Five-year follow-up of KEYNOTE-087: pembrolizumab monotherapy for relapsed/refractory classical Hodgkin lymphoma.

Previous analyses of the phase 2 KEYNOTE-087 (NCT02453594) trial of pembrolizumab monotherapy demonstrated effective antitumor activity with acceptable safety in patients with relapsed or refractory (R/R) classical Hodgkin lymphoma (cHL). However, long-term response durability and outcome of patients who receive a second course after treatment discontinuation after complete response (CR) remain of clinical interest. We present KEYNOTE-087 data after >5 years of median follow-up. Patients with R/R cHL and progressive disease (PD) after autologous stem cell transplantation (ASCT) and brentuximab vedotin (BV; cohort 1), salvage chemotherapy and BV without ASCT (cohort 2), or ASCT without subsequent BV (cohort 3), received pembrolizumab for ≤2 years. Patients in CR who discontinued treatment and subsequently experienced PD were eligible for second-course pembrolizumab. Primary end points were the objective response rate (ORR) using blinded central review and safety. The median follow-up was 63.7 months. ORR was 71.4% (95% confidence interval [CI], 64.8-77.4; CR, 27.6%; partial response, 43.8%). Median duration of response (DOR) was 16.6 months; median progression-free survival was 13.7 months. A quarter of responders, including half of complete responders, maintained a response for ≥4 years. Median overall survival was not achieved. Among 20 patients receiving second-course pembrolizumab, ORR for 19 evaluable patients was 73.7% (95% CI, 48.8-90.8); median DOR was 15.2 months. Any-grade treatment-related adverse events occurred in 72.9% of patients and grade 3 or 4 adverse events occurred in 12.9% of patients; no treatment-related deaths occurred. Single-agent pembrolizumab can induce durable responses, particularly in patients achieving CR. Second-course pembrolizumab frequently reinduced sustained responses after relapse from initial CR.

Frequent genetic alterations in immune checkpoint-related genes in intravascular large B-cell lymphoma.

Intravascular large B-cell lymphoma (IVLBCL) is a unique type of extranodal lymphoma characterized by selective growth of tumor cells in small vessels without lymphadenopathy. Greater understanding of the molecular pathogenesis of IVLBCL is hampered by the paucity of lymphoma cells in biopsy specimens, creating a limitation in obtaining sufficient tumor materials. To uncover the genetic landscape of IVLBCL, we performed whole-exome sequencing (WES) of 21 patients with IVLBCL using plasma-derived cell-free DNA (cfDNA) (n = 18), patient-derived xenograft tumors (n = 4), and tumor DNA from bone marrow (BM) mononuclear cells (n = 2). The concentration of cfDNA in IVLBCL was significantly higher than that in diffuse large B-cell lymphoma (DLBCL) (P < .0001) and healthy donors (P = .0053), allowing us to perform WES; most mutations detected in BM tumor DNA were successfully captured in cfDNA and xenograft. IVLBCL showed a high frequency of genetic lesions characteristic of activated B-cell-type DLBCL, with the former showing conspicuously higher frequencies (compared with nodal DLBCL) of mutations in MYD88 (57%), CD79B (67%), SETD1B (57%), and HLA-B (57%). We also found that 8 IVLBCL (38%) harbored rearrangements of programmed cell death 1 ligand 1 and 2 (PD-L1/PD-L2) involving the 3' untranslated region; such rearrangements are implicated in immune evasion via PD-L1/PD-L2 overexpression. Our data demonstrate the utility of cfDNA and imply important roles for immune evasion in IVLBCL pathogenesis and PD-1/PD-L1/PD-L2 blockade in therapeutics for IVLBCL.

[Usefulness of liquid biopsy technology in clinical practice of malignant lymphoma].

Information about genetic mutations that accumulate in each subtype of malignant lymphoma has been reported. Identification of mutations is predicted to become more crucial not only for a definitive diagnosis but also for selecting effective targeted therapies and analyzing detectable residual diseases. However, in the clinical environment of malignant lymphoma, DNA samples might be difficult to obtain, and longitudinal sample collection throughout disease development and/or remission is exceedingly difficult compared to leukemia sectors. Liquid biopsy is a new strategy of tumor biopsy that detects aberrant tumor-derived genes from a patient's plasma, cerebrospinal fluid, or other body fluids. With advances in genetic analysis methods, reports are accumulating on the usefulness of liquid biopsy in diffuse large B-cell lymphoma, central nerves system lymphoma, Hodgkin lymphoma, and other types of lymphoma. This method has the potential to significantly change the way of ML diagnosis and followed up in daily practice, and its development is a great deal of attention.

