Primary central nervous system lymphomas in immunocompromised patients require specific response criteria.

PURPOSE: Immunosuppression is a well-established risk factor for primary central nervous system lymphomas (PCNSLs), which present in this context distinct radiological characteristics. Our aim was to describe the radiological evolution of treated PCNSL in immunocompromised patients and suggest adapted MRI response criteria. METHODS: We conducted a multicenter retrospective study of patients from the French LOC, K-Virogref and CANCERVIH network databases and enrolled adult immunocompromised patients with newly diagnosed PCNSL. RESULTS: We evaluated the baseline, intermediate, end-of-treatment and follow-up MRI data of 31 patients (9 living with HIV, 16 with solid organ transplantation and 6 with an autoimmune disease under chronic immunosuppressive therapy). At baseline, 23/30 (77%) patients had necrotic lesions with ring enhancement and 28% of the lesions were hemorrhagic. At the end of the first-line treatment, 12/28 (43%) patients could not be classified according to the IPCG criteria. Thirteen of 28 (46%) patients still harbored contrast enhancement, and 11/28 (39%) patients had persistent large necrotic lesions with a median diameter of 15 mm. These aspects were not associated with a pejorative outcome and progressively diminished during follow-up. Six patients relapsed; however, we failed to identify any neuroimaging risk factors on the end-of-treatment MRI. CONCLUSION: In immunocompromised patients, PCNSLs often harbor alarming features on end-of-treatment MRI, with persistent contrast-enhanced lesions frequently observed. However, these aspects seemed to be related to the necrotic and hemorrhagic nature of the lesions and were not predictive of a pejorative outcome. Specific response criteria for this population are thereby proposed.

CAR T-cell therapy induces a high rate of prolonged remission in relapsed primary CNS lymphoma: Real-life results of the LOC network.

The prognosis of relapsed primary central nervous system lymphoma (PCNSL) remains dismal. CAR T-cells are a major contributor to systemic lymphomas, but their use in PCNSL is limited. From the LOC network database, we retrospectively selected PCNSL who had leukapheresis for CAR-T cells from the third line of treatment, and, as controls, PCNSL treated with any treatment, at least in the third line and considered not eligible for ASCT. Twenty-seven patients (median age: 68, median of three previous lines, including ASCT in 14/27) had leukapheresis, of whom 25 received CAR T-cells (tisa-cel: N = 16, axi-cel: N = 9) between 2020 and 2023. All but one received a bridging therapy. The median follow-up after leukapheresis was 20.8 months. The best response after CAR-T cells was complete response in 16 patients (64%). One-year progression-free survival from leukapheresis was 43% with a plateau afterward. One-year relapse-free survival was 79% for patients in complete or partial response at CAR T-cell infusion. The median overall survival was 21.2 months. Twenty-three patients experienced a cytokine release syndrome and 17/25 patients (68%) a neurotoxicity (five grade ≥3). The efficacy endpoints were significantly better in the CAR T-cell group than in the control group (N = 247) (median PFS: 3 months; median OS: 4.7 months; p < 0.001). This series represents the largest cohort of PCNSL treated with CAR T-cells reported worldwide. CAR T-cells are effective in relapsed PCNSL, with a high rate of long-term remission and a reassuring tolerance profile. The results seem clearly superior to those usually observed in this setting.

Failure of bamlanivimab with selection of E484K mutation in an allogeneic stem cell transplant recipient with nosocomial SARS-CoV-2 infection.

We report the case of an allogeneic stem cell transplant recipient with nosocomial acquisition of SARS-CoV-2 infection who received antispike neutralizing monoclonal antibody bamlanivimab 2 days after diagnosis of SARS-CoV-2 infection but progressed to severe COVID-19 pneumonia and died with the selection of E484K/Q resistance mutations to bamlanivimab.

Prognostic Value of CSF IL-10 at Early Assessment of Induction Chemotherapy in Primary CNS Lymphomas: A LOC Network Study.

