era of highly active combination antiretroviral therapy (cART), patients with HIV have a disproportionate risk of developing aggressive lymphomas that are frequently Epstein-Barr virus (EBV)-related. Here, we investigate HIV-associated diffuse large B-cell lymphoma (HIV-DLBCL) and compare EBV-positive and EBV-negative cases. HIV-DLBCL were identified from two academic medical centres and characterised by immunohistochemistry, EBV status, fluorescence in situ hybridisation, cell of origin determination by gene expression profiling, and targeted deep sequencing using a custom mutation panel of 334 genes. We also applied the Lymphgen tool to determine the genetic subtype of each case. Thirty HIV-DLBCL were identified, with a median patient age of 46 years and male predominance (5:1). Thirteen cases (48%) were EBV-positive and 14 (52%) EBV-negative. Nine of the 16 tested cases (56%) had MYC rearrangement, three (19%) had BCL6 (two of which were double hit MYC/BCL6) and none had BCL2 rearrangements. Using the Lymphgen tool, half of the cases (15) were classified as other. All HIV-DLBCL showed mutational abnormalities, the most frequent being TP53 (37%), MYC (30%), STAT3 (27%), HIST1H1E (23%), EP300 (20%), TET2 (20%), SOCS1 (17%) and SGK1 (17%). EBV-negative cases were mostly of germinal centre B-cell (GCB) origin (62%), showed more frequent mutations per case (a median of 13·5/case) and significant enrichment of TP53 (57% vs. 15%; P = 0·046), SGK1 (36% vs. 0%; P = 0·04), EP300 (43% vs. 0%; P = 0·02) and histone-modifying gene (e.g. HIST1H1E, HIST1H1D, 79% vs. 31%; P = 0·02) mutations. EBV-positive cases were mostly of non-GCB origin (70%), with fewer mutations per case (median 8/case; P = 0·007), and these tumours were enriched for STAT3 mutations (P = 0·10). EBV-positive cases had a higher frequency of MYC mutations but the difference was not significant (36% vs. 15%; P = 0·38). EBV-association was more frequent in HIV-DLBCLs, arising in patients with lower CD4 counts at diagnosis (median 46·5 vs. 101, P = 0·018). In the era of cART, approximately half of HIV-DLBCL are EBV-related. HIV-DLBCL are enriched for MYC rearrangements, MYC mutations and generally lack BCL2 rearrangements, regardless of EBV status. Among HIV-DLBCL, tumours that are EBV-negative and EBV-positive appear to have important differences, the latter arising in context of lower CD4 count, showing frequent non-GCB origin, lower mutation burden and recurrent STAT3 mutations.

Abstract 1366: Integrated population modeling of loncastuximab tesirine (Lonca) exposure in B-cell non-Hodgkin lymphoma (B-NHL)

Lonca is an antibody (Ab) drug conjugate comprising a humanized monoclonal Ab directed against B-cell antigen CD19, conjugated with a potent pyrrolobenzodiazepine (PBD) dimer toxin. In a Phase 1 (NCT02669017) study in relapsed or refractory (R/R) B-NHL, a recommended Phase 2 dosing regimen for Lonca of 150 µg/kg once every 3 weeks (Q3W) for two doses, followed by 75 µg/kg Q3W was identified then evaluated in a Phase 2 (NCT03589469) study in R/R diffuse large B-cell lymphoma (DLBCL). A population pharmacokinetic (PPK) model was developed to characterize the pharmacokinetics (PK) of the Lonca dosing regimen and evaluate exposure covariates.

The integrated PPK model was used to describe drug concentrations for Lonca PBD-conjugated Ab (5,301 samples), total Ab (5,241 samples), and unconjugated warhead SG3199 (239 samples) in serum from 328 patients. Samples were taken pre-dose, at end of infusion and at pre-determined timepoints post-infusion throughout the trials. Analysis was performed using non-linear mixed-effects modeling (NONMEM, v7.4 [ICON Solutions]). Subgroup analyses were conducted on model-predicted exposure metrics derived from simulation of Lonca PK profiles based on empirical Bayesian estimates of individual PK parameters.

