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Dive into the research topics where Toru Masaoka is active.

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Featured researches published by Toru Masaoka.


Scandinavian Journal of Infectious Diseases | 2004

A Multicenter, Open-Label Clinical Study of Micafungin (FK463) in the Treatment of Deep-seated Mycosis in Japan

Shigeru Kohno; Toru Masaoka; Hideyo Yamaguchi; Takeshi Mori; Akio Urabe; Akira Ito; Yoshihito Niki; Hideo Ikemoto

The efficacy and safety of micafungin (FK463), which is a new lipopeptide antifungal agent of the echinocandin class and is active against both Aspergillus and Candida species, were investigated in patients with deep-seated mycosis in this study. 70 patients were treated with micafungin 12.5–150 mg/d intravenously for up to 56 d. The overall clinical response rates were 60% (6/10) in invasive pulmonary aspergillosis, 67% (6/9) in chronic necrotizing pulmonary aspergillosis, 55% (12/22) in pulmonary aspergilloma, 100% (6/6) in candidemia, and 71% (5/7) in esophageal candidiasis. The response rates for patients with prior antifungal treatment which was considered ineffective or toxic, were similar to rates for patients without prior treatment. Mycological eradication was observed in patients infected with Aspergillus fumigatus, Aspergillus flavus, Aspergillus terreus, Aspergillus niger, Candida albicans, Candida glabrata, or Candida krusei. Adverse events related to micafungin were reported in 21 patients (30%), and there was no dose-related occurrence of any adverse event. It is concluded that treatment with micafungin as monotherapy seems to be effective and safe in patients with deep-seated mycosis.


Bone Marrow Transplantation | 2001

Phase III study comparing tacrolimus (FK506) with cyclosporine for graft-versus-host disease prophylaxis after allogeneic bone marrow transplantation.

Akira Hiraoka; Y. Ohashi; Shinichiro Okamoto; Y. Moriyama; T. Nagao; Yasuhiro Kodera; Akihisa Kanamaru; Hiroo Dohy; Toru Masaoka

We report the results of a phase III trial comparing tacrolimus (FK506) with cyclosporine for GVHD prophylaxis after allogeneic BMT. From February 1995 to July 1996, 136 patients were enrolled and followed up to September 1997. During the first 100 days post-transplant the incidence of grade II–IV acute GVHD (the primary end-point) was lower in the tacrolimus group (17.5%) compared with the cyclosporine group (48.0%, P < 0.0001). A significant difference was observed between the tacrolimus and cyclosporine groups when subset analyses were performed based on recipients from HLA-matched siblings (13.3% vs 41.3%, P = 0.015) or donors other than HLA-matched siblings (21.4% vs 53.8%, P = 0.0029). The incidence of chronic GVHD (47.3% and 47.8%) and Kaplan–Meier estimate of overall survival (62.9% and 65.2%) were similar between the tacrolimus and cyclosporine groups, respectively. The overall leukemia relapse rate was not significantly different between the tacrolimus and cyclosporine groups (19.6% and 11.4%, respectively). However, the relapse rate among recipients from HLA-matched siblings was significantly higher in the tacrolimus group (30.9%) compared with the cyclosporine group (3.6%, P = 0.013). These results suggest the merit of tacrolimus for the prophylaxis of acute GVHD, but a lack of merit for a graft-versus-leukemia effect among recipients from HLA-matched sibling donors. Bone Marrow Transplantation (2001) 28, 181–185.


British Journal of Haematology | 1992

Levels of complement regulatory proteins, CD35 (CR1), CD46 (MCP) and CD55 (DAF) in human haematological malignancies

Tomoko Hara; Ayako Kojima; Hiroko Fukuda; Toru Masaoka; Yasuo Fukumori; Misako Matsumoto; Tsukasa Seya

Summary. Levels of the membrane complement regulatory proteins. C3b/C4b receptor (CR1, CD35), membrane cofactor protein (MCP, CD46), and decay‐accelerating factor (DAF, CD55), expressed on cells from patients with haematological malignancies and normal subjects were assessed by flowcytometry using the respective monoclonal antibodies (mAbs). All myeloid and most lymphoid leukaemia samples tested were CR1‐negative: two of the 42 leukaemia samples expressed minute amounts of CR1. Lack of CR1 in leukaemia cells was confirmed with two mAbs raised against CR1, 31R, and 243R, which recognized different epitopes and induced different degrees of CR1‐mediated fluorescent shift on flow‐cytometry in granulocytes and erythrocytes. MCP was increased in most chronic myelogenous leukaemia (CML) and chronic lymphocytic leukaemia (CLL), and was also increased in majority of acute nonlymphocytic leukaemia (ANLL), acute lymphocytic leukaemia (ALL) and non‐Hodgkins lymphoma (NHL). Levels of DAF were also high in CML and CLL, and were variable in other types of leukaemia: some were DAF‐negative while others expressed extremely high levels of DAF. In CML patients, the high level of MCP and the lack of CR1 were normalized after medical treatment. These results are in agreement with the data obtained with human leukaemia cell lines, and support the hypothesis that CR1 is essentially a differentiated cell antigen and that a high level of MCP reflects some malignant transformation or an immature stage in blood cells.


