藤原 慎一郎

BACKGROUND: Sex-mismatched allogeneic hematopoietic cell transplantation (allo-HCT), particularly with female donors and male recipients (FtoM), is known to be associated with an increased risk of chronic graft-versus-host disease (GVHD) and non-relapse mortality (NRM). This adverse effect of FtoM allo-HCT is considered to result from allo-immunity against Y-chromosome antigens. However, it has not been elucidated whether the adverse impact of FtoM allo-HCT varies by recipient age. OBJECTIVE: This study aims to examine the effect of sex-mismatch on clinical outcomes in allo-HCT from human leukocyte antigen (HLA)-matched donors, stratified by recipient age group. STUDY DESIGN: Using a Japanese transplantation registry database, we analyzed 10392 patients (n = 2169, 2573, and 5650 in FtoM, MtoF, and sex-matched allo-HCT, respectively) with standard-risk hematological malignancies who had undergone their first allo-HCT from HLA-matched related or unrelated donors without in vivo T-cell depletion between 2008 and 2022. The impact of sex-mismatch on clinical outcomes was separately assessed by recipient age groups: ≤ 15, 16-39, and ≥ 40 years. The primary endpoint was overall survival (OS). Secondary endpoints included disease-free survival, NRM, and the cumulative incidences of acute and chronic GVHD. RESULTS: In recipients aged ≥ 40 years, OS and NRM at 5 years post-HCT were significantly worse in the FtoM group compared with the MtoF and sex-matched groups (5-year OS 49.5% vs 59.6% vs 57.1%, P < 0.001; 5-year NRM 27.9% vs 21.9% vs 23.0%, P < 0.001), while no differences were observed among the FtoM, MtoF, and sex-matched groups in recipients aged ≤ 15 years or 16-39 years. Multivariate analyses confirmed that FtoM allo-HCT was significantly associated with increased mortality only in recipients aged ≥ 40 years (hazard ratio [HR] for OS 1.31, P < 0.001; HR for NRM 1.44, P < 0.001). The FtoM group in recipients aged ≥ 40 years frequently experienced fatal infection and fatal non-infectious pulmonary complications. In addition, we confirmed that the adverse effect of FtoM allo-HCT on OS similarly appeared only in recipients aged ≥ 40 years in both sub-cohorts divided by a median of donor age (40 years). CONCLUSION: The adverse impact of FtoM allo-HCT on survival outcomes differed according to recipient age. Our findings suggest that female donors should be avoided, especially in older male recipients undergoing allo-HCT.

BACKGROUND: For peripheral blood stem cell (PBSC) collection of unrelated donors, the Japan Marrow Donor Program (JMDP) sets the target CD34+ cell dose as the minimum of 2 × 106 cells/kg of recipient body weight (RBW) and recommends a processing blood volume (PBV) as high as 200 mL/kg of donor body weight (DBW) with ≤250 mL/kg per day within two consecutive days. Here, we retrospectively reviewed this guideline. STUDY DESIGN AND METHODS: We analyzed 1656 unrelated donor PBSC collections between January 2012 and November 2022 from the JMDP database. RESULTS: The target CD34+ cell dose was achieved within 2 days in all but 40 cases (2.4%), suggesting that the current JMDP guideline largely meets its objectives. The distribution of PBV per DBW showed three peaks. The most prominent peak, consisting of 834 (50.4%) cases, occurred around the recommended PBV (180-220 mL/kg of DBW), whereas 659 (39.8%) cases were in the lower PBV range (<180 mL/kg), and, notably, there was no significant difference between these groups in the collected CD34+ cells/kg RBW. On the other hand, among the 163 (9.8%) cases in the higher PBV group (>220 mL/kg), the number of collected CD34+ cells/kg of RBW was significantly lower than in the other two groups. DISCUSSION: These results suggest that the target PBV in the lower and higher PBV groups was determined using CD34+ enumeration before or during apheresis procedure. CD34+ enumeration may help reduce the burden on donors, although further investigations are needed to confirm.