Concentration-time data of Lonca PBD-conjugated Ab and total Ab were best characterized by a two-compartment model with parallel linear clearance (0.218 L/day), and a time-dependent clearance component which approached zero by ~15 weeks. The estimated volume of distribution of central compartment was 3.86 L and the estimated typical half-life at steady state of Lonca is ~3 weeks. The effect of body weight, age, sex, race, renal impairment, drug formulation, anti-drug Ab, ECOG, and concomitant P-gp inhibitors did not show clinically important influence on exposure (&lt; ±30% change relative to reference). Based on model-predicted Cycle 1 average concentration (Cavg) patients with low albumin (&lt;35 g/L, n=49) had 52% lower Cavg than patients with normal albumin levels (≥35 g/L, n=279). Patients with non-DLBCL (n=44) had 61% lower Cavg than patients with DLBCL (n=284). Trends of lower exposures with baseline mild/moderate hepatic impairment and ECOG status &gt;1 were noted but did not appear to be of clinical relevance.

In conclusion, Lonca exposure was well described by a two-compartment model with linear and time-dependent clearance; the latter is thought to reflect reduction of tumor cells. Lonca exposure was lower in non-DLBCL patients, and lower in patients with hypoalbuminemia secondary to enhanced protein clearance in patients with critical illness. Overall, modeling demonstrates rapid attainment of steady-state exposure for Lonca given 150 µg/kg Q3W for two doses, and a sustaining profile for Lonca given 75 µg/kg Q3W thereafter for patients with DLBCL.

Citation Format: Melhem Solh, Juan Pablo Alderuccio, Anastasios Stathis, David Ungar, Sam Liao, Lisa Khouri, Xiaoyan Zhang, Joseph Boni. Integrated population modeling of loncastuximab tesirine (Lonca) exposure in B-cell non-Hodgkin lymphoma (B-NHL) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1366.

Duration of response to loncastuximab tesirine in relapsed/refractory diffuse large B-cell lymphoma by demographic and clinical characteristics: Subgroup analyses from LOTIS 2

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Background: Outcomes for patients with refractory/relapsed diffuse large B-cell lymphoma (R/R DLBCL) are poor, particularly for those with high-risk clinical characteristics. There remains an unmet need for new treatment options for these patients. Loncastuximab tesirine (Lonca) is an antibody-drug conjugate comprising a humanized anti-CD19 antibody conjugated to a potent pyrrolobenzodiazepine dimer toxin. LOTIS 2 was a pivotal Phase 2 study that demonstrated substantial single-agent anti-cancer activity of Lonca in patients with R/R DLBCL. Efficacy and safety data were presented at ASH 2020 (Caimi et al, ASH 2020; abstract 1183). Here we present subgroup analyses of duration of response (DoR) to Lonca by demographic and clinical characteristics. Methods: Adult patients with R/R DLBCL who had received ≥2 prior therapies were enrolled in this Phase 2, multicenter, single-arm, open-label study of single-agent Lonca (150 µg/kg every 3 weeks for 2 doses, followed by 75 µg/kg thereafter for up to 1 year). The primary analysis has previously been reported, with a primary endpoint of overall response rate (ORR). Patients are being followed-up every 12 weeks for up to 3 years. DoR was a key secondary efficacy endpoint, defined as time from the first documentation of response (central review) to disease progression or death. We analyzed pre-specified demographic and clinical characteristic subgroups for DoR. Results: As of data cut-off (August 6, 2020), ORR in the total population (N = 145) was 48.3% (24.8% had complete response [CR] and 23.4% had partial response [PR]). Median DoR (mDoR) for the 70 responders was 12.58 months. mDoR for patients with CR and PR was 13.37 months and 5.68 months, respectively. Overall, subgroups with high-risk characteristics for poor prognosis had a DoR comparable to the whole study population. mDoR for patients with double-/triple-hit DLBCL was 13.37 months, with advanced stage disease was 12.58 months, and with transformed disease was 12.58 months. The mDoR for older patients was longer than for younger patients (≥75 years, 13.37 months; 65 to < 75 years, 12.58 months; < 65 years, 9.26 months). Patients with DLBCL refractory (defined as no response to therapy) to first-line, most recent line, and all prior lines of therapy had mDoRs of 9.63 months, 9.26 months, and 9.63 months, respectively. Conclusions: Durable responses were observed with the recommended Phase 2 dose regimen of Lonca in heavily pre-treated patients and those at high risk of poor prognosis, including older patients and those with double-/triple-hit, advanced stage, transformed, and primary refractory DLBCL. Updated DoR data will be presented at the meeting. Clinical trial information: NCT03589469.

