Impaired humoral immunity following COVID-19 vaccination in HTLV-1 carriers.

BACKGROUND: Whether human T-lymphotropic virus type 1 (HTLV-1) carriers can develop sufficient humoral immunity after coronavirus disease 2019 (COVID-19) vaccination is unknown. METHODS: To investigate humoral immunity after COVID-19 vaccination in HTLV-1 carriers, a multicenter, prospective observational cohort study was conducted at five institutions in southwestern Japan, an endemic area for HTLV-1. HTLV-1 carriers and HTLV-1-negative controls were enrolled for this study from January to December 2022. During this period, the third dose of the COVID-19 vaccine was actively administered. HTLV-1 carriers were enrolled during outpatient visits, while HTLV-1-negative controls included health care workers and patients treated by participating institutions for diabetes, hypertension, or dyslipidemia. The main outcome was the effect of HTLV-1 infection on the plasma anti-COVID-19 spike IgG (IgG-S) titers after the third dose, assessed by multivariate linear regression with other clinical factors. RESULTS: We analyzed 181 cases (90 HTLV-1 carriers, 91 HTLV-1-negative controls) after receiving the third dose. HTLV-1 carriers were older (median age 67.0 vs. 45.0 years, p < 0.001) and more frequently had diabetes, hypertension, or dyslipidemia than did HTLV-1-negative controls (60.0% vs. 27.5%, p < 0.001). After the third dose, the IgG-S titers decreased over time in both carriers and controls. Multivariate linear regression in the entire cohort showed that time since the third dose, age, and HTLV-1 infection negatively influenced IgG-S titers. After adjusting for confounders such as age, or presence of diabetes, hypertension, or dyslipidemia between carriers and controls using the overlap weighting propensity score method, and performing weighted regression analysis in the entire cohort, both time since the third dose and HTLV-1 infection negatively influenced IgG-S titers. CONCLUSIONS: The humoral immunity after the third vaccination dose is impaired in HTLV-1 carriers; thus, customized vaccination schedules may be necessary for them.

IKZF1plus alterations are not associated with outcomes in Philadelphia-positive acute lymphoblastic leukemia patients enrolled in the FBMTG ALL/MRD2008 trial.

OBJECTIVE: The prognostic significance of IKZF1plus in adult Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL) patients had remained to be clarified. METHODS: We conducted a prospective, multicenter study, the ALL/MRD2008 trial, and investigated the clinical significance of IKZF1plus . RESULTS: From December 2008 to November 2013, 38 untreated Ph+ ALL patients were enrolled. At the end of the induction, 97.4% of patients (37/38) achieved complete hematological remission, with MRD-negativity of 48.6% (18/37). There were 19 patients with IKZF1plus , 13 with IKZF1 deletion alone (ΔIKZF1) and 4 with no IKZF1 deletions (no ΔIKZF1). The probability of 3-year DFS and OS in these Ph+ ALL patients were 50% (95% confidence interval [CI], 33-65) and 55% (95% CI, 38-69), respectively. There was no significant difference between IKZF1plus , ΔIKZF1, and no ΔIKZF1 in DFS (47%, 54%, 75% [p = .63]) or OS (47%, 62%, NA [p = .39]). CONCLUSIONS: We revealed no relationship between IKZF1plus status and survival outcomes in Ph+ ALL patients treated with imatinib/dasatinib combination chemotherapy. Further investigations are warranted to clarify the prognostic significance of IKZF1plus in adult Ph+ ALL patients.

Identification of putative noncanonical driver mutations in patients with essential thrombocythemia.