Previous studies have shown that the pre-transplant C-reactive protein (CRP)/platelet ratio (CP ratio) is a predictor of survival. The aim of this multicenter retrospective study was to evaluate the clinical significance of CP ratio in patients with malignant lymphoma (ML) who underwent allogeneic hematopoietic stem cell transplantation (alloHCT). The cohort included patients with ML who underwent first alloHCT from 2007 to 2021. CP ratio was defined as CRP [mg/dL]/platelet [104/μL] and evaluated prior to alloHCT. The cutoff value for CP ratio was set at 0.05 based on previous studies. A total of 311 cases were analyzed, of which 134 were mature B cell lymphoma, 177 were T/NK cell lymphoma (including 70 cases of adult T-cell leukemia/lymphoma), and 17 were Hodgkin's lymphoma. The median age was 53 years (range: 17-69 years). High CP ratio was associated with status of disease, presence of infections, poor performance status at alloHCT, and high transfusion volume received prior to alloHCT. Overall survival (OS) at 2 years according to CP ratio (low vs. high) was 61.1% versus 30.1% (p < 0.001), non-relapse mortality (NRM) was 21.4% versus 40.7% (p = 0.001), and the relapse rate was 23.7% versus 32.6% (p = 0.061), respectively. In multivariate analysis, the high CP ratio group was associated with poor OS (HR = 2.20, 95% CI: 1.61-3.02, p < 0.001) and higher NRM (HR = 1.90, 95% CI: 1.28-2.81, p = 0.0014). High CP ratio was found to be associated with poor post-transplant OS and NRM, and was a suitable prognostic biomarker for stratifying the risk of patients with ML who are candidates for alloHCT.

Allogeneic hematopoietic stem cell transplantation (HSCT) from HLA-matched donors is the gold standard. However, haploidentical stem cell transplantation using posttransplant cyclophosphamide (PTCY-haplo) and cord blood transplants (CBTs) are alternatives when HLA-matched donors are not available. Using Japanese registry data, we evaluated the impact of haploidentical donor age on posttransplant outcomes by comparing PTCY-haplo and CBT. We analyzed data for 5161 patients aged 16 to 70 years who received their first HSCT for acute leukemia, myelodysplastic syndrome, or chronic myeloid leukemia. Haploidentical donors were categorized as "younger" (aged <40 years) or "older" (aged ≥40 years), and the patients were divided into younger (aged <50 years) and older (aged ≥50 years) cohorts. In the older cohort, PTCY-haplo from younger donors had better overall survival (OS; 55.5% vs 50.8%, P = .006), lower nonrelapse mortality (NRM; 17.3% vs 28.6%, P < .001), and higher relapse rates (33.0% vs 24.9%, P = .017) than with CBT. PTCY-haplo from older donors had comparable OS (44.1% vs 50.8%, P = 1.00), NRM (27.3% vs 28.6%, P = 1.00), and relapse (29.2% vs 24.9%, P = .90) to that with CBT. In the younger cohort, PTCY-haplo from younger and older donors showed OS, NRM, and relapse comparable with CBT. In the older cohort, cumulative incidence of acute graft-versus-host disease (GVHD) was higher with CBT than with PTCY-haplo, regardless of donor age. However, in the younger cohort, acute GVHD was lower in PTCY-haplo from younger donors than with CBT. PTCY-haplo from younger donors to older patients offers better clinical outcomes than CBT.

Variation in treatment effects based on individual patient characteristics-known as treatment effect heterogeneity or effect modification-has recently gained significant attention. A previous clinical trial and its post hoc analysis suggested that letermovir (LTV) may reduce mortality more in some patients than in others. We hypothesized that the survival benefit of LTV differs according to each patient's specific characteristics. This study aimed to identify patient characteristics that are associated with significant survival benefits from LTV. Patients who underwent transplantation between 2018 and 2022 were randomly divided into training (n = 5779) and validation groups (n = 2865). We developed two models: one using a proportional hazards model with interaction terms (PI), and another using a modern machine learning (ML) approach to detect heterogeneity in the survival benefit-specifically, to identify patient characteristics associated with greater benefit from LTV. In our cohort, 60% of patients received LTV as prophylaxis. In the training cohort, the final PI model, using additive interactions, identified advanced age (≥60), high comorbidities (HCT-CI ≥3), umbilical cord blood (UCB), and haploidentical HCT with post cyclophosphamide (PTCy Haplo) as highly beneficial factors. Meanwhile, the ML model, using a causal forest algorithm, classified the top 60% of patients based on the estimated individual treatment effect as the high benefit group. In the validation group, 67.1% and 59.9% of patients were considered to be high benefit by the PI and ML models, respectively. The absolute difference in 6-month NRM (LTV versus no LTV) in the high benefit group (PI model: 9.8% versus 16.3%; ML model: 11.3% versus 16.3%) was greater than that in the low benefit group (PI model: 4.3% versus 6.9%; ML model: 4.1% versus 6.2%). Most patients (>80%) with advanced age, high comorbidities, or UCB were classified as high benefit by the ML model, supporting the robustness of the PI model. Our models successfully identified patients who could be expected to experience lower NRM with LTV prophylaxis, underscoring the importance of personalized medicine.