OBJECTIVES: Despite a high response rate at the first evaluation during induction chemotherapy, the risk of early relapse remains high and unpredictable in primary CNS lymphomas (PCSNLs). We aimed to assess the prognostic value of early IL-10 levels in CSF (e-IL-10) after 2 months of induction chemotherapy. METHODS: We retrospectively selected from the LOC (Lymphomes Oculo-Cérébraux) network database patients with PCSNLs who had complete or partial response at the 2-month evaluation of a high-dose methotrexate-based first-line chemotherapy for whom e-IL-10 was available. RESULTS: Thirty patients (median age: 62 years, brain involvement in 30/30, CSF involvement in 10/30, median baseline CSF IL-10: 27.5 pg/mL) met the selection criteria. e-IL-10 was undetectable in 22 patients and detectable in 8 patients. At the end of induction treatment, 7 of 8 and 4 of 22 of the patients with detectable and undetectable e-IL-10 had experienced progressive disease, respectively (p = 0.001, OR: 26.8, 95% CI 2-1,478). The median progression-free survival times were 5.8 months (95% CI 2.8-8.8) and 28.7 months (95% CI 13.4-43.9) in the groups with detectable and undetectable e-IL-10, respectively (p < 0.001). DISCUSSION: Our results suggest that despite an objective response, the persistence of detectable e-IL-10 is associated with a high risk of early relapse in PCNSL. A closer follow-up of such patients is warranted.

Hepatosplenic Candidiasis in Patients With Hematological Malignancies: A 13-Year Retrospective Cohort Study.

Background: Hepatosplenic candidiasis (HSC) used to be reported in patients with acute myeloid leukemia (AML) without antifungal prophylaxis. The aim was to describe the clinical features and outcomes of HSC over the last 13 years in a single French hematology center. Methods: All patients diagnosed with HSC between 2008 and 2020 were included in a single-center retrospective cohort study. Data were collected from patient charts, and HSC was classified according to the 2020 European Organisation for Research and Treatment of Cancer/Mycoses Study Group definitions. Results: Sixty patients were included, with 18.3% proven, 3.3% probable, and 78.3% possible HSC according to the 2020 European Organization for Research and Treatment of Cancer Mycoses Study Group classification. Among them, 19 patients were treated for acute myeloid leukemia (AML), 21 for lymphomas, and 14 for acute lymphoblastic leukemia. HSC occurred in 13 patients after autologous stem cell transplantation for lymphoma. At HSC diagnosis, 13 patients were receiving antifungal prophylaxis. Candida colonization was present in 84.2%, with prior candidemia in 36.7% of cases. ß-D-glucans was positive in 55.8%, and 45.8% of tissue biopsies were contributive. First-line antifungal therapy was azoles in 61.7%, and steroids were associated in 45% of cases. At 3 months of follow-up, partial response to antifungal therapy was 94.2%. At last follow-up (mean, 22.6 months), 41 patients (68.3%) presented a complete hematological remission and 22 patients were deceased, none because of HSC. Conclusions: The epidemiology of HSC has changed in the last decade, with fewer cases occurring in the AML setting. A better identification of patients at risk could lead to specific prophylaxis and improved diagnosis.

FLAMSA-Busulfan-Melphalan as a Sequential Conditioning Regimen in HLA-Matched or Haploidentical Hematopoietic Stem Cell Transplantation for High-Risk Myeloid Diseases.