Essential thrombocythemia (ET) cases without canonical JAK2, CALR, or MPL mutations, that is, triple-negative (TN) ET, have been found in 10%-20% of ET cases. Owing to the limited number of TN ET cases, its clinical significance remains unclear. This study evaluated TN ET's clinical characteristics and identified novel driver mutations. Among 119 patients with ET, 20 (16.8%) had no canonical JAK2/CALR/MPL mutations. Patients with TN ET tended to be younger and had lower white blood cell counts and lactate dehydrogenase values. We identified putative driver mutations in 7 (35%): MPL S204P, MPL L265F, JAK2 R683G, and JAK2 T875N were previously reported as candidate driver mutations in ET. Moreover, we identified a THPO splicing site mutation, MPL*636Wext*12, and MPL E237K. Four of the seven identified driver mutations were germline. Functional studies on MPL*636Wext*12 and MPL E237K revealed that they are gain-of-function mutants that increase MPL signaling and confer thrombopoietin hypersensitivity with very low efficiency. Patients with TN ET tended to be younger, although this was thought to be due to the inclusion of germline mutations, hereditary thrombocytosis. Accumulating the genetic and clinical characteristics of noncanonical mutations may help future clinical interventions in TN ET and hereditary thrombocytosis.

Predictors of impaired antibody response after SARS-CoV-2 mRNA vaccination in hematopoietic cell transplant recipients: A Japanese multicenter observational study.

HCT recipients reportedly have a high mortality rate after developing COVID-19. SARS-CoV-2 vaccination is generally useful to prevent COVID-19. However, its safety and efficacy among HCT recipients remain elusive. This large-scale prospective observational study including 543 HCT recipients with 37-months interval from transplant demonstrated high safety profiles of mRNA vaccine: only 0.9% of patients avoided the second dose due to adverse event or GVHD aggravation following the first dose. Regarding the efficacy, serological response with a clinically relevant titer (≥250 BAU/mL) was obtained in 397 (73.1%) patients. We classified the remaining 146 patients as impaired responders and compared the clinical and immunological parameters between two groups. In allogeneic HCT recipients, multivariable analysis revealed the risk factors for impaired serological response as follows: age (≥60, 1 points), HLA-mismatched donor (1 points), use of systemic steroids (1 points), absolute lymphocyte counts (<1000/µL, 1 points), absolute B-cell counts (<100/µL, 1 points), and serum IgG level (<500 mg/dL, 2 points). Notably, the incidence of impaired serological response increased along with the risk scores: patients with 0, 1-3, and 4-7 points were 3.9%, 21.8%, and 74.6%, respectively. In autologous HCT recipients, a shorter interval from transplant to vaccination was the only risk factor for impaired serological response. Our findings indicate that two doses of SARS-CoV-2 vaccine are safe but insufficient for a part of HCT recipients with higher risk scores. To improve this situation, we should consider additional treatment options, including booster vaccination and prophylactic neutralizing antibodies during the SARS-CoV-2 pandemic.

Outcome predictors after retransplantation in relapsed acute lymphoblastic leukemia: a multicenter, retrospective study.

Retransplantation is the only curative treatment option for patients with acute lymphoblastic leukemia (ALL) that has relapsed after allogeneic hematopoietic cell transplantation (allo-HCT); however, data in this setting remain scant. Hence, this multicenter, retrospective study aims to determine outcome predictors after retransplantation in relapsed ALL. We examined 55 recipients who underwent multiple allo-HCTs during 2006-2018. The 2-year overall survival (OS), progression-free survival (PFS), and non-relapse mortality rates were 35.9%, 29.1%, and 23.6%, respectively. We observed a trend of better outcome in Ph + ALL (n = 22) patients compared with non-Ph ALL (n = 33) patients; the 2-year PFS was 40.9% versus 21.2%, indicating a beneficial effect of more potent second- or third-generation tyrosine kinase inhibitors. Univariate analysis revealed that late relapse after the previous transplant was the only significant predictor of better transplant outcome among Ph + ALL patients, whereas factors related to prolonged OS/PFS in non-Ph ALL patients were late relapse after the previous transplant, longer duration from disease relapse/progression to second or more allo-HCT, disease status at the transplantation, and good performance status. Nevertheless, further investigations are warranted to determine whether novel molecular-targeted agents with higher efficacy and fewer toxicities could exceed conventional chemotherapies as a bridging strategy to next allo-HCT and improve the outcomes of non-Ph ALL patients.

Outcomes of Allogeneic Hematopoietic Stem Cell Transplantation for ATL with HTLV-1 Antibody-Positive Donors.