This phase 2 study evaluated the impact of pegfilgrastim, a single-dose, long-acting granulocyte colony-stimulating factor, on the steady-state mobilization of hematopoietic stem cells into peripheral blood in patients with multiple myeloma (MM) or malignant lymphoma (ML). Efficacy and safety, along with CD34-positive cell mobilization outcomes were assessed in patients with MM, who were randomly assigned to pegfilgrastim (n = 30) or daily filgrastim (n = 31), and ML (pegfilgrastim only, n = 13) cohorts. In the MM cohort, CD34-positive cell counts ≥ 2 × 106/kg were achieved in 100% of patients in the pegfilgrastim group and 96.7% in the filgrastim group (difference: 3.3%; 80% confidence interval: -0.9-7.5%), demonstrating the non-inferiority of pegfilgrastim to filgrastim. All patients in the ML cohort achieved ≥ 2 × 106/kg CD34-positive cell counts. The plerixafor administration rates in the MM cohort were 50.0% and 63.3% in the pegfilgrastim and filgrastim groups, respectively, and 91.7% in the ML cohort. There were no major differences in safety measures between the two groups. Although the sample size was small, particularly in the ML cohort, a single dose of pegfilgrastim demonstrated comparable efficacy and safety to daily doses of filgrastim, indicating its potential for clinical use while reducing patient burden.Trial Registration: jRCT2011210029, NCT05007652.

Influenza virus infections (IVIs) are an important cause of complications and death in immunocompromised patients, but the incidence and risk factors for IVIs in hematological diseases including benign diseases are not fully understood. We retrospectively investigated IVIs in patients with hematological diseases who visited our hematology outpatient department between 2012 and 2019. In 4,864 outpatients, 81(1.67%) IVIs were identified. The incidence of IVIs was 4.82 (95% confidence interval [CI], 3.85-5.96) per 1,000 person-years, with significantly higher rates in post-allogeneic transplant patients (21.0, 95% CI, 12.8-32.5). Progression to lower respiratory tract infection (LRTI) was observed in 7 (8.6%) of 81 patients with IVIs. In a univariate logistic regression analysis, LTRI was associated with age ≥60 years and moderate to severe chronic GVHD. Patients after hematopoietic stem cell transplantation may be at a higher risk for IVIs. Advanced age exacerbated the effects of IVIs on hematological diseases.

Rapidly progressing ALL, a potentially fatal disease, demands timely diagnosis and treatment. On the other hand, spontaneous remission/regression (SR) is reported in various cancers including aggressive tumors like ALL. Infection or trauma-mediated immune system activation is assumed to cause SR, with the duration in cases of ALL typically being short. Indolent T-lymphoblastic proliferation (i-TLP) exhibits the uniform proliferation of TdT-positive T-cells, despite being a non-neoplastic disease, underscoring the significance of distinguishing it from T-cell acute lymphoblastic leukemia (T-ALL). i-TLP is expected to gain wider recognition and further advancements in understanding its pathology. Here, we present the case of a 59-year-old woman with T-ALL characterized by cycles of progression and SR followed by a rapid blast proliferation. This is the first reported case of T-ALL with repeated SR for more than one year, making this case an extremely rare clinical presentation. This challenging case will enhance comprehension of T-cell tumor pathogenesis.

The fludarabine/intravenous busulfan 12.8 mg/kg (FB4) regimen is an effective conditioning regimen in allogeneic hematopoietic stem cell transplantation for myelodysplastic syndrome (MDS); however, limited data is available on the prognostic impact of FB4 with low-dose anti-thymoglobulin (ATG ≤ 5 mg/kg) or low-dose total body irradiation (TBI ≤ 4 Gy). Therefore, we retrospectively evaluated the outcomes in 280 adults with de novo MDS who underwent their first transplantation from an unrelated donor between 2009 and 2018. Median age was 61 years (range, 16 to 70 years). In the FB4 alone (FB4), FB4 plus ATG (FB4-ATG), and FB4 plus TBI (FB4-TBI) groups, 3-year overall survival (OS) rates were 39.9, 64.8, and 43.7 %; 3-year non-relapse mortality (NRM) were 32.1, 22.1, and 27.1%; and 3-year relapse incidences were 34.7, 21.2, and 28.9%, respectively. The multivariate analyses showed that FB4-ATG group significantly correlated with better OS (hazard Ratio [HR], 0.51; 95% confidence interval [CI], 0.27-0.95; P=0.032) than FB4 group. FB4-ATG group tended to correlate with lower NRM (HR, 0.36;95% CI, 0.13-1.06; P=0.063) than FB4 group. In comparison with FB4-TBI group, FB4-ATG group showed better OS (HR 0.52, 95% CI 0.27-0.99, P=0.049) and NRM (HR 0.034, 95% CI 0.11-0.92, P=0.034). No significant differences were observed in OS and NRM between the FB4-TBI and FB4 groups. The present study demonstrated that the FB4 plus low-dose ATG regimen improved OS and NRM, but FB4 plus low-dose TBI regimen had no clear benefit over FB4 alone, in MDS patients who used unrelated donors.