Burkitt lymphoma in the modern era: real-world outcomes and prognostication across 30 US cancer centers

We examined adults with untreated Burkitt lymphoma (BL) from 2009 to 2018 across 30 US cancer centers. Factors associated with progression-free survival (PFS) and overall survival (OS) were evaluated in univariate and multivariate Cox models. Among 641 BL patients, baseline features included the following: median age, 47 years; HIV+, 22%; Eastern Cooperative Oncology Group (ECOG) performance status (PS) 2 to 4, 23%; >1 extranodal site, 43%; advanced stage, 78%; and central nervous system (CNS) involvement, 19%. Treatment-related mortality was 10%, with most common causes being sepsis, gastrointestinal bleed/perforation, and respiratory failure. With 45-month median follow-up, 3-year PFS and OS rates were 64% and 70%, respectively, without differences by HIV status. Survival was better for patients who received rituximab vs not (3-year PFS, 67% vs 38%; OS, 72% vs 44%; P < .001) and without difference based on setting of administration (ie, inpatient vs outpatient). Outcomes were also improved at an academic vs community cancer center (3-year PFS, 67% vs 46%, P = .006; OS, 72% vs 53%, P = .01). In multivariate models, age ≥ 40 years (PFS, hazard ratio [HR] = 1.70, P = .001; OS, HR = 2.09, P < .001), ECOG PS 2 to 4 (PFS, HR = 1.60, P < .001; OS, HR = 1.74, P = .003), lactate dehydrogenase > 3× normal (PFS, HR = 1.83, P < .001; OS, HR = 1.63, P = .009), and CNS involvement (PFS, HR = 1.52, P = .017; OS, HR = 1.67, P = .014) predicted inferior survival. Furthermore, survival varied based on number of factors present (0, 1, 2 to 4 factors) yielding 3-year PFS rates of 91%, 73%, and 50%, respectively; and 3-year OS rates of 95%, 77%, and 56%, respectively. Collectively, outcomes for adult BL in this real-world analysis appeared more modest compared with results of clinical trials and smaller series. In addition, clinical prognostic factors at diagnosis identified patients with divergent survival rates.

Expression of germinal center cell markers by extranodal marginal zone lymphomas of MALT type within colonized follicles, a diagnostic pitfall with follicular lymphoma

We reviewed 341 consecutive cases of marginal zone lymphoma (MZL) (47) or follicular lymphoma (FL) (294) of which 7 were difficult to distinguish due to perceived coexpression of BCL6 and BCL2 by tumor cells in follicular foci. This stimulated us to develop dual BCL6/BCL2 immunohistochemistry, allowing us to assess coexpression among individual cells. Dual staining confirmed coexpression in 6 of 7 cases, all extranodal MZL (ENMZL) based on overall features and representing 13% of MZL in this series. These findings confirm that MZL cells have plasticity regarding protein expression within the germinal center (GC) microenvironment, an important diagnostic pitfall. Intriguingly, in all MZL expressing BCL6, non-neoplastic GC B cells within colonized follicles showed diminished or absent CD10 expression but preserved BCL6 and high ki67. This finding suggests plasticity of CD10 expression in non-neoplastic GC B cells in the context of colonization by MZL, possibly related to NF-kB dysregulation.