Allogeneic hematopoietic stem cell transplantation (allo-HCT) is the only available curative treatment option for patients with aggressive adult T cell leukemia-lymphoma (ATL). Donor human T cell leukemia virus (HTLV) 1 seropositivity is a critical concern when choosing relative donors, as they are not usually recommended due solely to the occurrence of donor-derived ATL. A previous report suggested that allo-HCT with an HTLV-1-seropositive donor increased ATL-related mortality. We updated the risk assessment for choosing an HTLV-1-seropositive allo-HCT donor for ATL. Our current registry data, which include larger numbers of HTLV-1-seropositive donors and longer observation periods, revealed no significant difference in overall survival (hazard ratio [HR], 0.93; 95% confidence interval [CI], 0.70-1.24; P = .61) or cumulative incidence of either ATL-related (HR, 0.96; 95% CI, 0.64 to 1.45; P = .80) or non-ATL-related mortality (HR, 0.91; 95% CI, 0.61 to 1.37; P = .66). Similarly, when considering only patients with ATL in complete remission, there was no significant difference in overall survival (HR, 1.02; 95% CI, 0.70 to 1.49; P = .91) or cumulative incidence of either ATL-related (HR, 1.20; 95% CI, 0.66 to 2.20; P=0.54) or non-ATL-related mortality (HR, 0.86; 95% CI, 0.52-1.42; P = .66). These data indicate that selecting HTLV-1-seropositive donors might not be contraindicated for patients with ATL receiving allo-HCT if alternative donors are unavailable. Further risk assessment remains to be performed.

Safety and Seropositivity after Live Attenuated Vaccine in Adult Patients Receiving Hematopoietic Stem Cell Transplantation.

Vaccination against vaccine-preventable diseases (VPDs) is highly recommended for hematopoietic stem cell transplantation (HSCT) recipients by several guidelines; however, the safety and seropositivity after live attenuated vaccines remain unclear in adult HSCT recipients. We analyzed titers of antibodies against measles, rubella, mumps, and varicella zoster virus (VZV) from Japanese adult patients who underwent allogeneic HSCT (allo-HSCT) (n = 74), autologous HSCT (auto-HSCT) (n = 39), or chemotherapy (n = 93). The seropositive rates for measles, rubella, mumps, and VZV in allo-HSCT recipients were 20.2%, 36.4%, 5.4%, and 55.4%, respectively. These rates were equivalent to those in auto-HSCT recipients but were significantly lower than those in patients receiving chemotherapy. Antibody titers tended to gradually decrease with time. Twenty-nine allo-HSCT recipients and 8 auto-HSCT recipients received live attenuated vaccines against VPDs for which they tested seronegative. The titers of antibodies against measles, rubella, and mumps significantly increased after 2 shots of vaccine, and the seropositive rate increased up to 19%, 30%, and 27%, respectively. Three patients (8.1%) experienced mild adverse events, which resolved promptly, indicating safe administration of the live attenuated vaccines. In multivariate analysis, history of chronic graft-versus-host disease was significantly associated with high seropositivity for measles as well as high seroconversion rate for measles after vaccination. Live attenuated vaccines against VPDs were safely administered in seronegative adult HSCT recipients. A further observational study is crucial to evaluate the efficacy of vaccination in seronegative HSCT patients.

Quantitation of hematogones at the time of engraftment is a useful prognostic indicator in allogeneic hematopoietic stem cell transplantation.

UNLABELLED: Transient marrow expansion of normal B-cell precursors, termed hematogones, is occasionally observed after hematopoietic stem cell transplantation (HSCT). To understand the clinical significance of this phenomenon, we enumerated hematogones in 108 consecutive patients who received allogeneic HSCT for the treatment of hematologic malignancies, including acute myelogenous leukemia, advanced myelodysplastic syndromes, acute lymphoblastic leukemia, and non-Hodgkin lymphoma. Hematogone quantitation was performed at the time of complete donor engraftment (median day 25 and 32 in patients who received bone marrow and cord blood cell transplants, respectively). Hematogones were polyclonal B cells, and their frequencies correlated positively with blood B-cell numbers, and inversely with donors' but not recipients' age, suggesting that hematogones reflect cell-intrinsic B-cell potential of donor cells. Interestingly, patients developing hematogones that comprised > 5% of bone marrow mononuclear cells constituted a group with significantly prolonged overall survival and relapse-free survival, irrespective of their primary disease or donor cell source. In addition, patients with > 5% hematogones developed severe acute graft-versus-host diseases less frequently, which may contribute toward their improved survival. We therefore conclude that the amount of hematogones at the time of engraftment may be a useful tool in predicting the prognosis of patients treated with allogeneic HSCT. KEY POINTS: Quantitation of hematogones at engraftment is useful to predict prognosis of patients treated with allogeneic stem cell transplantation.