The tumor microenvironment's cells can promote or inhibit tumor formation, and there are no reports on the CD4/CD8 ratio's association with outcomes post allogeneic hematopoietic stem cell transplantation (allo-HSCT). We retrospectively evaluated the pre-transplant peripheral blood CD4/CD8 ratio in 168 patients who underwent their first allo-HSCT for hematological malignancies at our institution. When patients were divided into two groups according to the median CD4/CD8 ratio 1.35 (range, 0.09-19.89), the high CD4/CD8 ratio group had a higher incidence of relapse, equivalent non-relapse mortality and worse overall survival (OS) than the low CD4/CD8 ratio group. In a multivariate analysis, the CD4/CD8 ratio was significantly associated with an increased risk of relapse, although there was a marginally significant difference in OS. The pre-transplant peripheral blood CD4/CD8 ratio could be a novel biomarker for predicting the prognosis of allo-HSCT.

Guidelines recommend rasburicase for high-risk patients to prevent tumor lysis syndrome (TLS). However, little information is available on the incidence and outcome of TLS in AML patients. We analyzed 145 patients with AML who underwent induction therapy before the approval of rasburicase to evaluate the incidence of TLS and the necessity of rasburicase as prophylaxis. Three patients had already developed clinical TLS (CTLS) at diagnosis of AML, and another three developed CTLS after the initiation of chemotherapy. In patients without TLS at diagnosis of AML, the risk for developing TLS was classified as high in 44 patients, intermediate in 41 and low in 57, according to the current guidelines. Allopurinol alone was administered to prevent hyperuricemia in all patients. All three patients who developed CTLS after diagnosis of AML were at high risk of TLS, and had elevated serum creatinine levels and a WBC count greater than 200,000 per microliter at diagnosis of AML. Allopurinol may be insufficient to prevent TLS in high-risk patients with renal dysfunction at diagnosis of AML, especially those with a high tumor burden and a WBC count of 200,000 or more, which indicates that prophylactic administration of rasburicase should be considered.

The anti-CD38 antibody daratumumab (Dara) has been reported to improve the prognosis of multiple myeloma (MM) patients, but its use before autologous stem cell transplantation (ASCT) remains controversial. To clarify the prognostic impact of Dara before ASCT on MM, we performed a retrospective observational analysis. We analyzed 2626 patients who underwent ASCT between 2017 and 2020. In the comparison between patients not administered Dara (Dara- group) and those administered Dara (Dara+ group), the 1-year progression-free survival (PFS) rates were 87.4% and 77.3% and the 1-year overall survival (OS) rates were 96.7% and 90.0%, respectively. In multivariate analysis, age <65 years (p = 0.015), low international staging system (ISS) stage (p < 0.001), absence of unfavorable cytogenic abnormalities (p < 0.001), no Dara use before ASCT (p = 0.037), and good treatment response before ASCT (p < 0.001) were independently associated with superior PFS. In matched pair analysis, the PFS/OS of the Dara- group were also significantly superior. For MM patients who achieved complete or very good partial response (CR/VGPR) by Dara addition before ASCT, both PFS and OS significantly improved. However, in patients who did not achieve CR/VGPR before ASCT, the PFS/OS of the Dara+ group were significantly inferior to those of the Dara- group.

BACKGROUND: The number of CD34+ cells in the graft is generally associated with time to engraftment and survival in transplantation using cord blood or allogeneic peripheral blood stem cells. However, the significance of abundant CD34+ in bone marrow transplantation (BMT) remained unclear. METHODS: We retrospectively reviewed 207 consecutive adult patients who underwent their first BMT at Jichi Medical University between January 2009 and June 2021. RESULTS: The median nucleated cell count (NCC) and CD34+ cell dose were 2.17 × 108/kg (range .56-8.52) and 1.75 × 106/kg (.21-5.84), respectively. Compared with 104 patients in the low CD34+ group (below the median), 103 patients in the high CD34+ group (above the median) showed faster engraftment at day +28 in terms of neutrophil (84.6% vs. 94.2%; p =  .001), reticulocyte (51.5% vs. 79.6%; p < .001), and platelet (39.4% vs. 72.8%; p < .001). There were no significant differences in overall survival, relapse, nonrelapse mortality, acute or chronic graft-versus-host disease, or infectious complications between the two groups in univariate and multivariate analyses. Low or high NCC had no significant effect on overall survival, nonrelapse mortality, cumulative incidence of relapse and graft-versus-host disease, either. While a positive correlation was observed between NCC and the CD34+ cell dose, a high CD34+ cell dose was associated with rapid hematopoietic recovery, even in patients with NCC below the median. CONCLUSION: Measurement of CD34+ cell dose in addition to NCC was useful for predicting hematopoietic recovery, but seemed to have little influence on the long-term outcome in BMT.