Clinical and radiological characteristics of patients with pulmonary marginal zone lymphoma: A single center analysis

Pulmonary marginal zone lymphoma (PMZL) is the most common non‐Hodgkin lymphoma affecting the lung. PMZL is usually an indolent disease. Clinical and radiological variables associated with shorter survival are largely unknown and no consensus exists on preferred treatment strategy in PMZL. Herein we aimed to identify clinical and radiological features associated with shorter survival and inferior treatment outcomes. Forty patients with PMZL were analyzed. FDG‐avid disease was evident in most patients (93%) with staging PET/CT (n = 15). With a median follow‐up in treated patients (n = 38) of 8.4 years (range 0.07‐18.44), the median progression‐free survival (PFS) and overall survival (OS) were 7.5 years (95% CI 1.8‐9.5) and 15.7 years (95% CI 9.3‐NE) respectively. Shorter PFS was observed in patients who presented at diagnosis with elevated LDH, B symptoms, advanced stage and failed to achieve complete response (CR) after initial treatment. Patients with multifocal lung disease, extrapulmonary MZL and cavitary lesions on CT scans exhibited shorter PFS. Nevertheless, no clinical or radiologic findings were associated with shorter OS. All patients treated with surgery (n = 4) and radiation therapy (n = 3) achieved and remained in CR. No higher grade transformations occurred during the follow‐up period. PMZL exhibited excellent outcomes with a 15‐year PMZL‐related OS of 94.9% (95% CI: 81.25%‐98.7%). Radiation therapy and surgery are potentially curative strategies in localized PMZL.

Central nervous system emergencies in haematological malignancies

Neurological emergencies are frequently catastrophic events in the course of haematological malignancies (HM) that, if not promptly recognized and treated, may lead to lethal outcomes or chronic sequelae. They may occur at any time during the disease course, but are more frequently observed following relapse. Practice guidelines are lacking in the management of most central nervous system (CNS) complications in HM. Herein we review the pathophysiology, presentation and treatment of elevated intracranial pressure, spinal cord compression, status epilepticus, neurovascular complications, CNS infection, leucostasis and hyperviscosity. Further, we discuss the expanding spectrum of neurological complications of old and novel treatments in HM.

Short survival and frequent transformation in extranodal marginal zone lymphoma with multiple mucosal sites presentation

Between 11 and 37% of extranodal marginal zone lymphoma (EMZL) patients present with disease involvement in multiple mucosal sites (MMS). We analyzed 405 EMZL patients seen between 1995 and 2017: 265 (65.4%) patients presented with stage I disease, 49 of 309 (15.8%) patients with bone marrow involvement, and 35 of 328 (10.7%) patients with monoclonal gammopathy (MG). Forty-three (10.6%) patients had MMS presentation, which was more frequently seen in patients aged >60 years (55.8%). Five (17.9%) of 28 MMS patients had MG. MMS patients commonly exhibited the International Prognostic Index (IPI) >2 (79.1%), Follicular Lymphoma International Prognostic Index (FLIPI) >2 (39.5%), and Mucosa-Associated Lymphoid Tissue Lymphoma International Prognostic Index (MALT-IPI) 2-3 (60.5%). Both MMS presentation and MG were associated with shorter survival univariately. In multivariable Cox regression models, shorter progression-free survival (PFS) and overall survival (OS) were observed in patients with MMS (hazard ratio [HR] = 3.08 and 2.92, respectively), age ≥60 years (HR = 1.52 and 2.45, respectively), and in patients who failed to attain a complete remission following initial therapy (HR = 3.27 and 2.13, respectively). Elevated lactate dehydrogenase was associated with shorter PFS (HR = 1.92), while anemia (HR = 2.46) was associated with shortened OS. MALT-IPI ≥2 (HR = 2.47 and 4.75), FLIPI >2 (HR = 1.65 and 2.09), and IPI >2 (HR = 2.09 and 1.73) were associated with shorter PFS and OS, respectively. Higher grade transformation (HGT) occurred in 11 (25.6%) MMS patients with a 5-year cumulative incidence of 13.2% (95% CI 4.7-26.1%). EMZL patients with MMS presentation represent a novel clinical subset associated with shorter PFS, OS, and higher incidence of HGT that needs novel therapeutic approaches.