Given the poor prognosis of relapsed/refractory myeloid malignancies, the concept of sequential conditioning before allogeneic hematopoietic stem cell transplantation (allo-HSCT) has proven to be an effective approach. We sought to evaluate a sequential scheme combining fludarabine, amsacrine, and cytarabine (FLAMSA) for cytoreduction, followed by reduced-intensity conditioning with busulfan and melphalan (FLAMSA-BuMel), which was designed to be suitable for both HLA-matched and haploidentical HSCT. This single-center retrospective study included 36 adult patients with high-risk myeloid malignancies who underwent allo-HSCT from HLA-matched (n = 19) or haploidentical (n = 17) donors. Along with the standard prophylaxis for graft-versus-host disease (GVHD), patients with a haploidentical donor received post-transplantation high-dose cyclophosphamide. A post-transplantation consolidation treatment with low-dose 5-azacytidine and prophylactic donor lymphocyte infusions was provided whenever possible. Thirty patients (83%) achieved complete remission on day +30. With a median follow-up of 30.0 months, the 2-year overall survival was 89% in the HLA-matched group versus 34% in the haploidentical group (P = .0018). The 2-year disease-free survival in these 2 groups was 68% and 34%, respectively (P = .013). At 2 years, the probability of relapse was 32% and 20%, respectively, and nonrelapse mortality was 0% and 58%, respectively (P = .0003). The leading cause of death was relapse in the HLA-matched group (3 of 19) and hemorrhagic events (5 of 17) in the haploidentical group, favored by significantly delayed platelet reconstitution and a severe GVHD context. These data confirm the feasibility of FLAMSA-BuMel as a sequential conditioning in allo-HSCT for high-risk myeloid malignancies. The use of bone marrow as the preferred graft source might reduce the incidence of acute GVHD and nonrelapse mortality in the haploidentical transplantation setting.

Pre-emptive rituximab treatment for Epstein-Barr virus reactivation after allogeneic hematopoietic stem cell transplantation is a worthwhile strategy in high-risk recipients: a comparative study for immune recovery and clinical outcomes.

This retrospective study evaluated the impact of a pre-emptive rituximab (RTX) strategy for Epstein-Barr virus (EBV) reactivation on immune recovery and outcomes of 219 high-risk recipients undergoing allogeneic stem cell transplantation (allo-SCT) for hematological malignancies or bone marrow failure. One-hundred and seven patients received pre-emptive RTX for EBV reactivation (RTX group) and 112 did not (control group). The median onset time of EBV reactivation was 49 days (range, 14-561), including five patients who developed post-transplant lymphoproliferative disorder (EBV-PTLD). RTX and control groups were pair-matched to assess the impact of RTX on all endpoints. In RTX patients, CD19 + B cells were significantly decreased until 1-year post-transplant, so were immunoglobulin levels. Twenty-one patients (17%) developed RTX-related neutropenia. There was, in the RTX group, a trend towards a lower cumulative incidence of chronic GvHD (P = 0.059). Overall survival, progression-free survival, non-relapse mortality, relapse incidence, and incidence of overall infections at 2 years following allo-SCT were comparable in the two groups. We conclude that pre-emptive RTX, despite inducing a delayed B-cell reconstitution and a high risk of RTX-related neutropenia, may be considered as a worthwhile treatment, given the absence of negative impact on post allo-SCT outcomes and a low incidence of EBV-PTLD.

Quantitative and functional alterations of 6-sulfo LacNac dendritic cells in multiple myeloma.

Multiple myeloma (MM) results from expansion of abnormal plasma cells in the bone marrow (BM). Previous studies have shown that monocytes play a crucial role in MM pathophysiology. A 6-sulfo LacNAc-expressing population of dendritic cells (Slan-DCs) that overlaps with intermediate and non-classical monocytes in terms of phenotype has been described. Slan-DCs represent a circulating and tissue proinflammatory myeloid population which has been shown to play a role in different cancer contexts, and which exhibits a remarkable plasticity. Herein, we studied Slan-DCs from the BM and blood of MM patients. We performed quantitative and functional analyses of these cells from 54 patients with newly diagnosed, symptomatic MM, 21 patients with MGUS and 24 responding MM patients. We found that circulating Slan-DCs were significantly decreased in MM patients as compared to those of healthy donors or patients with MGUS, while CD14+CD16+ intermediate monocytes accumulate in the BM. Moreover, after activation with TLR7/8 ligand R848, IL-12-producing Slan-DCs from the BM or peripheral blood from MM patients were decreased as compared with healthy donors. We show that MM cell lines or MM cells isolated from patients at diagnosis were able to inhibit the production of IL-12 by Slan-DCs, as well as to shift the phenotype of Slan-DCs towards an intermediate monocyte-like phenotype. Finally, Slan-DCs that have been cultured with MM cells reduced their capacity to induce T cell proliferation and Th1 polarization. We conclude that Slan-DCs represent previously unrecognized players in MM development and may represent a therapeutic target.