Daratumumab (DARA) has become a standard care for treating patients with multiple myeloma (MM) and light chain (AL) amyloidosis. The subcutaneous (SC) administration of DARA has been demonstrated to be non-inferior to an intravenous formulation. This retrospective study evaluated patients with MM and/or AL amyloidosis who received SC DARA injections at Tochigi Medical Center Shimotsuga (TMC) and Jichi Medical University (JMU). At TMC, the first dose of DARA was administered on an outpatient basis, whereas at JMU, it was generally administered as an inpatient treatment. At TMC, nurses and pharmacists carefully explained the precautions when administering DARA 1 week in advance. DARA was administered by a physician and patients were observed for 6 h after the first dose. Consequently, outpatient DARA administration was associated with a much shorter median total chair time (345 min) than inpatient treatment (median, 7 days). The incidence of administration-related reactions was low (only one patient in each group). The results revealed that, with aggressive premedication and medical cooperation, the first dose of SC DARA can be safely administered in an outpatient setting.

BACKGROUND AIMS: This study aimed to comprehensively assess the impact of stem cell selection between bone marrow (BM) and peripheral blood (PB) in unrelated hematopoietic stem cell transplantation (HSCT) for hematological malignancies. Our objective was to identify specific factors associated with better transplant outcomes. METHODS: A retrospective analysis was conducted using data from the Japanese HSCT registry. Inclusion criteria were patients aged 0-70 years who underwent their first unrelated HSCT with BM or PB, with an 8/8 or 7/8 allele HLA match for hematological malignancies between 2010 and 2020. RESULTS: Among 10 295 patients, no significant difference was observed in overall survival, relapse, graft-versus-host disease (GVHD)-free, relapse-free survival (GRFS) or non-relapse mortality between the groups. Patients who received PB showed no clear difference in acute GVHD but had a greater rate of chronic GVHD, resulting in poor chronic GVHD-free, relapse-free survival (CRFS). Subgroup analyses highlighted the importance of patient-specific factors in source selection. Patients with non-Hodgkin lymphoma and a greater hematopoietic cell transplantation-comorbidity index showed better CRFS and GRFS when BM was the preferred source. Similar trends were observed among patients with standard-risk disease for CRFS. However, no such trends were evident among patients aged 0-24 years, indicating that both sources are viable choices for young patients. CONCLUSIONS: This real-world retrospective analysis showed similar basic outcomes for BM and PB in an unrelated setting. The results support that BM may still be preferred over PB, especially when the long-term quality of life is a major concern. A consideration of individual factors can further optimize transplant success. Further research is warranted to explore the long-term implications of stem cell source selection.

BACKGROUND: Acute myeloid leukemia (AML) is the most common indication for allogeneic hematopoietic cell transplantation (HCT). The increased availability of alternative donor sources has broadened donor types for older patients without HLA-matched sibling donors (MSD). It is uncertain if an MSD should be the first option for allogeneic HCT in patients with AML over 50 years of age. OBJECTIVE: The objective of this study was to compare survival and other posttransplant outcomes between MSDs, 8/8 allele-matched unrelated donors (MUDs), 7/8 allele-MUDs, unrelated cord blood (UCB), and haploidentical donors for patients with AML over 50 years of age. STUDY DESIGN: We conducted a retrospective study to compare outcomes in 5,704 patients with AML over 50 years of age and receiving allogeneic HCT between 2013 and 2021, using either MSD, 8/8 allele-MUD, 7/8 allele-MUD, UCB, or haploidentical donors in Japan. Complete remission (CR) and non-remission at HCT were analyzed separately for all analyses. RESULTS: In total, 3041 patients were CR, and 2663 patients were non-remission at the time of HCT. In multivariate analysis, donor type did not determine overall survival, irrespective of disease status at HCT. Leukemia-free survival (LFS) was significantly better for 8/8 allele-MUD (hazard ratio [HR], 0.77; 95% confidence interval [CI], 0.64 to 0.93; P = 0.005) and UCB (HR, 0.76; 95% CI, 0.65 to 0.88; P = 0.001), but not for 7/8 allele-MUD (HR, 0.97; 95% CI, 0.79 to 1.19; P=0.794), and haploidentical donor (HR, 0.86; 95% CI, 0.70 to 1.05; P=0.146) compared to the MSD group in non-remission status. However, donor type did not determine LFS among CR status. Relapse rates were significantly lower for 8/8 allele-MUD and UCB, whereas non-relapse mortality was higher for UCB compared to the MSD group among both CR and non-remission status. CONCLUSION: Our registry-based study demonstrated that MSDs do not lead to superior survival compared to alternative donors for patients with AML over 50 years of age. Furthermore, 8/8 allele-MUDs and UCB provide better LFS compared with MSDs during non-remission status. Therefore, MSD is not necessarily the best donor option for allogeneic HCT in this population.