Pembrolizumab in relapsed or refractory Hodgkin lymphoma: 2-year follow-up of KEYNOTE-087.

Programmed death-1 inhibitors are approved for patients with relapsed or refractory classic Hodgkin lymphoma (RRcHL). We present the 2-year follow-up of the phase 2 KEYNOTE-087 study of pembrolizumab in 210 patients, based on HL progression after autologous stem cell transplantation (ASCT) and subsequent brentuximab vedotin (BV; cohort 1); salvage chemotherapy and BV, with ineligibility for SCT owing to chemorefractory disease (cohort 2); and progression after SCT without BV (cohort 3). With a median follow-up of 27.6 months, the objective response rate (ORR) by blinded independent central review was 71.9% (95% CI, 65.3-77.9), the complete response rate (CRR) was 27.6%, and the partial response (PR) rate was 44.3%. Median duration of response was 16.5 months (range, 0.0+ to 27.0+ [+, no progressive disease at last assessment]) in all patients, 22.1 months in cohort 1, 11.1 months in cohort 2, and 24.4 months in cohort 3. Median progression-free survival was not reached in all patients with CR: 13.8 months (95% CI, 12.0-22.1) for patients with PR and 10.9 months (95% CI, 5.6-11.1) for patients with stable disease. Median overall survival was not reached in all patients or in any cohort. Treatment-related adverse events (TRAEs) of any grade occurred in 153 (72.9%) patients; grades 3 and 4 occurred in 25 (12.0%) patients; none resulted in death. Results confirmed effective antitumor activity, durability of response, and manageable safety of pembrolizumab monotherapy in RRcHL, regardless of prior treatment and including chemoresistant cHL. This trial was registered at www.clinicaltrials.gov as #NCT02453594.

Prolonged incubation period of hepatitis B in a recipient of a nucleic acid amplification test-negative hepatitis B virus window donation.

BACKGROUND: The occurrence of transfusion-transmitted hepatitis B virus (HBV) infection has fallen dramatically due to continuous improvements in pre-transfusion laboratory testing. However, the characteristics of transfusion-transmitted HBV infection caused by individual donor nucleic acid amplification test (ID-NAT)-negative blood products are unclear. CASE PRESENTATION: A 76-year-old woman with acute myeloid leukemia was diagnosed with transfusion-transmitted HBV infection after receiving apheresis platelets derived from an ID-NAT-negative blood donation. This case was diagnosed definitively as transfusion-mediated because complete nucleotide homology of a 1556 bp region of the HBV Pol/preS1-preS2-S genes and a 23 bp region of the HBV core promoter/precore between the donor and recipient strains was confirmed by PCR-directed sequencing. The case is uncommon with respect to the unexpectedly prolonged HBV-DNA incubation period of nearly 5 months after transfusion (previously, the longest period observed since the recent implementation of ID-NAT pre-transfusion laboratory testing in Japan was 84 days). Slow-replicating HBV genotype A2 may contribute to the prolonged incubation period; also, the quantity of apheresis platelets delivered in a large volume of plasma, and/or the immune response of the recipient suffering from a hematological neoplasm, may have contributed to establishment of HBV infection in the recipient. This was supported by analysis of three previously documented cases of transfusion-transmitted HBV infection by blood products derived from ID-NAT-negative donations in Japan. CONCLUSION: Continuous monitoring of HBV infection for longer periods (>3 months) may be required after transfusion of blood components from an ID-NAT-negative HBV window donation.

Primary central nervous system lymphomas with massive intratumoral hemorrhage: Clinical, radiological, pathological, and molecular features of six cases.

