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Dive into the research topics where Kiyoshi Okazuka is active.

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Featured researches published by Kiyoshi Okazuka.


Leukemia & Lymphoma | 2017

Serum soluble interleukin-2 receptor level at diagnosis predicts transformation in patients with follicular lymphoma

Kento Umino; Shin-ichiro Fujiwara; Shoko Ito; Kiyomi Mashima; Daisuke Minakata; Hirofumi Nakano; Ryoko Yamasaki; Yasufumi Kawasaki; Miyuki Sugimoto; Masahiro Ashizawa; Kaoru Hatano; Kiyoshi Okazuka; Kazuya Sato; Iekuni Oh; Ken Ohmine; Takahiro Suzuki; Kazuo Muroi; Yoshinobu Kanda

Abstract We evaluated 121 patients with follicular lymphoma (FL) and analyzed the association between the soluble interleukin-2 receptor (sIL-2R) level at diagnosis and the cumulative incidence of transformation. By a receiver-operating characteristic analysis, we determined a cutoff value of sIL-2R for transformation at 4360 U/mL to classify patients into two groups. Patients in the high sIL-2R group showed a shorter progression-free survival (PFS) and shorter disease-specific survival (DSS) (p < 0.001 and p = 0.018). Furthermore, the cumulative incidence of transformation in the high sIL-2R group was higher than that in the low sIL-2R group (40.9% vs. 7.3% at 5 years, p < 0.001). In a multivariate analysis, high sIL-2R was an independent predictive risk factor for transformation (HR 7.42, 95% CI: 2.75–20.0, p < 0.001). This study showed that the sIL-2R level at diagnosis may be a prognostic factor for transformation, PFS, and DSS in patients with FL.


Hematology | 2017

CD25 as an adverse prognostic factor in elderly patients with acute myeloid leukemia.

Shin-ichiro Fujiwara; Kazuo Muroi; Chihiro Yamamoto; Kaoru Hatano; Kiyoshi Okazuka; Kazuya Sato; Iekuni Oh; Ken Ohmine; Takahiro Suzuki; Keiya Ozawa

ABSTRACT Objectives: CD25 has been reported to be highly expressed in leukemia stem cells and correlated with adverse outcomes in young patients with acute myeloid leukemia (AML). However, the significance of CD25 expression in elderly patients with AML has not yet been investigated. Methods: We retrospectively analyzed 154 newly diagnosed AML patients aged 60 years or over by flow cytometry. Results: CD25-positive AML was characterized by high white blood cell counts, secondary AML, rare favorable karyotypes, and positivity for CD34 and CD7 antigens, compared with CD25-negative AML. CD25 positivity was significantly correlated with an inferior complete remission (CR), event-free survival (EFS), and overall survival. Multivariate analysis showed CD25 positivity to be a significant prognostic predictor of CR and EFS. A regimen of low-dose cytarabine and aclarubicin combined with granulocyte-colony-stimulating factor (CAG) led to higher CR rates in the CD25-positive AML patients than intensive chemotherapies. CD25 expression was increased at relapse and in the development of leukemic status from myelodysplastic syndrome or myeloproliferative neoplasm. Discussion: An effective treatment strategy for elderly patients with CD25-positive AML has not been established. Further studies are needed to evaluate the effect of a CAG regimen and allogenic stem cell transplantation in patients. Conclusion: CD25 is an independent prognostic factor in elderly AML patients. Alternative therapies for CD25-positive elderly AML patients are needed.


Leukemia Research | 2016

A low-dose cytarabine, aclarubicin and granulocyte colony-stimulating factor priming regimen versus a daunorubicin plus cytarabine regimen as induction therapy for older patients with acute myeloid leukemia: A propensity score analysis

Daisuke Minakata; Shin-ichiro Fujiwara; Shoko Ito; Kiyomi Mashima; Kento Umino; Hirofumi Nakano; Yasufumi Kawasaki; Miyuki Sugimoto; Ryoko Yamasaki; Chihiro Yamamoto; Masahiro Ashizawa; Kaoru Hatano; Kiyoshi Okazuka; Kazuya Sato; Iekuni Oh; Ken Ohmine; Takahiro Suzuki; Kazuo Muroi; Yoshinobu Kanda