BACKGROUND: Despite its promising outcome, anti-BCMA CAR-T is the most expensive myeloma treatment that has ever been developed, and its cost-effectiveness is an important issue. OBJECTIVE: This study aimed to assess the cost-effectiveness of anti-BCMA CAR-T in comparison with standard anti-myeloma therapy in RRMM patients. STUDY DESIGN: The model assumed myeloma patients in Japan and the US who have received ≥3 prior lines of anti-myeloma therapies including PIs, IMiDs, and anti-CD38 mAbs. A Markov model was constructed to compare the 'CAR-T' strategy, in which patients receive either idecabtagene vicleucel (ide-cel) or ciltacabtagene autoleucel (cilta-cel) followed by three lines of multiagent chemotherapy after relapse, to the 'no CAR-T' strategy, in which patients only receive chemotherapies. The data from the LocoMMotion, KarMMa, and CARTITUDE-1 trials were extracted. Several assumptions were made regarding long-term progression-free survival (PFS) with CAR-Ts. Extensive scenario analyses were made regarding regimens for 'no CAR-T' strategies. The outcome was an incremental cost-effectiveness ratio (ICER) with willingness-to-pay thresholds of \ 7,500,000 in Japan and $150,000 in the US. RESULTS: When a 5-year PFS of 40% with cilta-cel was assumed, the ICER of the 'CAR-T' versus 'no CAR-T' strategies was \7,603,823 in Japan and $112,191 in the US per QALY over a 10-year time horizon. When a 5-year PFS of 15% with ide-cel was assumed, the ICER was \20,388,711 in Japan and $261,678 in the US per QALY over a 10-year time horizon. The results were highly dependent on the PFS assumption with CAR-T and were robust to changes in most other parameters and scenarios. CONCLUSION: Although anti-BCMA CAR-T can be cost-effective even under current pricing, a high long-term PFS is necessary.

BACKGROUND: The early recovery of lymphocyte and monocyte cells is associated with a favorable prognosis after allogeneic stem cell transplantation (allo-HSCT); however, it is not clear whether the balance of lymphocyte and monocyte recovery affects the post-transplant prognosis. METHODS: We examined whether the time-point at which the number of lymphocytes exceeded the number of monocytes, which we termed lymphocyte-to-monocyte ratio reversal (LMRR), affected the prognosis after allo-HSCT. We retrospectively evaluated 235 patients who underwent their first allo-HSCT at our institution. RESULTS: The median number of days from HSCT to LMRR was 46 (range, 0-214), and the patients were divided into two groups according to the occurrence of LMRR by day 45 (LMRR45). In a multivariate analysis, early LMRR contributed favorably to overall survival (hazard ratio [HR] .519; 95% confidence interval [CI] .332-.812; p = .004) with fewer post-transplant relapses (HR .462; 95% CI, .274-.777; p = .004). Differences in the timing of LMRR did not affect non-relapse mortality (HR 1.477; 95% CI .779-2.80; p = .23) or the incidence of grade II-IV acute GVHD (LMRR45(+): 25.0% vs. LMRR45(-) 35.2%. p = .111). In subgroup analyses, LMRR45(+) was found to be a favorable factor for survival with less relapse, regardless of the disease risk, stem cell source, or the recovery of either lymphocyte or monocyte counts. CONCLUSIONS: An early LMRR may be a novel factor that is associated with reduced relapse and improved survival after allo-HSCT.

INTRODUCTION: Late cytomegalovirus (CMV) disease, which was defined as CMV disease occurring >100 days post-transplant, remains an important complication among allogeneic stem cell transplant recipients, even now that the prophylactic strategy using ganciclovir preemptive therapy has been established. Due to the recent expansion of donor sources and conditioning regimens, it is therefore appropriate to reevaluate the incidence, risk factors, and clinical impacts of late CMV disease. METHODS: This study included the 1295 adult patients, who underwent transplant for the first time from 2008 to 2015, without underlying disease relapse or CMV disease within 100 days post-transplant. There were no restrictions on underlying diseases or transplant procedures. RESULTS: During the median follow-up period of 48.4 months, 21 patients developed late CMV disease and the 5-year cumulative incidence of late CMV disease was 1.6%. By multivariate analysis, haploidentical related donor, adult T-cell leukemia lymphoma, and preemptive therapy before 100 days post-transplant were extracted as independent risk factors. Late CMV disease negatively affected transplant outcomes, and was identified as an independent risk factor for the non-relapse mortality rate (hazard ratio 3.83, p < 0.001) and overall survival rate (hazard ratio 4.01, p < 0.001). Although 17 of 21 patients with late CMV disease died, the main causes of death were not related to CMV, except in three patients with CMV pneumonia. CONCLUSIONS: Although the incidence of late CMV disease is low in transplant recipients, this complication negatively affects clinical courses. Therefore, transplant recipients with these risk factors should be more carefully managed.

