[Rinsho ketsueki] The Japanese journal of clinical hematology最新文献

Advances in replacement therapy with clotting factor (F) VIII or FIX product have contributed greatly to reducing the incidence of hemophilic arthropathy and improving quality of life (QOL) in patients with hemophilia. However, frequent intravenous administration of clotting factor products, blood access, and development of alloantibodies (inhibitors) have been important issues. Clinical studies aimed at addressing these issues have been conducted in Japan as well, including a multicenter study to determine factors involved in inhibitor development. Drug development has also progressed: several clotting factor products with extended half-life and non-clotting factor therapies have been introduced in quick succession. Anti-FIX/FX bispecific antibody in particular has a long half-life when administered subcutaneously and controls bleeding in patients with hemophilia A. Anti-antithrombin therapy and anti-TFPI monoclonal antibody products that work by rebalancing coagulation have also been developed. In addition, gene therapy has been approved for adults in U.S. and Europe, where improved vectors and codon optimization have enabled protein expression up to the near-therapeutic hemostatic range. Recent significant developments in hemophilia treatment are expected to overcome long-standing problems and further improve QOL.

Chimeric antigen receptor (CAR) T-cell therapy is an innovative treatment for B-cell malignancies and multiple myeloma. CAR T-cell therapy is now approved in Japan and has become one of the essential therapeutic options for chemotherapy-resistant disease. It has many unique features that distinguish it from conventional chemotherapies, including the limitations imposed by the production of CAR-T cells from autologous T cells, and the limited availability and mandatory waiting period for treatment. Importantly, each patient has only one opportunity to receive CAR T-cell therapy. To achieve the maximum therapeutic benefit from CAR T-cell therapy, it is necessary to understand all aspects of CAR T-cell therapy, including factors that influence its efficacy. The design of the entire treatment sequence, including before and after CAR T-cell therapy, is also important to optimize clinical outcomes. In addition, since this treatment is only available at a limited number of facilities, effective coordination between local hospitals and treatment centers is also important. This educational session will focus on the practical aspects of CAR T-cell therapy in adults and will provide indispensable knowledge for providing CAR T-cell therapy to patients with B-cell lymphoma and multiple myeloma.

Immunomodulatory drugs (IMiDs), proteasome inhibitors (PIs), and anti-CD38 antibodies have been the three mainstays of myeloma treatment. B-cell maturation antigen (BCMA)-targeted immunotherapy, including chimeric antigen receptor T-cell therapy (CAR-T) and bispecific antibodies (BsAbs), is emerging as another important class of treatment. Two BCMA-targeting CAR-T products, idecabtagene vicleucel (ide-cel) and ciltacabtagene autoleucel, are approved in Japan, but only ide-cel is available for clinical use. Recently, a randomized phase III study comparing ide-cel with standard therapy in patients with refractory myeloma who had received 2 to 4 prior lines of therapy showed that ide-cel was superior in terms of both response rate and PFS. Based on these results, ide-cel was approved as a third-line therapy. The new availability of bispecific antibodies has also raised new clinical questions regarding how to use CAR-T and BsAbs for each patient, and in what order. Limited data have suggested that favorable responses can be achieved when BsAbs are administered after CAR-T, but responses are suboptimal when CAR-T is administered after BsAbs. Finally, it is important to note that coordination between referring centers and treating centers, including aspects such as timing of patient referral, bridging therapy, and long-term follow-up after CAR-T, is critical to optimization of CAR-T.

An 80-year-old Japanese man presented with systemic lymphadenopathy, including the para-aortic area and left inguinal nodes, which was diagnosed as diffuse large B-cell lymphoma (DLBCL) and human herpesvirus (HHV) 8-positive/HIV-negative Kaposi's sarcoma (KS). Immunohistochemical examination revealed that the lymphoma cells were negative for HHV-8. The patient received combined chemotherapy with rituximab, pirarubicin, cyclophosphamide, vincristine, and prednisolone for six cycles and achieved complete remission. In the literature, five cases of simultaneous appearance of malignant lymphoma and KS in the same lymph node have been reported, but DLBCL as a histological subtype has not yet been reported.

A 47-year-old woman presented with subcutaneous hemorrhage. Blood tests revealed leukoerythroblastosis, anemia, and thrombocytopenia. Bone marrow biopsy led to a diagnosis of primary myelofibrosis (aaDIPSS, DIPSS-plus: intermediate-II risk). JAK2, CALR, and MPL mutations were not detected in peripheral blood, but targeted sequencing of bone marrow specimens revealed a double mutation (Q157R, S34F) in U2AF1. Allo-PBSCT was performed using an HLA-matched related donor, and post-transplantation bone marrow examination showed complete donor chimerism on day 55. Two years after allogeneic transplantation, the patient remains relapse-free. Although U2AF1 gene abnormality is known as a poor prognostic factor in primary myelofibrosis, this patient had a favorable long-term prognosis due to prompt transplantation therapy. This case highlights the importance of detailed gene mutation analysis in patients with triple-negative MF.

Patient 1 was a 70-year-old woman with refractory diffuse large B-cell lymphoma who received allogeneic peripheral blood stem cell transplantation from an HLA-haploidentical related donor. Upper back pain appeared on day63, and Th8-Th9 pyogenic spondylitis was diagnosed based on magnetic resonance imaging (MRI). Blood culture on day14 identified Corynebacterium striatum as the causative bacteria of blood stream infection (BSI). The pyogenic spondylitis resolved after treatment with daptomycin for 2 months. Patient 2 was a 65-year-old man with relapsed angioimmunoblastic T-cell lymphoma who received bone marrow transplantation from an HLA-DR single-antigen-mismatched unrelated donor. Lower back pain appeared on day30, and L4-L5 pyogenic spondylitis was diagnosed based on MRI. Blood culture was negative. Daptomycin and clindamycin were selected for treatment based on the drug susceptibility of bacteria that had caused pre-engraftment BSI (Escherichia coli on day3 and Corynebacterium striatum on day9), and the pyogenic spondylitis resolved after 6 months of this treatment. Pyogenic spondylitis should be considered in the differential diagnosis of back pain accompanied by BSI before engraftment in allogeneic hematopoietic stem cell transplant recipients.

Myelodysplastic syndrome (MDS) is a refractory cancer that arises from hematopoietic stem cells and predominantly affects elderly adults. In addition to driver gene mutations, which are also found in clonal hematopoiesis in healthy elderly people, systemic inflammation caused by infection or collagen disease has long been known as an extracellular factor in the pathogenesis of MDS. Wild-type HSCs have an "innate immune memory" that functions in response to infection and inflammatory stress, and my colleagues and I used an infection stress model to demonstrate that the innate immune response by the TLR-TRIF-PLK-ELF1 pathway is similarly critical in impairment of hematopoiesis and dysregulation of chromatin in MDS stem cells. This revealed that not only are MDS stem cells expanded by the TRAF6-NF-kB pathway, the innate immune response is also involved in generating MDS stem cells. In this review, I will present research findings related to "innate immune memory," one of the pathogenic mechanisms of blood cancer, and discuss future directions for basic pathological research and potential therapeutic development.

Many novel agents have been developed for BCR::ABL1-negaive myeloproliferative neoplasms (MPN), namely, polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). Some of these agents not only achieve hematologic complete response, reduce spleen size, and alleviate constitutional symptoms, but also induce molecular response, which means that they reduce the allele burden of driver gene mutations. These agents also prevent and alleviate fibrosis in bone marrow, which reduces the incidence of thrombotic events and disease progression and might improve prognosis. This article discusses the latest findings and promising treatments, including ongoing clinical trials, in PV, ET, and PMF.