Successful Pregnancy and Delivery After Frozen-thawed Embryo Transfer Following the Third Discontinuation of Tyrosine Kinase Inhibitor in a Woman with Chronic Myeloid Leukemia.

Assisted reproductive technology is a viable option for pregnant women with chronic myeloid leukemia. We herein report the case of a patient who underwent successful fertility treatment with frozen embryo preservation at 36 years of age, followed by embryo transfer at 39 years of age, thus resulting in pregnancy and delivery after a third discontinuation of tyrosine kinase inhibitors (TKI). Despite the difficulty of long-term TKI withdrawal, the patient's strong desire for a baby led to a successful pregnancy and delivery with no apparent deformities or abnormalities. Thus, our case highlights the importance of collaboration between reproductive medicine physicians and hematologists.

Investigation of biomarkers to predict outcomes in allogeneic hematopoietic stem cell transplantation.

BACKGROUND: Various biomarkers have been developed and evaluated to predict the prognosis and complications of allogeneic hematopoietic cell transplantation (HCT). Most previous studies conducted on different biomarkers evaluated single effects such as those associated with inflammation, immunology, iron metabolism, and nutrition, and only a few studies have comprehensively analyzed markers. OBJECTIVE: The study aimed to survey comprehensive multiple markers prior to HCT and extract those that significantly predict the outcomes. STUDY DESIGN: A prospective multicenter observational study was performed. (UMIN000013506) Patients undergoing HCT for hematologic diseases were consecutively enrolled. Besides the usual clinical biomarkers, serum samples for extra-clinical biomarkers were collected and cryopreserved before starting the conditioning regimen. A total of 32 candidate biomarkers were selected, 23 from hematology, biochemistry, immunology, nutrition, and iron metabolism, and 9 from composite markers. Based on the area under the curve (AUC) values for survival, promising biomarkers was extracted. Internal validation for these markers was applied based on bootstrap methods. Setting the cut-off values for them, log-rank test was applied and outcomes including overall survival (OS), relapse, and non-relapse mortality (NRM) were evaluated using multivariate analyses. Furthermore, detailed analysis including transplant-related complications and external validation were conducted focusing on C-reactive protein (CRP) to platelet (Plt) ratio. RESULTS: A total of 152 patients with hematologic malignancies were enrolled from April 2014 to March 2017. CRP, soluble interleukin-2 receptor (IL2R), CRP to albumin (Alb) ratio, CRP to Plt ratio, Plt to IL2R ratio, and IL2R to Alb ratio were identified as promising markers. Internal validation successfully confirmed their reliability of AUC and multivariate analysis demonstrated the statistical significance between the higher and the lower markers. Above all, a higher CRP to Plt ratio was significantly associated with a lower OS (hazard ratio [HR] 2.77; 95% confidence interval [CI] 1.30-5.91; P = 0.008) and higher non-relapse mortality rates (HR 2.79; 95%CI 1.14-6.80; P = 0.024) at 180 days. Furthermore, univariate analysis showed that a higher CRP to Plt ratio was significantly associated with a higher incidence of sinusoidal obstructive syndrome (P < 0.001) and bloodstream infection (P = 0.027). An external validation test confirmed the significance of the CRP to Plt ratio for these outcomes. CONCLUSION: The multicenter prospective observational study successfully identified significant biomarkers in patients with hematologic malignancies who received HCT. In particular, CRP to Plt ratio was identified as a novel and useful biomarker for predicting transplant outcomes. Further investigations are needed to validate the novel markers, analysis of the pathophysiology, and application to treatment settings other than HCT.

Differential clinical impact of letermovir prophylaxis according to graft sources: a KSGCT multicenter retrospective analysis.