Chronic graft-versus-host disease (cGVHD) is a multiorgan syndrome with clinical features resembling those of autoimmune diseases. Thus, understanding commonalities in the pathophysiology of cGVHD and autoimmune diseases, such as the presence of disease-risk HLA alleles, is imperative for developing novel therapies against cGVHD. Alloantibodies against H-Y antigens encoded on the Y-chromosome are well-described risk factors for cGVHD in female-to-male transplantation. However, since H-Y antigens generally localize intracellularly in the male reproductive organs, how they emerge at affected organ levels remains elusive. Here, by analyzing nationwide registry data stratified according to donor-recipient sex, we identified specific HLA class II alleles that contributed to susceptibility to male cGVHD following transplantation from HLA-identical female siblings [HLA-DRB1*15:02: hazard ratio, 1.28; 95% confidence interval, 1.03-1.58; P = 0.025]. Co-expression of HLA-DRB1*15:02 efficiently transported full-length H-Y antigens, especially DBY, to the surface. The presence of alloantibodies against DBY/HLA class II complexes significantly predicted the occurrence of cGVHD [68.8% vs. 31.7% at 1 year, P = 0.002]. Notably, the ability of HLA class II molecules to transport and present DBY to alloantibodies was closely associated with the susceptibility of HLA class II alleles to cGVHD. DBY specifically colocalized with HLA class II molecules on the dermal vascular endothelium in cGVHD and provoked complement-dependent cytotoxicity. Moreover, these complexes were observed in some male leukemic cells. Altogether, these findings suggest that vascular endothelial cells facilitate alloantibody-mediated cGVHD, and highlight that alloantibodies against DBY/HLA class II complexes could be common targets for cGVHD and a graft-versus-leukemia effect.

Abstract Allogeneic hematopoietic cell transplantation between female donors and male recipients (female-to-male allo-HCT) is a well-established risk factor for inferior survival outcomes due to a higher incidence of graft-versus-host disease (GVHD). However, a clinical significance of anti-thymocyte globulin (ATG) in the female-to-male allo-HCT has not been elucidated. In this study, we retrospectively evaluated male patients who underwent allo-HCT between 2012 and 2019 in Japan. In the female-to-male allo-HCT cohort (n = 828), the use of ATG was not associated with a decreased risk of GVHD (HR of acute GVHD 0.691 [95% CI: 0.461–1.04], P = 0.074; HR of chronic GVHD 1.06 [95% CI: 0.738–1.52], P = 0.76), but was associated with favorable overall survival (OS) and a decreased risk of non-relapse mortality (NRM) (HR of OS 0.603 [95% CI: 0.400–0.909], P = 0.016; HR of NRM 0.506 [95% CI: 0.300–0.856], P = 0.011). The use of ATG in female-to-male allo-HCT resulted in survival outcomes that were almost equivalent to those in the male-to-male allo-HCT group. Therefore, GVHD prophylaxis with ATG might overcome the inferiority of survival outcomes in female-to-male allo-HCT.

For successful chimeric antigen receptor T (CAR-T) cell therapy, CAR-T cells must be manufactured without failure caused by suboptimal expansion. In order to determine risk factors for CAR-T cell manufacturing failure, we performed a nationwide cohort study in Japan and analysed patients with diffuse large B-cell lymphoma (DLBCL) who underwent tisagenlecleucel production. We compared clinical factors between 30 cases that failed (7.4%) with those that succeeded (n = 378). Among the failures, the proportion of patients previously treated with bendamustine (43.3% vs. 14.8%; p < 0.001) was significantly higher, and their platelet counts (12.0 vs. 17.0 × 104 /μL; p = 0.01) and CD4/CD8 T-cell ratio (0.30 vs. 0.56; p < 0.01) in peripheral blood at apheresis were significantly lower than in the successful group. Multivariate analysis revealed that repeated bendamustine use with short washout periods prior to apheresis (odds ratio [OR], 5.52; p = 0.013 for ≥6 cycles with washout period of 3-24 months; OR, 57.09; p = 0.005 for ≥3 cycles with washout period of <3 months), low platelet counts (OR, 0.495 per 105 /μL; p = 0.022) or low CD4/CD8 ratios (<one third) (OR, 3.249; p = 0.011) in peripheral blood at apheresis increased the risk of manufacturing failure. Manufacturing failure remains an obstacle to CAR-T cell therapy for DLBCL patients. Avoiding risk factors, such as repeated bendamustine administration without sufficient washout, and risk-adapted strategies may help to optimize CAR-T cell therapy for DLBCL patients.