Epstein-Barr virus-positive diffuse large B-cell primary central nervous system lymphoma associated with organized chronic subdural hematoma: a case report and review of the literature.

We here report on a rare case of Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL) detected in both brain parenchyma and in an organized chronic subdural hematoma (OCSH). A 96-year-old man diagnosed with asymptomatic OCSH in the left frontal convexity was referred to our hospital because of a de novo mass lesion just beneath the OCSH on contrast-enhanced magnetic resonance imaging. The size of the OCSH remained stable. We diagnosed the lesion as a malignant tumor. At surgery, the organized hematoma and the soft fragile tumor were removed. Histological examinations revealed pleomorphic lymphoid cells not only in the brain tissue but also in the OCSH component with tumor necrosis, and these were immunopositive for B-cell markers. In situ hybridization revealed positive signals for EBV-encoded small RNAs, consistent with EBV-positive DLBCL. Since the membranes of the subdural hematoma were fibrous and the tumor progression resulted in necrosis of the tumor, the DLBCL may have originally developed in the OCSH and infiltrated into the brain parenchyma. We believe that this rare case provides crucial information for the understanding of DLBCLs associated with OCSH.

Higher incidence of injection site reactions after subcutaneous bortezomib administration on the thigh compared with the abdomen.

Subcutaneous (sc) rather than intravenous administration of bortezomib (Bor) is becoming more common for treating multiple myeloma (MM) because scBor results in lower incidence and severity of peripheral neuropathy and has equivalent efficacy. Bor is an irritant cytotoxic agent when it leaks out; therefore, it is recommended that injections of scBor should be rotated among eight different sites on the abdomen and thigh. However, detailed information about injection site reaction (ISR) has not been sufficiently documented. We retrospectively analyzed the incidence and severity of ISR following scBor administration in 15 Japanese patients with MM. Grade 1 ISR occurred following 40 of 158 (25.3%) scBor injections in ten patients, whereas grade 2 ISRs occurred following seven injections (4.4%) in five patients. Five patients did not develop ISR. Of note, grade 2 ISR was documented in 6 of 65 (9.2%) thigh injections but only in 1 of 93 (1.1%) abdominal injections. These data show that grade 2 ISRs were more common in the thigh compared with the abdomen possibly because the thigh contains lesser adipose tissue than the abdomen. Grade 2 ISRs resolved without any sequela within a median of 7 d. scBor administration on the abdomen instead of the thigh should be considered, especially for emaciated patients, because ISR rapidly resolves within the interval before the next injection even if it occurs.

A decrease in newly diagnosed patients with adult T-cell leukemia/lymphoma in Kagoshima, a highly endemic area of HTLV-1 in southwestern Japan.

Adult T-cell leukemia/lymphoma (ATL) is a peripheral T-cell malignancy caused by human T-cell leukemia virus type-I (HTLV-1). This study investigated whether the number of newly diagnosed patients with ATL is decreasing in the background of a declining number of individuals infected by HTLV-1 in Kagoshima, Japan, one of the most endemic areas of HTLV-1 in the world. We retrospectively analyzed the number of newly diagnosed patients with ATL between January 2001 and December 2021 in three major hospitals. The number of newly diagnosed patients with B-cell non-Hodgkin lymphoma (B-NHL) in the same period was examined as an internal control. One thousand eighteen and 2,029 patients with ATL and B-NHL were registered, respectively. The age-adjusted incidence of ATL steadily increased between 2001 and 2012, whereas that between 2013 and 2021 decreased. Despite the limitation of its retrospective nature, this is the first report indicating a decrease in ATL patients in Japan.

Impact of a third dose of anti-SARS-CoV-2 vaccine in hematopoietic cell transplant recipients: A Japanese multicenter observational study.