ABSTRACT: Clinically significant cytomegalovirus infection (csCMVi) is frequently observed after allogeneic hematopoietic stem cell transplantation (HSCT) and prophylaxis with letermovir is commonly adopted. However, the clinical benefit of letermovir prophylaxis according to graft sources has not been sufficiently elucidated. We retrospectively analyzed 2194 recipients of HSCT who were CMV-seropositive (236 with letermovir prophylaxis and 1958 without prophylaxis against CMV). csCMVi was significantly less frequent in patients with letermovir prophylaxis than in those without (23.7% vs 58.7% at 100 days after HSCT, P < .001) and the same trend was seen when recipients of bone marrow (BM), peripheral blood stem cell (PBSC), or cord blood (CB) transplantation were separately analyzed. In recipients of BM, nonrelapse mortality (NRM) was significantly lower in the letermovir group at 6 months after HSCT (5.0% vs 14.9%, P = .018), and the same trend was observed in recipients of PBSCs (14.7% vs 24.8%, P = .062); however, there was no statistical significance at 1 year (BM, 21.1% vs 30.4%, P = .67; PBSCs, 21.2% vs 30.4%, P = .096). In contrast, NRM was comparable between recipients of CB with and without letermovir prophylaxis throughout the clinical course (6 months, 23.6% vs 24.3%, P =.92; 1 year, 29.3% vs 31.0%, P = .77), which was confirmed by multivariate analyses. In conclusion, the impact of letermovir prophylaxis on NRM and csCMVi should be separately considered according to graft sources.

Utility of allogeneic stem cell transplantation for adult Ph+ALL with complete molecular remission.

This study aimed to investigate the usefulness of allogeneic stem cell transplantation (allo-SCT) for Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) in the first complete remission (CR1) with complete molecular remission (CMR). We compared the outcomes between Ph+ALL patients who did or did not undergo allo-SCT in CR1. We included patients enrolled in the prospective clinical studies in the tyrosine kinase inhibitor era conducted by the Japan Adult Leukemia Study Group, who achieved CMR within 3 months. A total of 147 patients (allo-SCT: 101; non-SCT: 46) were eligible for this analysis. In the multivariate analyses, allo-SCT was significantly associated with both superior overall survival (OS) (adjusted hazard ratio (aHR): 0.54; 95% CI: 0.30-0.97; p = .04) and relapse-free survival (RFS) (aHR: 0.21; 95% CI: 0.12-0.38; p < .001). The 5-year adjusted OS and RFS were 73% and 70% in the allo-SCT cohort, whereas they were 50% and 20% in the non-SCT cohort. Despite the higher non-relapse mortality (aHR: 3.49; 95% CI: 1.17-10.4; p = .03), allo-SCT was significantly associated with a lower relapse rate (aHR: 0.10; 95% CI: 0.05-0.20; p < .001). In addition, allo-SCT was also associated with superior graft-versus-host disease-free, relapse-free survival (aHR: 0.43; 95% CI: 0.25-0.74; p = .002). Propensity score-matched analyses confirmed the results of the multivariate analyses. In patients who achieved CMR within 3 months, allo-SCT in CR1 had superior survival and lower relapse compared with the non-SCT cohort.

Comparison of Melphalan Dose in Patients with Myelodysplastic Syndrome Undergoing Allogeneic Transplantation with Reduced-Intensity Conditioning.

The present study compared lower-dose melphalan (80 mg/m2, FM80) and higher-dose melphalan (140 mg/m2, FM140) when administering reduced-intensity conditioning with fludarabine in adult patients with myelodysplastic syndrome (MDS) undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). We retrospectively analyzed nationwide registry data (2006 to 2019) and compared transplant outcomes between the 2 groups. Ninety-two patients (median age, 61 [interquartile range, 56 to 65] years) were assigned to the FM80 and FM140 groups by propensity score matching. The 3-year overall survival (OS) rate in the FM140 group (63.9%; 95% confidence interval [CI], 52.9% to 73.0%) was significantly higher than that in the FM80 group (54.2%; 95% CI, 37.1% to 52.1%) (P = .038). The FM140 group had a nonsignificantly (P = .095) lower 3-year cumulative incidence of relapse (15.5%; 95% CI, 8.9% to 23.8% versus 26.0%; 95% CI, 17.3% to 35.5%). The 3-year cumulative incidences of nonrelapse mortality were 22.3% (95% CI, 14.1% to 31.8%) and 23.7% (95% CI, 15.4% to 33.2%) in the FM80 and FM140 groups, respectively (P = .49). The beneficial effect of FM140 was more evident in patients with a poor cytogenetic risk. Our findings suggest the superiority of FM140 in patients with MDS undergoing allo-HSCT, especially in high-risk patients.

Comparison of standardized prophylactic high-dose and intrathecal methotrexate for DLBCL with a high risk of CNS relapse.