This retrospective analysis compared the efficacy of intensive induction therapy consisting of daunorubicin and cytarabine (DNR-AraC) to that of less-intensive therapy including low-dose cytarabine, aclarubicin and granulocyte colony-stimulating factor priming (CAG). Patients aged 60 years or older who were newly diagnosed as acute myeloid leukemia (AML) were analyzed. Sixty-four and 48 patients were treated with DNR-AraC and CAG, respectively. The complete remission rates, 3-year overall survival and event-free survival in the DNR-AraC group were significantly superior to those in the CAG group (65.6% vs. 29.2%, p<0.001, 38.4% vs. 12.3%, p=0.0033, and 20.3% vs. 7.8%, p=0.0030, respectively), although these differences were not statistically significant in multivariate analyses. Next, we calculated a propensity score for selecting the CAG regimen from six factors. The DNR-AraC regimen was associated with better survival than the CAG regimen in a low propensity score group, but there was no difference in survival between regimens in a high propensity score group. Intensive therapy should be performed for patients with sufficient general and comorbid conditions, but less-intensive therapy may be sufficient for patients with higher age, myelodysplasia-related changes, and lower white blood cell counts, which were relevant factors in the propensity score calculation.


Acta Haematologica | 2017

High-Dose Methotrexate and Cytarabine-Based Multi-Agent Chemotherapy (Modified Bonn Protocol) for Systemic Lymphoma with CNS Involvement

Kento Umino; Shin-ichiro Fujiwara; Kazuya Sato; Daisuke Minakata; Hirofumi Nakano; Ryoko Yamasaki; Yasufumi Kawasaki; Miyuki Sugimoto; Chihiro Yamamoto; Kaoru Hatano; Kiyoshi Okazuka; Iekuni Oh; Ken Ohmine; Takahiro Suzuki; Kazuo Muroi; Yoshinobu Kanda

The prognosis of patients with systemic lymphoma with central nervous system (CNS) involvement is very poor and there is no established standard therapy. We retrospectively analyzed 18 patients (4 untreated and 14 relapsed) with systemic lymphoma with CNS involvement who received methotrexate and cytarabine-based multiagent chemotherapy (modified Bonn protocol). Complete and partial responses were achieved in 56 and 22% of the patients, respectively. The 1-year overall survival (OS) and progression-free survival (PFS) was 81.0 and 39.2%, respectively. Patients with parenchymal involvement showed a better 1-year PFS than those with either leptomeningeal involvement or both. In a multivariate analysis, poor performance status (PS) was the only independent prognostic factor for the 1-year OS and PFS (HR 10.8, 95% CI 1.09-108, p = 0.042; HR 20.8, 95% CI 2.39-181, p = 0.006, respectively). Grade 4 neutropenia and thrombocytopenia occurred in 17 patients each (94%), but there were no grade 4 nonhematopoietic adverse events. The modified Bonn protocol resulted in relatively favorable response and survival, and provided clinical benefits to patients with good PS, in particular. This study demonstrated that the modified Bonn protocol could be a feasible and encouraging treatment approach for lymphoma with CNS and systemic involvement.


Hematological Oncology | 2017

The prognostic significance of rapid peripheral blood blast clearance during the initial course of induction chemotherapy in young patients with de novo acute myeloid leukemia

Hirofumi Nakano; Shin-ichiro Fujiwara; Shoko Ito; Kiyomi Mashima; Kento Umino; Daisuke Minakata; Ryoko Yamasaki; Yasufumi Kawasaki; Miyuki Sugimoto; Masahiro Ashizawa; Chihiro Yamamoto; Kaoru Hatano; Kiyoshi Okazuka; Kazuya Sato; Iekuni Oh; Ken Ohmine; Takahiro Suzuki; Kazuo Muroi; Yoshinobu Kanda

The early clearance of blast cells in peripheral blood (PB) during induction chemotherapy can predict the clinical outcome in acute leukemia. We retrospectively analyzed the kinetics of white blood cell (WBC) count, blast cell percentage (BCP), and blast cell count (BCC) in PB in 78 patients with de novo acute myeloid leukemia who underwent a uniform induction chemotherapy between December 2001 and December 2015 at Jichi Medical University. By a repeated‐measures analysis of variance, the interaction of the decline in BCP with the achievement of complete remission (CR) was stronger than those of the decline in WBC or BCC. A receiver operating characteristic curve analysis for the achievement of CR showed that the areas under the curve for the decline in WBC, BCP, and BCC were 0.592, 0.703, and 0.634, respectively, and a decline in BCP of 9.25%/day within 4 or 5 days from induction chemotherapy was the optimal cutoff value. A multivariate analysis showed that a rapid decline in BCP (≥9.25%/day) was a significant predictive factor for CR, independent of the cytogenetic risk (p = 0.0096). A rapid decline in BCP during the first 5 days of induction chemotherapy may be a good predictor of CR. Copyright


Leukemia & Lymphoma | 2016

Dose-reduced combination of mitoxantrone, etoposide, and cytarabine (miniMEC) for relapsed and refractory acute leukemia.