This prospective observational study aimed to assess the serological response and safety after the third booster shot of SARS-CoV-2 mRNA vaccines in 292 hematopoietic cell transplant (HCT) recipients. In our patients, mild systemic reactions were present in 10-40% and GVHD aggravation in 1.1%. Overall, clinically relevant response (>250 U/mL) was observed in 93.1% of allogeneic (allo)-HCT recipients and 70.6% of autologous (auto)-HCT recipients, respectively. Of note, detectable antibody response with any titer following the first two doses was a powerful predictor for adequate response after booster shot in both cohorts. For such patients, 98.8% of allo- and 92.3% of auto-HCT recipients obtained clinically relevant response after dose 3. In addition, continued systemic steroid and/or calcineurin inhibitors at the booster shot significantly correlated with serological response. These findings highlighted that booster vaccination efficiently improved serological response without safety concerns and thus recommended for the majority of HCT recipients.

Clinical features and outcome of X-linked lymphoproliferative syndrome type 1 (SAP deficiency) in Japan identified by the combination of flow cytometric assay and genetic analysis.

OBJECTIVE: X-linked lymphoproliferative syndrome (XLP) type 1 is a rare immunodeficiency, which is caused by mutations in SH2D1A gene. The prognosis of XLP is very poor, and hematopoietic stem cell transplantation (HSCT) is the only curative therapy. We characterized the clinical features and outcome of Japanese patients with XLP-1. METHODS: We used a combination of flow cytometric analysis and genetic analysis to identify XLP-1 and reviewed the patient characteristics and survival with HSCT. RESULTS: We identified 33 patients from 21 families with XLP-1 in Japan. Twenty-one of the patients (65%) who did not undergo a transplant died of the disease and complications. Twelve patients underwent HSCT, and 11 of these (92%) survived. CONCLUSION: We described the clinical characteristics and outcomes of Japanese patients with XLP-1, and HSCT was the only curative therapy for XLP-1. The rapid and accurate diagnosis of XLP with the combination of flow cytometric assay and genetic analysis is important.

Fatal candidemia caused by azole-resistant Candida tropicalis in patients with hematological malignancies.

Candida tropicalis is one of the most important Candida species causative of candidemia that is isolated from the blood of patients with hematological malignancies. Candidemia caused by C. tropicalis is known to be highly virulent in neutropenic patients. C. tropicalis has been shown to be favorably sensitive to azole agents in general. Here we discuss 5 cases of candidemia caused by C. tropicalis in patients with hematological malignancies in our unit, and we note that 4 isolates were resistant to azole agents, including fluconazole, itraconazole, and voriconazole. In addition, 2 patients developed breakthrough candidemia caused by C. tropicalis while receiving prophylaxis with azole agents. Interestingly, 2 of the 4 patients with azole-resistant C. tropicalis isolates had never received any antifungal drugs. We also examined the susceptibilities of C. tropicalis to antifungal agents, using 39 non-blood isolates detected from 2003 to 2009. Around 40 % of the isolates were resistant to azole agents, and all of them were highly sensitive to amphotericin B and micafungin. The resistance to azoles was not associated with previous exposure to those agents. In our unit, 2 of the 4 cases of candidemia caused by azole-resistant C. tropicalis resulted in a poor prognosis. These findings suggested that empirical therapeutic strategies for candidemia should be modified based on the local antifungal resistance pattern.

[Clinical outcomes of allogeneic hematopoietic stem cell transplantation for adult primary myelofibrosis: retrospective analysis by Fukuoka BMT group].