Primary central nervous system lymphomas (PCNSLs) rarely exhibit intratumoral hemorrhage. The differential diagnosis of hemorrhagic neoplasms of the central nervous system (CNS) currently includes metastatic carcinomas, melanomas, choriocarcinomas, oligodendrogliomas, and glioblastomas. Here we present the clinical, radiological, pathological, and molecular genetic features of six cases of PCNSL associated with intratumoral hemorrhage. The median age of patients was 75 years, with male predominance. While conventional PCNSLs were associated with low cerebral blood volume (CBV), perfusion magnetic resonance imaging (MRI) revealed elevated CBV in three cases, consistent with vascular proliferation. All six cases were diagnosed pathologically as having diffuse large B-cell lymphoma (DLBCL) with a non-germinal center B-cell-like (non-GCB) phenotype; marked histiocytic infiltrates and abundant non-neoplastic T-cells were observed in most cases. Expression of vascular endothelial growth factor and CD105 in the lymphoma cells and the small vessels, respectively, suggested angiogenesis within the neoplasms. Neoplastic cells were immunohistochemically negative for programmed cell death ligand 1 (PD-L1), while immune cells in the microenvironment were positive for PD-L1. Mutations in the MYD88 gene (MYD88) (L265P) and the CD79B gene (CD79B) were detected in five and one case, respectively. As therapeutic modalities used for PCNSLs differ from those that target conventional hemorrhagic neoplasms, full tissue diagnoses of all hemorrhagic CNS tumors are clearly warranted.

Allogeneic hematopoietic stem cell transplantation at the first remission for younger adults with FLT3-internal tandem duplication AML: The JALSG AML209-FLT3-SCT study.

In this phase II multicenter study (JALSG AML209-FLT3-SCT), we aimed to prospectively elucidate the role of allogeneic hematopoietic stem cell transplantation (allo-HSCT) at first complete remission (CR1) for FLT3-internal tandem duplication (ITD)-positive AML. Newly diagnosed de novo AML patients with FLT3-ITD were enrolled at the achievement of CR1 and received allo-HSCT as soon as possible after the first consolidation therapy. Mutations of 57 genes in AML cells at diagnosis were also analyzed. Among 48 eligible patients with a median age of 38.5 (17-49) years, 36 (75%) received allo-HSCT at a median of 108 days after CR1. The median follow-up was 1726 days. The primary end-point, 3-year disease-free survival (DFS) based on an intent to treat analysis, was 43.8% (95% confidence interval [CI], 30%-57%), suggesting the efficacy of this treatment because the lower limit of the 95% CI exceeded the threshold response rate of 20%. The 3-year overall survival, post-transplant DFS, and non-relapse mortality rates were 54.2% (95% CI, 39%-67%), 58.3% (95% CI, 41%-72%), and 25.0% (95% CI, 12%-40%), respectively. The median ITD allelic ratio (AR) was 0.344 (0.006-4.099). Neither FLT3-ITD AR nor cooccurring genetic alterations was associated with a poor DFS. This prospective study indicated the efficacy and safety of allo-HSCT for FLT3-ITD AML patients in CR1. This study was registered at: www.umin.ac.jp/ctr/ as #UMIN000003433.

Clinical utility of target capture-based panel sequencing in hematological malignancies: A multicenter feasibility study.

Although next-generation sequencing-based panel testing is well practiced in the field of cancer medicine for the identification of target molecules in solid tumors, the clinical utility and clinical issues surrounding panel testing in hematological malignancies have yet to be fully evaluated. We conducted a multicenter prospective clinical sequencing study to verify the feasibility of a panel test for hematological tumors, including acute myeloid leukemia, acute lymphoblastic leukemia, multiple myeloma, and diffuse large B-cell lymphoma. Out of 96 eligible patients, 79 patients (82%) showed potentially actionable findings, based on the clinical sequencing assays. We identified that genetic alterations with a strong clinical significance were found at a higher frequency in terms of diagnosis (n = 60; 63%) and prognosis (n = 61; 64%) than in terms of therapy (n = 8; 8%). Three patients who harbored a germline mutation in either DDX41 (n = 2) or BRCA2 (n = 1) were provided with genetic counseling. At 6 mo after sequencing, clinical actions based on the diagnostic (n = 5) or prognostic (n = 3) findings were reported, but no patients were enrolled in a clinical trial or received targeted therapies based on the sequencing results. These results suggest that panel testing for hematological malignancies would be feasible given the availability of useful diagnostic and prognostic information. This study is registered with the UMIN Clinical Trial Registry (UMIN000029879, multiple myeloma; UMIN000031343, adult acute myeloid leukemia; UMIN000033144, diffuse large B-cell lymphoma; and UMIN000034243, childhood leukemia).