The prognosis of multiple myeloma (MM) has dramatically improved with the development of new drugs, and it has become important to determine the appropriate combinations of these novel agents. This study was a systematic review and network meta-analysis (NMA) of randomized trials in patients with relapsed and/or refractory (RR) MM. The PubMed, Cochrane, and Embase databases were searched for randomized trials from 1 January 2002 to 28 February 2022 of patients treated for MM. The primary end-point was progression-free survival (PFS), evaluated as a hazard ratio (HR) with a 95% confidence interval (95% CI) compared to dexamethasone (DEX). The p-score was used to rank treatments. Of a total of 1136 abstracts screened, 37 studies were selected, including 34 treatment options for RRMM. Daratumumab, lenalidomide and DEX was found to be the best treatment for RRMM, with the best HR compared to DEX (HR, 0.13; 95% CI, 0.08-0.20; p-score 0.9796). There was no evidence of significant heterogeneity (I2 , 41.3%; p = 0.146). The current NMA confirmed the excellent efficacy of three-drug regimens including anti-CD38 antibodies to treat RRMM and provides background data to evaluate the efficacy of chimeric antigen receptor T-cell treatments and bispecific T-cell engager therapies.

Tumor lysis syndrome (TLS) is a metabolic disorder caused by massive tumor lysis. Hypouricemic agents are administered to prevent TLS-related hyperuricemia and renal failure. We experienced three cases of urine xanthine crystals during TLS in patients with hematologic malignancies who received prophylactic febuxostat. Yellowish and pinkish deposits were observed in urinary tract catheters and urinary bags. Urine microscopy revealed that the deposits were xanthine crystals. In rapid tumor lysis, inhibition of xanthine oxidase can cause xanthine accumulation and urine xanthine crystallization. During TLS, urine xanthine crystals may be overlooked, so careful observation and management are required to avoid xanthine nephropathy.

Cardiotoxicity after allogeneic stem cell transplantation (SCT) is associated with a high rate of mortality and worsening quality of life. The relation between daunorubicin dose and post- allogeneic stem cell transplantation (SCT) cardiotoxicity remains unclear. We retrospectively evaluated 171 patients with acute myeloid leukemia (AML) who underwent their first allogeneic SCT at our institution between 2005 and 2021. High-dose daunorubicin (50 mg/m2/day for 5 days) and cytarabine were usually used as induction therapy for AML. The median cumulative daunorubicin dose was 310 mg/m2 (range, 0-950 mg/m2), and 43 patients received two courses of induction therapy with high-dose daunorubicin (daunorubicin doses of ≥500 mg/m2). Cardiotoxicity developed in 12 patients, and the cumulative incidence at 2 years after SCT was 7.1%. Univariable analysis revealed that female sex, left ventricular ejection fraction (LVEF) of < 60% before SCT, and daunorubicin doses of ≥ 500 mg/m2 were associated with cardiotoxicity. Multivariable analysis showed that a daunorubicin dose of ≥ 500 mg/m2 was an independent risk factor for cardiotoxicity. LVEF decline during the study was observed with an increase in the daunorubicin dose, and only a daunorubicin dose of ≥ 500 mg/m2 was associated with a pre-SCT decreased LVEF. Second induction therapy with high-dose daunorubicin is a risk factor for cardiotoxicity after SCT. This should be taken into consideration when determining reinduction therapies for SCT-eligible patients with relapsed or refractory AML.

症例は63歳男性．非小細胞肺癌と診断され，2次治療としてニボルマブの単独投与が行われた．治療68日目，肺障害によりニボルマブは中止となった．治療111日目から皮疹，肝機能障害，肺障害を認め，ステロイドの全身投与が開始された．治療115日目，急な貧血の進行を認め輸血依頼があった．不規則抗体検査と直接抗グロブリン試験は陽性を示した．抗体解離試験にて自己抗体の特異性なし，ZZAP処理法にて血液型はB型，RhD陽性（CcDee），同種抗体なしと判定した．自己免疫性溶血性貧血（AIHA）と診断され，交差適合試験で凝集反応の弱いE抗原陰性赤血球製剤計12単位の輸血が行われた．ステロイドパルス療法が奏功し徐々に貧血の改善を認めた．免疫関連有害事象としてのAIHAは重篤となり輸血を必要とする場合が想定され，迅速に血液型判定や反応の少ない赤血球製剤の確保等の対応が必要と考えられる．