The efficacy of high-dose methotrexate (HD-MTX) for central nervous system (CNS) relapse prophylaxis in patients with high-risk diffuse large B-cell lymphoma (DLBCL) is controversial. We compared the prophylactic effects of HD-MTX and intrathecal methotrexate (IT-MTX) on CNS relapse in high-risk DLBCL, in a multicenter retrospective study. A total of 132 patients with DLBCL at high risk of CNS relapse who received frontline chemotherapy and IT-MTX from 2003 to 2013 (n = 34) or HD-MTX from 2014 to 2020 (n = 98) were included. After a median follow-up of 52 months (range: 9-174), 11 patients had isolated CNS relapse: six (6.1%) in the HD-MTX group and five (14.7%) in the IT-MTX group. The median time until CNS relapse was 38 months (range: 11-122), and the cumulative incidence of CNS relapse at 3 years was 3.9% in the HD-MTX group and 6.1% in the IT-MTX group (P = 0.93). Similar results were obtained after adjusting for background factors using propensity score-matched analysis (4.5% HD-MTX vs. 7.6% IT-MTX, P = 0.84). The CNS relapse rate in HD-MTX-treated patients was equivalent to that in IT-MTX patients, demonstrating that HD-MTX was not superior to IT-MTX in preventing CNS relapse.

Echocardiographic Findings of Malignant Lymphoma with Cardiac Involvement: A Single-center Retrospective Observational Study.

Objective Although malignant lymphoma (ML) can occur in every organ, diagnosing cardiac involvement without cardiac manifestations is difficult. We therefore investigated the incidence of cardiac involvement in ML in our hospital and clarified the transthoracic echocardiography (TTE) findings of cardiac involvement. Methods Patients with ML referred to our hospital between January 2013 and December 2019 were retrospectively reviewed. Patients During the study period, 453 patients were identified. The mean age was 64.9 years old, and 54% of the patients were men. Results Diffuse large B-cell lymphoma (DLBCL) was the most common lymphoma, followed by follicular lymphoma. Of the 453 patients, 394 (87.0%) underwent TTE at the initial diagnosis or during the clinical course. The performance rates of TTE in DLBCL, Hodgkin lymphoma, and mantle cell lymphoma were above 90%. Cardiac involvement was detected in 6 (five with DLBCL and one with B-cell lymphoma) (1.5%) of the 394 patients who underwent TTE. The involved lesions of the heart varied, and five patients had pericardial effusion. Five patients had a preserved left ventricular ejection fraction. All patients were treated with chemotherapy, and some were treated with radiation and surgery. Conclusion Cardiac involvement was observed in six (1.5%) of the patients with ML who underwent TTE. B-cell lymphoma, especially DLBCL, is a common ML with cardiac involvement. Although five patients had pericardial effusion, the involved lesions of the heart were not uniform. TTE is a useful imaging modality to noninvasively and repeatedly evaluate the tumor characteristics, response to ML treatment, and cardiac function.

Outcomes of transplant-eligible patients with myelodysplastic syndrome with excess blasts registered in an observational study: The JALSG-CS11-MDS-SCT.

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is the sole curative therapy for myelodysplastic syndrome (MDS). However, whether bridging therapy (BRT) including azacitidine (AZA) and combination chemotherapy (CCT) prior to allo-SCT should be performed is unclear. We analyzed BRT and the outcomes of patients with myelodysplastic syndrome with excess blasts (MDS-EB) who were ≤ 70 years old at the time of registration for a prospective observational study to clarify the optimal allo-SCT strategy for high-risk MDS. A total of 371 patients were included in this study. Among 188 patients (50.7%) who were considered for allo-SCT, 141 underwent allo-SCT. Among the patients who underwent allo-SCT, 64 received AZA, 29 received CCT, and 26 underwent allo-SCT without BRT as the initial treatment. Multivariate analysis identified BRT as an independent factor influencing overall survival (AZA vs. without BRT, hazard ratio [HR] 3.33, P = 0.005; CCT vs. without BRT, HR 3.82, P = 0.003). In multivariate analysis, BRT was independently associated with progression-free survival (AZA vs. without BRT: HR, 2.23; P = 0.041; CCT vs. without BRT: HR, 2.94; P = 0.010). Transplant-eligible patients with MDS-EB should undergo allo-SCT when clinically acceptable, and upfront allo-SCT without BRT may be superior to AZA or CCT.