Bilateral radiation therapy followed by methotrexate-based chemotherapy for primary vitreoretinal lymphoma

Primary vitreoretinal lymphoma (PVRL) is a subset of primary CNS lymphoma that presents as isolated ocular disease without brain involvement. Although ocular radiotherapy (RT) is an effective treatment for PVRL, the optimal treatment is uncertain. PVRL may later involve the brain in 56%-85% of patients. We report on 12 PVRL patients treated with a combination of bilateral RT and a systemic chemotherapy (CT) regimen containing high-dose methotrexate (M). Ten received RT (30-40 Gy) followed by CT, one received RT, and one was treated with intravitreal M; all achieved a complete response (CR). Three patients had tumor recurrence in the brain and received CT and one patient relapsed in the eye with a second recurrence in the brain. Three patients achieved CR-2 remain alive and one died of dementia. One died from recurrent CNS disease. With a median follow of 68 months (range, 17-154 months), median progression-free and overall survival have not been reached. Bilateral RT followed by M-based CT is an effective treatment for reducing CNS progression and prolonging survival.

Maintenance rituximab or observation after frontline treatment with bendamustine-rituximab for follicular lymphoma

Bendamustine (B) with rituximab (R) is a standard frontline treatment for medically fit follicular lymphoma (FL) patients. The safety and efficacy of maintenance rituximab (MR) after BR induction has not been formally compared to observation for FL, resulting in disparate practice patterns. Prospective trials have shown benefit of MR after R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) or R-CVP (rituximab, cyclophosphamide, vincristine, prednisone), yet recent data from the GALLIUM study comparing outcomes of patients treated with chemotherapy with R or obinutuzumab (G) showed higher than anticipated fatal adverse events with BR/BG. In order to assess the efficacy and tolerability of MR after BR, we retrospectively collected data on 640 newly diagnosed patients treated with FL. We found that patients who achieved partial remission (PR) after ≥4 cycles of BR had improved duration of response (DOR) with MR vs. no maintenance, whereas those in complete remission did not. These findings were confirmed in a validation cohort. In the entire study population, the known fatal adverse event rate after BR was 2·5% and did not significantly differ in those receiving MR versus no maintenance. [Correction added on 14 January 2019, after online publication: The preceding sentence has been corrected in this current version.] Within the limitations inherent to retrospective analysis, these data suggest that FL patients with a PR to BR experience prolongation of remission with MR with an acceptable safety profile.

Risk Factors for Transformation to Higher-Grade Lymphoma and Its Impact on Survival in a Large Cohort of Patients With Marginal Zone Lymphoma From a Single Institution

PURPOSE

Given the paucity of data on higher-grade transformation (HGT) to aggressive lymphoma in patients with marginal zone lymphoma (MZL), we report on a large cohort of patients, identify risk factors, and determine HGT impact on overall survival (OS).

METHODS

We analyzed 453 patients with biopsy-proven MZL seen at our institution between 1995 and 2016. Kaplan-Meier, Cox proportional hazards regression, and competing risk methods were used in analyses of time-to-event outcomes.