British Journal of Haematology | 2002

Efficacy of granulocyte colony‐stimulating factor in the treatment of acute myelogenous leukaemia: a multicentre randomized study

Kensuke Usuki; Akio Urabe; Toru Masaoka; Ryuzo Ohno; Hideaki Mizoguchi; Nobuyuki Hamajima; Tamotsu Miyazaki; Yousirou Niitsu; Yutaka Yoshida; Akira B. Miura; Akira Shibata; Tsukasa Abe; Yasusada Miura; Yasuo Ikeda; Takeo Nomura; Tadami Nagao; Hidehiko Saitou; Shigeru Shirakawa; Minoru Ohkuma; Tamotsu Matsuda; Toru Nakamura; Atsushi Horiuchi; Atsushi Kuramoto; Ikurou Kimura; Syozo Irino; Yoshiyuki Niho; Kiyoshi Takatsuki; Masao Tomonaga; Haruto Uchino; Fumimaro Takaku

Summary. To investigate the efficacy and safety of granulocyte colony‐stimulating factor (G‐CSF) in patients with acute myelogenous leukaemia, a multicentre randomized study was performed. From October 1993 to September 1996, 270 patients with newly diagnosed acute myelogenous leukaemia were randomized to G‐CSF or control groups after remission induction therapy. The G‐CSF group received G‐CSF (Filgrastim) from 48u2003h after the completing chemotherapy until the absolute neutrophil count exceeded 1·5u2003×u2003109/l. The control group did not receive G‐CSF unless severe infection occurred. There were 245 evaluable patients (120 and 125 in the G‐CSF and control groups respectively). The complete remission rate was similar in the G‐CSF and control groups (80·8% versus 76·8%), as was the 5‐year probability of disease‐free survival (34·5% versus 33·6%) and overall survival (42·7% versus 35·6%). Neutrophil recovery was significantly faster in the G‐CSF group than in the control group (12u2003d versus 18u2003d, Pu2003=u20030·0001). The median duration of febrile neutropenia was significantly shorter in the G‐CSF group than in the control group (3u2003d versus 4u2003d, Pu2003=u20030·0001). In conclusion, prophylactic administration of G‐CSF after remission induction therapy for acute myelogenous leukaemia is safe and useful even in patients without infection on completing chemotherapy.


International Journal of Hematology | 2005

Long-term Results of a Multicenter Randomized, Comparative Trial of Modified CHOP versus THP-COP versus THP-COPE Regimens in Elderly Patients with Non-Hodgkin's Lymphoma

Mayumi Mori; Kiyoshi Kitamura; Michihiko Masuda; Tomomitsu Hotta; Tamotsu Miyazaki; Akira B. Miura; Hideaki Mizoguchi; Akira Shibata; Hidehiko Saito; Tamotsu Matsuda; Toru Masaoka; Mine Harada; Yoshiyuki Niho; Fumimaro Takaku

In treating elderly non-Hodgkin’s lymphoma (NHL) patients, it is particularly important to use drugs that have a low incidence of adverse events and high efficacy. In this multicenter study, THP (pirarubicin)-COP (cyclophosphamide, vincristine, and prednisolone) was compared to two thirds dosage of full CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone) regimen with regard to both adverse events and efficacy. For a third group, etoposide (E) was added to the THP-COP regimen (THP-COPE) in order to achieve high dose-intensity. Subjects were 486 previously untreated patients, aged 65 or older (range, 65–92 years; median, 74 years), with NHL. Subjects were randomly assigned to receive THP-COP, two thirds CHOP, or THP-COPE. Four hundred and forty-three patients were assessed for response and followed for 8 years after the last subject registered. The complete remission rates for the THP-COP, CHOP, and THP-COPE groups were 42.5%, 41.4%, and 48.0%, respectively. There was no difference in overall survival or progression-free survival among these 3 groups. In aggressive lymphoma, there was also no difference in complete response (CR) rate (45.3% in THP-COP, 44.9% in CHOP, 48.0% in THP-COPE), overall survival, and progression-free survival among these groups. The 5- and 8-year survival rates for all patients were 29.4% and 18.7%, respectively. The 5- and 8-year survival rates for patients with aggressive lymphoma were 27.4% and 17.4%, respectively. Although long-term survival for patients with aggressive lymphoma on our regimens was not worse compared to previous reports, the CR rate was lower. Because severe adverse events were not observed, higher dose chemotherapy may be directed to achieve better CR rates. In patients with T-cell-type lymphoma, the CR rate was greater after treatment with THP-COP (51.4%) or THP-COPE (57.7%) compared to treatment with CHOP (19.4%). Pirarubicin may be more useful for T-cell lymphoma than doxorubicin. Because adverse cardiac events were reported only in CHOP, adverse cardiac events might be low in the THP group.