Prognostic significance of the CFA ratio for newly diagnosed acute myeloid leukemia: A multicenter retrospective study.

The CFA ratio, calculated using pretreatment C-reactive protein (CRP), fibrinogen, and albumin levels (CRP × fibrinogen/albumin), was previously reported to be a significant prognostic factor for acute myeloid leukemia (AML). This multicenter retrospective study evaluated the prognostic value of the CFA ratio in 328 adult patients with newly diagnosed AML from April 2000 to March 2018. The median age was 49.5 years (range, 15-75 years), and 60.7% of the population were males. According to the European LeukemiaNet (ELN) risk classification, 67 patients (20.4%) were in the favorable-risk group, 197 patients (60.1%) in the intermediate-risk group, and 58 patients (17.7%) in the adverse-risk group. The median CFA ratio was 1.07 (0-67.69). Based on the calculated cutoff CFA ratio of 1.44, the cohort included 176 and 152 patients with low and high CFA ratios, respectively. At a median follow-up of 91.2 months, the 7-year overall survival (OS) and disease-free survival (DFS) rates were 51.2% and 48.6%, respectively, in the overall cohort. The 7-year OS rates were 61.7% and 39.0% in the low and high CFA ratio groups, respectively (p < 0.001). The 7-year DFS rates were 58.1% and 37.0% in the low and high CFA ratio groups, respectively (p = 0.004). In univariate analysis, age ≥50 years, male sex, ELN risk class, and comorbidities were associated with poor OS. Age, ELN risk class, comorbidities, and high CFA ratio were associated with poor OS in multivariate analysis. Subgroup analysis revealed that the CFA ratio was significant in the intermediate and adverse ELN risk classes. These findings indicate the prognostic significance of the CFA ratio in AML.

Clinical significance of total nucleated cell count in bone marrow of patients with acute lymphoblastic leukemia who underwent allogeneic hematopoietic stem cell transplantation.

The clinical implications of recipient bone marrow nucleated cell count (NCC) prior to allogeneic hematopoietic stem cell transplantation (allo-HSCT) remain unknown. We conducted a multicenter retrospective study to evaluate the clinical significance of bone marrow NCC prior to allo-HSCT in patients with acute lymphoblastic leukemia. Patients who were in remission and underwent the initial allo-HSCT were included and stratified into high- and low-NCC groups using an NCC of 10 × 104/µL as the cut-off. The 3-year overall survival (OS), non-relapse mortality (NRM), and relapse rates for the high- and low-NCC groups were 51.2 vs. 84.5% (p < 0.001), 27.5 vs. 6.5% (p < 0.001), and 31.1 vs. 24.4% (p = 0.322), respectively. The high-NCC group had significantly poorer OS and higher NRM when compared with the low-NCC group. In summary, high recipient bone marrow NCC is associated with higher NRM and lower OS following allo-HSCT.

[Primary mediastinal large B-cell lymphoma complicated with myotonic dystrophy].

A 39-year-old woman with myotonic dystrophy (DM) presented with syncope and was diagnosed with primary mediastinal large B-cell lymphoma, clinical stage IA. PET-CT revealed an upper mediastinal mass with high FDG uptake (SUVmax, 14.8). She had muscle weakness associated with DM, but her performance status was preserved. She was treated with 6 cycles of dose-adjusted EPOCH-R therapy and localized irradiation for the residual mass, without severe adverse events or recurrence of syncope. Patients with DM should be monitored for cardiac events and muscle weakness when undergoing lymphoma treatment.

Clinical significance of late CMV disease in adult patients who underwent allogeneic stem cell transplant.

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.

[Diffuse large B-cell lymphoma complicated with pancreatic fistula and peritonitis following initial chemotherapy].