Chihiro Yamamoto; Shoko Ito; Kiyomi Mashima; Kento Umino; Daisuke Minakata; Ryoko Yamasaki; Yasufumi Kawasaki; Miyuki Sugimoto; Hirofumi Nakano; Masahiro Ashizawa; Kiyoshi Okazuka; Kaoru Hatano; Kazuya Sato; Iekuni Oh; Shin-ichiro Fujiwara; Ken Ohmine; Takahiro Suzuki; Kazuo Muroi; Yoshinobu Kanda

Abstract The combination of mitoxantrone (MIT), etoposide (ETP), and cytarabine (Ara-C) (MEC) is a frequently used salvage therapy for acute leukemia, but has been associated with severe myelosuppression. Therefore, we investigated the miniMEC regimen with reduced doses of AraC and MIT. Thirteen ALL and 44 AML patients, all relapsed or refractory, received miniMEC, which consisted of MIT at 8 mg/m2 for 3 d, ETP at 100 mg/m2 for 5 d, and Ara-C at 100 mg/m2 infused over 24 h for 7 d. CR + CRi was achieved in eight ALL patients (61.5%) and 16 AML patients (36.4%). Median duration of neutropenia was 30 d (range, 1–50). Thirty-one patients (54.4%) subsequently received allogeneic stem cell transplantation (SCT), and overall survival was significantly improved in this group (median OS 161 versus 481 d, p = 0.006). We concluded that miniMEC is a safe and effective bridging therapy to SCT.


International Journal of Hematology | 2016

Efficacy of combination therapy with anti-thymocyte globulin and cyclosporine A as a first-line treatment in adult patients with aplastic anemia: a comparison of rabbit and horse formulations

Takahiro Suzuki; Hiroyuki Kobayashi; Yasufumi Kawasaki; Kiyoshi Okazuka; Kaoru Hatano; Shin-ichiro Fujiwara; Iekuni Oh; Ken Ohmine; Yoshinobu Kanda


Annals of Hematology | 2016

Retrospective evaluation of the MEAM regimen as a conditioning regimen before autologous peripheral blood stem cell transplantation for lymphoma in two centers with different dosing schedules of melphalan

Miyuki Sugimoto; Shoko Ito; Kiyomi Mashima; Kento Umino; Daisuke Minakata; Hirofumi Nakano; Ryoko Yamasaki; Yasufumi Kawasaki; Masahiro Ashizawa; Chihiro Yamamoto; Shin-ichiro Fujiwara; Kiyoshi Okazuka; Kaoru Hatano; Kazuya Sato; Iekuni Oh; Ken Ohmine; Takahiro Suzuki; Kazuo Muroi; Shinichi Kako; Yoshinobu Kanda


Journal of Clinical and Experimental Hematopathology | 2013

CD56 Expression in Normal Immature Granulocytes after Allogeneic Hematopoietic Stem Cell Transplantation

Kazuo Muroi; Shin-ichiro Fujiwara; Raine Tatara; Miyuki Sugimoto; Chihiro Yamamoto; Eisuke Uehara; Akiko Meguro; Kaoru Hatano; Kiyoshi Okazuka; Iekuni Oh; Ken Ohmine; Takahiro Suzuki; Masaki Mori; Tadashi Nagai; Keiya Ozawa


Blood | 2014

CD25 Expression Is Associated with Inferior Clinical Outcomes in Elderly Patients with Acute Myeloid Leukemia

Shin-ichiro Fujiwara; Kazuo Muroi; Raine Tatara; Kiyoshi Okazuka; Sato Kazuya; Iekuni Oh; Ken Ohmine; Takahiro Suzuki; Tadashi Nagai

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Iekuni Oh

Jichi Medical University

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Ken Ohmine

Jichi Medical University

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Kazuo Muroi

Jichi Medical University

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Kaoru Hatano

Jichi Medical University

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Kazuya Sato

Jichi Medical University

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