We retrospectively analyzed outcomes of eight evaluable patients with primary myelofibrosis (PMF) who received allogeneic hematopoietic stem cell transplantation (allo-HSCT), using different graft sources; four patients received peripheral blood stem cells, three bone marrow, and one umbilical cord blood. The median age was 48 years (range, 43~64 years). Seven patients had an intermediate or high Dupriez score. Three patients underwent myeloablative conditioning, whereas five underwent reduced-intensity conditioning regimens. Engraftment was obtained in all of these recipients. The median days to reach a neutrophil count above 0.5×10(9)/l and platelet count above 20×10(9)/l were 20 and 35 days, respectively. No treatment-related deaths were observed within 100 days after allo-HSCT. Two patients died of sepsis or late-onset non-infectious pulmonary complications. Four patients developed grade I to II acute GVHD, and six patients developed chronic GVHD. The estimated 3-year overall survival was 75% with a median follow up time of 43 months (range, 6~127). Four of 5 patients who were transfusion-dependent became free from transfusion after allo-HSCT. In six of seven patients, a regression of fibrosis was confirmed by bone marrow biopsy. Despite the small number of cases, our results suggested that allo-HSCT is an encouraging curative strategy for treating PMF.

Bisphosphonate Use for Glucocorticoid-Induced Osteoporosis in Elderly Patients with Immune Thrombocytopenia Receiving Prolonged Steroid Therapy: A Single Institute Retrospective Study.

Prednisolone, used as a standard initial treatment for immune thrombocytopenia (ITP), is an important risk factor for osteoporosis. To investigate the prevention of glucocorticoid-induced osteoporosis (GIO) in elderly ITP patients receiving prolonged steroid therapy, associations between GIO prevention and the real-world data of score changes of a dual-energy X-ray absorptiometry (DXA) scan, FRAX® and the Garvan tool during the initial loading of prednisolone were examined. In our institute, 22 ITP patients aged ≥ 70 years received 0.5−1.0 mg/kg prednisolone for 2−3 weeks as the initial ITP treatment between 2014 and 2021. The femoral neck bone mineral density (BMD) measured by DXA scan was entered into FRAX® to define the risk-adapted approach to bisphosphonate during the initial loading of prednisolone. Bisphosphonate was administered according to <−1.0 femoral neck BMD T-score measured by DXA scan. Worse scores of FRAX® and the Garvan tool were associated with bisphosphonate use for short-term fracture prevention in primary GIO; however, there were no incidents of fracture or significant differences in probabilities determined by FRAX® and the Garvan tool. During the initial loading of prednisolone, prescribing bisphosphonate might prevent the reduction in BMD in elderly patients with ITP receiving prolonged steroid therapy.

A phase I/II study of 10-min dosing of bendamustine hydrochloride (rapid infusion formulation) in patients with previously untreated indolent B-cell non-Hodgkin lymphoma, mantle cell lymphoma, or relapsed/refractory diffuse large B-cell lymphoma in Japan.

PURPOSE: This phase I/II clinical study was conducted to examine the safety, tolerability, pharmacokinetics, and efficacy of 10-min dosing of bendamustine in patients with previously untreated indolent B-cell non-Hodgkin lymphoma (iNHL) or mantle cell lymphoma (MCL) (Group 1) and patients with relapsed/refractory diffuse large B-cell lymphoma (rrDLBCL) (Group 2). METHODS: Rituximab 375 mg/m2 was administered intravenously every 28 days to Group 1 patients on day 1 and every 21 days to Group 2 patients on day 1. Bendamustine 90 mg/m2/day was administered to the former on days 1 and 2; bendamustine 120 mg/m2/day was administered to the latter on days 2 and 3. Each regimen was delivered up to six cycles for both groups. The primary endpoints were safety and tolerability in Groups 1 and 2, respectively. RESULTS: Among 37 enrolled patients, safety was assessed in 36. In Group 1 (n = 30), 27 patients (90%) had follicular lymphoma. Adverse events (AEs) were observed in all 30 patients in Group 1. Dose-limiting toxicities were observed in two of six patients in Group 2. Common AEs included lymphocyte count decreased (86.7%, 100%). In Group 1, overall response and complete response rates were 93.1% (95% confidence interval [CI] 77.2-99.2%) and 75.9% (95% CI 56.5-89.7%), respectively. The Cmax and AUC of bendamustine tended to be higher in Group 2 than in Group 1. CONCLUSIONS: This study showed that bendamustine is safe, well-tolerated and effective for patients with previously untreated iNHL, MCL or rrDLBCL. Pharmacokinetic data were equivalent to those obtained outside of Japan. REGISTRATION NUMBERS: Registration NCT03900377; registered April 3, 2019.