RESULTS

Thirty-four patients (7.5%) had biopsy-proven HGT to diffuse large B-cell lymphoma, including seven (21%) diagnosed at the time of initial MZL diagnosis. Among 27 incident patients, median time to HGT was 29 months (range, 1.3 to 135 months). Higher risk of HGT was observed in those with nodal/splenic MZL (subdistribution hazard ratio [SHR], 2.60; P = .023). On multivariable competing risk analysis, elevated lactate dehydrogenase (SHR, 2.71), more than four nodal sites (SHR, 2.97), and failure to achieve complete remission (CR) after initial treatment (SHR, 3.76) conveyed significantly higher risk for HGT ( P < .02). International Prognostic Index (IPI), Follicular Lymphoma IPI, and Mucosa-Associated Lymphoid Tissue Lymphoma IPI were only significant predictors of HGT univariably. Patients with HGT had shorter OS (5-year rate, 65% v 86%; P < .001). Patients who presented with HGT within 12 months since MZL diagnosis had shorter OS than those with HGT at MZL diagnosis combined with those with HGT more than 12 months later (4-year rate, 43% v 81%, P < .001). Non-CR and higher scores of IPI, Follicular Lymphoma IPI, and Mucosa-Associated Lymphoid Tissue Lymphoma IPI were the main significant predictors for shorter progression-free survival and OS.

CONCLUSION

Failure to achieve CR after initial treatment, elevated lactate dehydrogenase, and more than four nodal sites at the time of MZL diagnosis are the main predictors of increased risk of HGT. Patients with HGT have shorter OS.

Smoothened stabilizes and protects TRAF6 from degradation: A novel non-canonical role of smoothened with implications in lymphoma biology

Tumor necrosis factor receptor-associated factor 6 (TRAF6), an (K63) E3-ligase, plays a role in many biological processes and its activity is relevant in diffuse large B cell lymphoma (DLBCL) biology. Although molecules that trigger TRAF6 activation have been defined, those that stabilize TRAF6 and/or enhance TRAF6 function remain largely unclear. We found that TRAF6 amplifies pAKT signaling in DLBCL. Moreover, TRAF6 activation and stabilization of its ubiquitination profile are facilitated by smoothened (SMO), signal transducer of canonical Hedgehog signaling. Here, we report that SMO is needed to facilitate and maintain TRAF6-dependent elevated pAKT levels, and that the SMO/TRAF6 axis contributes to doxorubicin resistance in DLBCL. Mechanistically, we found that SMO, through its C-terminal tail, stabilizes and protects TRAF6 from degradation, an effect mediated by ubiquitin-specific protease-8. Moreover, this functional link between SMO and TRAF6 is reflected in DLBCL patients where high expression of both molecules correlates with poor prognosis. In summary, our study reveals a novel cell survival mechanism in which SMO stabilizes and protects TRAF6 from degradation. The axis SMO/TRAF6/AKT is highly relevant in the biology of DLBCL and is involved in doxorubicin resistance.

Frontline brentuximab vedotin in breast implant-associated anaplastic large-cell lymphoma

We report a woman who developed BIA-ALCL 9 years after saline implant placement. The lymphoma manifested as a mass lesion associated with axillary lymphadenopathy. She was successfully treated with brentuximab vedotin with minimal toxicity. Brentuximab vedotin may be a promising frontline therapeutic modality for patients with BIA-ALCL.

Decreased survival in hepatitis C patients with monomorphic post-transplant lymphoproliferative disorder after liver transplantation treated with frontline immunochemotherapy

Post-transplant lymphoproliferative disorder (PTLD) develops in 1-3% of liver transplant recipients and no consensus exists about therapeutic management. From 2006 to 2016, 1489 liver transplants were performed at our institution with 20 patients (incidence 1.3%) developing PTLD. Hepatitis C virus (HCV) was the leading cause (n = 10) of liver transplant in PTLD patients. Diffuse large B-cell lymphoma was the most frequent histologic subtype (n = 17), and we report our experience in the management of these patients. Patients were treated with frontline immunochemotherapy without immunosuppression reduction. All evaluable patients achieved a complete remission. Statistically significant decreased survival was identified in HCV-positive patients. Six patients (60%) exhibited increases in HCV RNA levels during therapy. Four patients (40%) developed graft failure and three of them (30%) died from liver dysfunction. This is the first study providing evidence of decreased survival in HCV-positive PTLD patients after liver transplant receiving immunochemotherapy.