Ultra-high sensitivity HBsAg assay can diagnose HBV reactivation following rituximab-based therapy in patients with lymphoma.

BACKGROUND & AIMS: HBV reactivation is a risk in patients receiving anti-CD20 antibodies for the treatment of lymphoma. The purpose of this post hoc analysis was to evaluate the efficacy of an ultra-high sensitivity HBsAg assay to guide preemptive antiviral treatment in patients with lymphoma and resolved HBV infections using prospectively stored samples from an HBV DNA monitoring study. METHODS: HBV reactivation (defined as HBV DNA levels of ≥11 IU/ml) was confirmed in 22 of 252 patients. A conventional HBsAg assay (ARCHITECT, cut-off value: 0.05 IU/ml) and an ultra-high sensitivity HBsAg assay employing a semi-automated immune complex transfer chemiluminescence enzyme technique (ICT-CLEIA, cut-off value: 0.0005 IU/ml) were performed at baseline, at confirmed HBV reactivation and monitored after HBV reactivation. RESULTS: Baseline HBsAg was detected using ICT-CLEIA in 4 patients; in all of whom precore mutants with high replication capacity were reactivated. Of the 6 patients with HBV DNA detected below the level of quantification at baseline, 5 showed HBV reactivation and 3 of the 5 had precore mutations. Sensitivity for detection by ARCHITECT and ICT-CLEIA HBsAg assays at HBV reactivation or the next sampling after HBV reactivation was 18.2% (4 of 22) and 77.3% (17 of 22), respectively. Of the 5 patients undetectable by ICT-CLEIA, HBV reactivation resolved spontaneously in 2 patients. All 6 patients reactivated with precore mutations including preS deletion could be diagnosed by ICT-CLEIA HBsAg assay at an early stage of HBV reactivation. Multivariate analysis showed that an anti-HBs titer of less than 10 mIU/ml, HBV DNA detected but below the level of quantification, and HBsAg detected by ICT-CLEIA at baseline were independent risk factors for HBV reactivation (adjusted hazard ratios, 15.4, 31.2 and 8.7, respectively; p <0.05). CONCLUSIONS: A novel ICT-CLEIA HBsAg assay is an alternative method to diagnose HBV reactivation. CLINICAL TRIAL NUMBER: UMIN000001299. LAY SUMMARY: Hepatitis B virus can be reactivated in lymphoma patients receiving anti-CD20 antibodies such as rituximab. Currently, reactivation requires the monitoring of HBV DNA, but monitoring of the surface antigen (HBsAg) could provide a relatively inexpensive, quick and easy alternative. We assessed the performance of an ultra-high sensitivity HBsAg assay and showed that it could be effective for the diagnosis and monitoring of HBV reactivation.

Truncated RUNX1 Generated by the Fusion of RUNX1 to Antisense GRIK2 via a Cryptic Chromosome Translocation Enhances Sensitivity to Granulocyte Colony-Stimulating Factor.

Fusions of the Runt-related transcription factor 1 (RUNX1) with different partner genes have been associated with various hematological disorders. Interestingly, the C-terminally truncated form of RUNX1 and RUNX1 fusion proteins are similarly considered important contributors to leukemogenesis. Here, we describe a 59-year-old male patient who was initially diagnosed with acute myeloid leukemia, inv(16)(p13;q22)/CBFB-MYH11 (FAB classification M4Eo). He achieved complete remission and negative CBFB-MYH11 status with daunorubicin/cytarabine combination chemotherapy but relapsed 3 years later. Cytogenetic analysis of relapsed leukemia cells revealed CBFB-MYH11 negativity and complex chromosomal abnormalities without inv(16)(p13;q22). RNA-seq identified the glutamate receptor, ionotropic, kinase 2 (GRIK2) gene on 6q16 as a novel fusion partner for RUNX1 in this case. Specifically, the fusion of RUNX1 to the GRIK2 antisense strand (RUNX1-GRIK2as) generated multiple missplicing transcripts. Because extremely low levels of wild-type GRIK2 were detected in leukemia cells, RUNX1-GRIK2as was thought to drive the pathogenesis associated with the RUNX1-GRIK2 fusion. The truncated RUNX1 generated from RUNX1-GRIK2as induced the expression of the granulocyte colony-stimulating factor (G-CSF) receptor on 32D myeloid leukemia cells and enhanced proliferation in response to G-CSF. In summary, the RUNX1-GRIK2as fusion emphasizes the importance of aberrantly truncated RUNX1 in leukemogenesis.