Cord blood transplantation with a reduced-intensity conditioning regimen using fludarabine and melphalan for adult T-cell leukemia/lymphoma.

Adult T-cell leukemia/lymphoma (ATLL) is a peripheral T-cell lymphoma with a poor prognosis when treated with chemotherapy alone; therefore, allogeneic stem cell transplantation is a consideration. We attempted cord blood transplantation (CBT) using a reduced-intensity conditioning regimen without total body irradiation (non-TBI-RIC) to allow for the best possible timing of transplantation and improve survival outcomes, particularly in older patients. Forty-eight patients (27 male, 21 female) underwent CBT using fludarabine (Flu) 125 mg/m2 and melphalan (Mel) 140 mg/m2 as pre-transplant conditioning. The median age was 32 years (range 44-72), and 21 patients were in complete remission (CR) at the time of CBT. The median duration to neutrophil engraftment (NE) was 19.5 days (range 15-50), with a cumulative incidence of NE of 86.7% at day 50 after CBT. The 1- and 3-year overall survival (OS) rates were 40.4% and 37.7%, respectively. The 3-year OS rate in CR patients was 60.8%, compared with 18.8% in non-CR patients. In ATLL patients, CBT with non-TBI-RIC using Flu/Mel is a promising treatment strategy.

Clinical features and chromosomal/genetic aberration in adult acute lymphoblastic leukemia in Japan: results of Fukuoka Blood & Marrow Transplant Group Studies ALL MRD 2002 and 2008.

Acute lymphoblastic leukemia (ALL) is a common neoplasm in children, but less frequent in adults. Since information on clinical features and genetics of adult ALL in Japan is limited, we analyzed 215 subjects aged 16-65 years with untreated ALL enrolled in the Fukuoka Blood & Marrow Transplant Group studies ALL MRD 2002 and 2008. The prevalence of ALL was bimodal, with the larger group aged 56-65 years. Immunophenotypic characterization showed B-lineage is more frequent than T-lineage ALL (78.6 vs 13.0%), with age-related differences. The proportion with BCR-ABL1 rearrangement increased progressively with age, up to 55.7% among subjects aged over 56-65 years. Rearrangements involving the KMT2A gene, ETV6-RUNX1, and TCF3-PBX1 were rare in this study cohort. The overall incidence of hyperdiploidy was only 1.7%, and there were no cases with hypodiploidy. Overall survival varied by age and cytogenetics. Older subjects and those with BCR-ABL1 tended to have inferior outcomes. In this epidemiological study of Japanese adult ALL, the majority of subjects had B-lineage ALL, the T-cell phenotype was most frequent in those aged 16-25, and BCR-ABL1 rearrangement was very common, with prevalence increasing with age. These types of adult ALL are potentially manageable with targeted therapies.

Efficacy of prophylactic letermovir for cytomegalovirus reactivation in hematopoietic cell transplantation: a multicenter real-world data.

A novel anti-cytomegalovirus (CMV) agent, letermovir (LMV), could reportedly improve the outcomes of allogeneic hematopoietic cell transplantation (allo-HCT) recipients because of its high potential to prevent CMV reactivation. Therefore, 685 Japanese allo-HCT recipients, of whom ~80% had a high risk of CMV reactivation, were retrospectively analyzed to assess the impacts of prophylactic LMV on the incidence of clinically significant CMV (csCMV) infection as well as their transplant outcome. By comparing 114 patients who received LMV prophylaxis for a median 92 days to 571 patients without prophylaxis, we observed that prophylactic LMV could significantly (1) reduce the 180-day cumulative incidence of csCMV infection (44.7 vs. 72.4%, p < 0.001), (2) delay the median time until initiation of CMV antigenemia-guided preemptive therapy (90 vs. 36 days, p < 0.001), (3) shorten the duration of anti-CMV preemptive treatment (21 vs. 25 days, p = 0.006), and (4) improve the overall survival rate at 180 days after transplant (80.4 vs. 73.0%, p = 0.033) with a trend of lower non-relapse mortality (8.9 vs. 14.9%, p = 0.052). Our findings demonstrate that prophylactic LMV treatment is highly effective in preventing the development of csCMV infection and ultimately reduces transplant-related mortality.