A 59-year-old-woman complained of weight loss and abdominal pain. A CT scan revealed a 20 cm large retroperitoneal mass, and she was diagnosed with diffuse large B-cell lymphoma via biopsy of the mass. After 75% CHP therapy, she developed an acute abdomen and CT revealed generalized peritonitis. Amylase in the ascites fluid was elevated, and infiltration into the pancreas was suspected on CT before treatment, suggesting a pancreatic fistula caused by tumor shrinkage. Enterobacteria were found in ascites fluid culture, suggesting a gastrointestinal perforation complication. The patient was refractory to treatment, and death was confirmed due to progression of the primary disease. The pathological autopsy revealed diffuse pancreatic infiltration, suggesting that the pancreatic fistula was caused by pancreatic injury. Pancreatic fistula is a known complication of surgical procedures but is rarely caused by tumor shrinkage due to chemotherapy. Since there is no preventive method for pancreatic injury caused by tumor shrinkage, early diagnosis and early treatment of pancreatic fistula are critical, and ascites fluid analysis, including amylase, was thought to be useful for the diagnosis.

Bosutinib in Japanese patients with newly diagnosed chronic-phase chronic myeloid leukemia: final 3-year follow-up results of a phase 2 study.

Bosutinib has been evaluated for treatment of chronic-phase chronic myeloid leukemia (CP-CML) in several clinical studies, including in Japan. This open-label, single-arm, phase 2 study evaluated the efficacy and safety of bosutinib at a starting dose of 400 mg once daily in Japanese patients (n = 60) with newly diagnosed CP-CML. The minimum follow-up period was 3 years and median duration of treatment was 35.9 months. At study completion, 60% of patients were still on treatment. Cumulative rates of major molecular response (MMR), molecular response4 (MR4), and MR4.5 at any time were 70.0%, 53.3%, and 48.3%, respectively. No patient who achieved MMR or MR4 had a confirmed loss of response. No patient experienced on-treatment transformation to accelerated/blast phase or died within 28 days of the last bosutinib dose. Any-grade treatment-emergent adverse events (TEAEs) occurred in 100% (grade ≥ 3: 81.7%) of patients. The most common TEAEs were diarrhea (86.7%), increased alanine aminotransferase (55.0%), and increased aspartate aminotransferase (46.7%). No new safety signals emerged during the follow-up period. Bosutinib continues to demonstrate a favorable benefit/risk profile and is an important treatment option for Japanese patients with newly diagnosed CP-CML. Optimal management of TEAEs during initial treatment with bosutinib should be prioritized.Trial Registration: ClinicalTrials.gov ID: NCT03128411.

[Resolution of dasatinib-associated lymphadenopathy following discontinuation of dasatinib in patients with chronic myeloid leukemia].

This study reports two cases of dasatinib-associated lymphadenopathy (DAL). Case 1 involved a 58-year-old man diagnosed with chronic myelogenous leukemia (CML). After 13 months of starting on dasatinib treatment, a molecular response (MR) 4.5 was achieved. Due to the loss of MMR, dasatinib was discontinued at 39 months but restarted at 42 months. Right cervical lymphadenopathy appeared 51 months after starting the treatment. DAL was diagnosed based on the findings of a cervical lymph node biopsy. After dasatinib was switched to ponatinib, the lymphadenopathy disappeared without recurrence. In case 2, a 54-year-old man was diagnosed with CML. He was started on dasatinib and MR 4.5 was achieved after 6 months. Left cervical lymph node adenopathy appeared 21 months later, and a diagnosis of DAL was made based on the findings of a cervical lymph node biopsy. After discontinuation of dasatinib, cervical lymph node adenopathy disappeared without recurrence. The possibility of DAL should be considered if lymphadenopathy is observed during dasatinib treatment.

Clinical impact of cigarette smoking on the outcomes of allogeneic hematopoietic stem cell transplantation: a multicenter retrospective study.

Smoking is associated with a high risk for different diseases including respiratory tract infections in immunocompetent patients. However, data about the effects of cigarette smoking on the outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT) are limited. Therefore, we retrospectively investigated 608 patients aged ≥20 years with hematological disorders who received their first allo-HSCT at our group of hospitals between 2000 and 2015, and evaluated the impact of cigarette smoking before allo-HSCT on clinical outcomes by dividing patients into two groups according to the Brinkman index (BI) (nonsmokers or light smokers [BI: 0-500] and heavy smokers [BI: ≥ 500]). Multivariate analyses showed that heavy smoking was associated with a high 5-year cumulative incidence of chronic graft-versus-host disease (cGVHD) (hazard ratio [HR]: 1.73, 95% confidence interval [CI]: 1.15-2.61, p < 0.01). The 5-year overall survival (HR: 1.16, 95% CI: 0.86-1.58, p = 0.33) and disease-free survival (HR: 1.12, 95% CI: 0.83-1.52, p = 0.45) were similar between the two groups. Hence, cigarette smoking is correlated with cGVHD, although prospective studies must be conducted to further verify this result.