Predictors of early death, serious hemorrhage, and differentiation syndrome in Japanese patients with acute promyelocytic leukemia.

Significant advancements have been achieved with regard to the outcomes of acute promyelocytic leukemia (APL) patients through the introduction of all-trans retinoic acid; however, early hemorrhagic death and differentiation syndrome remain the major causes of remission induction failure in patients with APL. To investigate early death, serious hemorrhage, and differentiation syndrome during remission induction therapy in terms of incidence, risk factors, influence on outcomes, and prophylactic effects of several new anticoagulants, the results of 344 patients enrolled in the Acute Promyelocytic Leukemia 204 study conducted by the Japan Adult Leukemia Study Group were analyzed. Early death was observed in 16 patients (4.7%), of whom 14 had serious hemorrhage and 2 had differentiation syndrome. Serious hemorrhage and differentiation syndrome of grade 2 or higher were observed in 21 and 54 patients, respectively. Patients who achieved complete remission had a 7-year disease-free survival of 84.8% if they did not experience serious hemorrhage and 40.0% if they experienced serious hemorrhage during remission induction therapy (P = 0.001). Risk factor analyses showed that higher white blood cell count was associated with early death, higher white blood cell count and lower platelet count with serious hemorrhage, and leukocytosis during induction therapy and higher body surface area with differentiation syndrome. In conclusion, these results indicate that patients with such high-risk features may benefit from more intensive supportive care. The hemorrhagic risk was not relieved by the introduction of new anticoagulants. Further studies are required to establish the predictive impact of body surface area on differentiation syndrome. This trial is registered with UMIN-CTR as C000000154 on September 13, 2005.

[Advances in antibody therapy for B cell lymphoma].

Almost 20 years have passed after rituximab, an anti-CD20 mouse-human chimeric monoclonal antibody therapeutic, was introduced in the clinical setting for the treatment of CD20-positive B cell malignancies. Although the prognosis has significantly improved in most B cell malignancies, resistance to rituximab with/without chemotherapies is also widely recognized. With this background, newer generation antibody therapeutics and other molecular targeting drugs that show more effectiveness especially to refractory patients are critically required. In this review, molecular mechanisms of the second/third generation anti-CD20 antibodies (ofatumumab and obinutuzumab), anti-CD19 chimeric antigen-receptor T-cells (CAR-T-CD19; tisagenlecleucel, axicabtagene ciloleucel), and the anti-PD-1 antibodies (nivolumab and pembrolizumab) are presented. The therapeutic effectiveness of those drugs as monotherapy and/or combined therapy with conventional chemotherapy (immunochemotherapy) and another molecular targeting therapeutics (so-called "chemo-free" regimens) are also reviewed.

Pyruvate secreted from patient-derived cancer-associated fibroblasts supports survival of primary lymphoma cells.

Cancer-associated fibroblasts (CAF) are a key component in the tumor microenvironment and play functional roles in tumor metastasis and resistance to chemotherapies. We have previously reported that CAF isolated from lymphoma samples increase anaerobic glycolysis and decrease intracellular production of reactive oxygen species, promoting the survival of tumor cells. Herein, we analyzed the mechanisms underlying this support of tumor-cell survival by CAF. As direct contact between lymphoma cells and CAF was not indispensable to survival support, we identified that the humoral factor pyruvate was significantly secreted by CAF. Moreover, survival of lymphoma cells was promoted by the presence of pyruvate, and this promotion was canceled by inhibition of monocarboxylate transporters. Metabolome analysis of lymphoma cells in coculture with CAF demonstrated that intermediates in the citric acid cycle were significantly increased, indicating that tumor cells produced energy by aerobic metabolism. These findings indicate that energy production in lymphoma cells is regulated in coordination not only with anaerobic glycolysis, but also with aerobic metabolism termed the reverse-Warburg effect, involving the secretion of pyruvate from CAF resulting in increased use of the citric acid cycle in lymphoma cells.

Effect of L-Leucine Therapy on Hematopoietic Function in Elderly Myelodysplastic Syndrome Patients.

Patients with myelodysplastic syndrome (MDS) often require blood transfusion and anticancer therapy; however, elderly patients are intolerant to the associated side effects of anticancer therapy. Because L-leucine can be used to treat Diamond-Blackfan anemia, which is caused by defects in ribosomal protein (RP) genes, resulting in increased in vivo hemoglobin synthesis, it is possible that some MDS patients who have aberrations in their RP genes could also be effectively treated with L-leucine. In the present study, we investigated the effects of L-leucine on hematopoietic function (reticulocyte count), red blood cell count, and hemoglobin level in MDS patients. We administered L-leucine (1.8 g, twice daily, 3 d/week) with oral vitamin B6 supplements to a final cohort of eight MDS patients for 15 (interquartile range: 11-18) weeks. We assessed the patients at 10 ± 2 weeks after therapy initiation. Only the absolute reticulocyte count was affected, improving in 6/8 (75%) patients. The median absolute reticulocyte count was 3.5 × 104 (range: 2.7-6.4 × 104) cells/µL, an increase of 0.5 × 104 (range: 0.2-0.7 × 104) cells/µL. At 10 weeks, there was only one case of an improved hemoglobin level. Non-hematological adverse events of grade 3 were observed one raised triglycerides. These data suggest that L-leucine has little effect on MDS. However, it may contribute to the recovery of hematopoietic function, futher study be desired.

Intratumoral evaluation of 3D microvasculature and nanoparticle distribution using a gadolinium-dendron modified nano-liposomal contrast agent with magnetic resonance micro-imaging.

The enhanced permeability and retention (EPR) effect is variable depending on nanoparticle properties and tumor/vessel conditions. Thus, intratumoral evaluations of the vasculature and nanoparticle distribution are important for predicting the therapeutic efficacy and the intractability of tumors. We aimed to develop a tumor vasculature evaluation method and high-resolution nanoparticle delivery imaging using magnetic resonance (MR) micro-imaging technology with a gadolinium (Gd)-dendron assembled liposomal contrast agent. Using the Gd-liposome and a cryogenic receiving coil, we achieved 50-µm isotropic MR angiography with clear visualization of tumor micro-vessel structure. The Gd-liposome-enhanced MR micro-imaging revealed differences in the vascular structures between Colon26- and SU-DHL6-grafted mice models. The vessel volumes and diameters measured for both tumors were significantly correlated with histological observations. The MR micro-imaging methods facilitate the evaluation of intratumoral vascularization patterns, the quantitative assessment of vascular-properties that alter tumor malignancy, particle retentivity, and the effects of treatment.

A nationwide survey of hypoplastic myelodysplastic syndrome (a multicenter retrospective study).

Hypoplastic myelodysplastic syndrome (hMDS) is a distinct entity with bone marrow (BM) hypocellularity and the risk of death from BM failure (BMF). To elucidate the characteristics of hMDS, the data of 129 patients diagnosed between April 2003 and March 2012 were collected from 20 institutions and the central review team of the National Research Group on Idiopathic Bone Marrow Failure Syndromes, and compared with 115 non-hMDS patients. More RA and fewer CMMoL and RAEB-t in French-American-British (FAB) and more RCUD and MDS-U and fewer RCMD in World Health Organization (WHO) classifications were found in hMDS than non-hMDS with significant differences. The overall survival (OS) and AML progression-free survival (AML-PFS) of hMDS were higher than those of non-hMDS, especially in patients at age ≥50 and of lower risk in Revised International Prognostic Scoring System (IPSS-R). In competing risks analysis, hMDS exhibited decreased risk of AML-progression in lower IPSS or IPSS-R risk patients, and higher risk of death from BMF in patients at age ≥50. Poor performance status (PS ≥2) and high karyotype risks in IPSS-R (high and very high) were significant risk factors of death and AML-progression in Cox proportional hazards analysis.