Clinical risk factors for patients with myelodysplastic syndromes undergoing allogeneic hematopoietic stem cell transplantation.

Objectives: Allogeneic hematopoietic stem cell transplantation (allo-HCT) is the only curative treatment for myelodysplastic syndromes (MDS), although predicting post-transplant outcomes remains inconclusive. This study evaluated patients who underwent allo-HCT for MDS to identify prognostic factors and develop a clinical risk model.Methods: We evaluated 55 patients between June 2000 and March 2015 to identify prognostic factors and develop a model for three-year overall survival (OS) and event-free survival (EFS). Cox regression analysis was performed on four factors: age ≥55 years; Hematopoietic Cell Transplant-Comorbidity Index >2; intermediate or worse cytogenetic status based on revised International Prognostic Scoring System; and unrelated donor status associated with poor OS in the univariate analysis. A clinical risk model was constructed using the sum of the regression coefficients and evaluated using receiver operating characteristic analysis and five-fold cross-validation.Results: Patient median age was 51 (range: 30-67) years. Median follow-up was 45.8 (range: 1.27-193) months; the three-year OS and EFS rates were 61.8% and 56.4%, respectively. The areas under the curves (AUCs) for OS and EFS were 0.738 and 0.778, respectively, and the average AUC for 50 times five-fold cross-validation were 0.711 and 0.723 for three-year OS and EFS, respectively.Conclusion: A four-clinical-risk-factor model that could effectively predict post-transplantation outcomes and help decision-making in MDS treatment was developed.

[Successful child delivery in treatment-free remission of chronic myeloid leukemia after discontinuation of dasatinib].

A 21-year-old woman was diagnosed with chronic myeloid leukemia in March 2014. The patient and her family did not wish to freeze eggs before dasatinib initiation. After 66 months of oral dasatinib administration and 40 months of MR4.5 maintenance, the patient requested to discontinue dasatinib due to a desire to conceive. MR4.5 maintenance was continued, and she achieved spontaneous pregnancy 6 months after dasatinib discontinuation. The patient gave birth to a normal baby 13 months later and was on MR4.5 maintenance 21 months after dasatinib discontinuation.

Dasatinib-based 2-step induction for adults with Philadelphia chromosome-positive acute lymphoblastic leukemia.

The standard treatment for adults with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) in Japan is imatinib-based chemotherapy followed by allogeneic hematopoietic stem cell transplantation (HSCT). However, ∼40% of patients cannot undergo HSCT in their first complete remission (CR1) because of chemotherapy-related toxicities or relapse before HSCT or older age. In this study, we evaluated dasatinib-based 2-step induction with the primary end point of 3-year event-free survival (EFS). The first induction (IND1) was dasatinib plus prednisolone to achieve CR, and IND2 was dasatinib plus intensive chemotherapy to achieve minimal residual disease (MRD) negativity. For patients who achieved CR and had an appropriate donor, HSCT during a consolidation phase later than the first consolidation, which included high-dose methotrexate, was recommended. Patients with pretransplantation MRD positivity were assigned to receive prophylactic dasatinib after HSCT. All 78 eligible patients achieved CR or incomplete CR after IND1, and 52.6% achieved MRD negativity after IND2. Nonrelapse mortality (NRM) was not reported. T315I mutation was detected in all 4 hematological relapses before HSCT. Fifty-eight patients (74.4%) underwent HSCT in CR1, and 44 (75.9%) had negative pretransplantation MRD. At a median follow-up of 4.0 years, 3-year EFS and overall survival were 66.2% (95% confidence interval [CI], 54.4-75.5) and 80.5% (95% CI, 69.7-87.7), respectively. The cumulative incidence of relapse and NRM at 3 years from enrollment were 26.1% and 7.8%, respectively. Dasatinib-based 2-step induction was demonstrated to improve 3-year EFS in Ph+ ALL. This study was registered in the UMIN Clinical Trial Registry as #UMIN000012173.