Cancer Chemotherapy and Pharmacology | 1994

Nation-wide randomized comparative study of doxorubicin, vincristine and prednisolone combination therapy with and without L-asparaginase for adult acute lymphoblastic leukemia

Eiichi Nagura; Kiyoji Kimura; Kazumasa Yamada; Kazuo Ota; Tadashi Maekawa; Fumimaro Takaku; Haruto Uchino; Toru Masaoka; Ichita Amaki; Kohei Kawashima; Ryuzo Ohno; Takeo Nomura; Jun-ichi Hattori; Setsuko Kawamura; Akira Shibata; Shigeru Shirakawa; Nobuyuki Hamajima

A randomized clinical trial of combination chemotherapy for adult acute lymphoblastic leukemia (ALL) with doxorubicin, vincristine and prednisolone with and withoutL-asparaginase (AdVP vs L-AdVP) was conducted, involving 58 institutions throughout Japan. After reaching complete remission (CR), patients were treated with the same regimen for more than 2 years. Among 166 evaluable cases of the 198 cases enrolled, CR rates were 63.1% (53/84) with AdVP and 64.6% (53/82) with L-AdVP (P=0.837). Median survival times and 7-year survival rates were 12.7 months and 21.2% with AdVP, and 16.0 months and 22.3% with L-AdVP (P=0.955 by generalized Wilcoxon test [GW],P=0.952 by log-rank test [LR]). Median diseasefree survival times and 7-year survival rates were 13.5 months and 23.8% with AdVP and 17.0 months and 30.6% with L-AdVP, showing some increments for L-AdVP but no statistical significance (P=0.141 by GW,P=0.300 by LR). Among the cases of extramurally confirmed FAB subtypes, CR rates were 75.9% (63/83) for the L1 subtype and 51.3% (39/76) for the L2 subtype (P=0.001). As to adverse effects, pancreatitis was complicated more frequently in L-AdVP than in AdVP (P=0.039). Other side effects such as hyperbilirubinemia, diabetes mellitus, diarrhea and hypofibrinogenemia were observed more frequently with L-AdVP, but with no statistical significance. Thus, addition of a single course of L-asparaginase in the induction phase of combination chemotherapy with doxorubicin, vincristine and prednisolone did not significantly enhance the effect of antileukemic treatment of adult ALL.


Cancer Immunology, Immunotherapy | 1984

A randomized trial of chemoimmunotherapy of acute nonlymphocytic leukemia in adults using a protein-bound polysaccharide preparation

Ryozo Ohno; Kazumasa Yamada; Toru Masaoka; Toshiteru Ohshima; Ichita Amaki; Yutaka Hirota; Noboru Horikoshi; Atsushi Horiuchi; Kuniyuki Imai; Ikuro Kimura; Koichi Kitajima; Hiroyuki Nakamura; Toru Nakamura; Yoshiro Ohta; Yasunobu Sakai; Mineya Tanaka; Kazuo Tsubaki; Haruto Uchino; Nobuya Ogawa; Kiyoji Kimura

SummaryThe effect of immunotherapy with a protein-bound polysaccharide preparation termed PSK on remission duration and survival of adults with acute nonlymphocytic leukemia (ANLL) was studied in a prospective randomized cooperative trial. After having achieved complete remission and receiving a consolidation therapy, 73 patients were randomized either to maintenance chemotherapy or to maintenance chemotherapy plus immunotherapy with PSK. Ultimately 36 patients in the chemotherapy group and 31 in the chemoimmunotherapy group were evaluable. Six months after the last entry, immunotherapy with PSK showed a borderline beneficial effect on remission duration (P=0.089) and on duration of survival (P=0.062). When the data were analyzed 12, 18, and 24 months after the last entry there were no significant differences in duration of remission and survival between the two groups. However, analysis of the data of patients who had maintained complete remission for more than 270 days revealed that immunotherapy had a suggestive beneficial effect (P=0.105), prolonging the 50% remission period by 418 days (885 vs 467 days). Thus, immunotherapy with PSK seems to be active in the treatment of adult ANLL when used for maintenance therapy in combination with chemotherapy, especially in patients with a good prognosis.


Cancer | 1985

Treatment of acute myelogenous leukemia in adults with N4-behenoyl-1-β-D-arabinofuranosylcytosine

Kiyoji Kimura; Ryuzo Ohno; Ichita Amaki; Kenichi Hattori; Yutaka Hirota; Akira Hoshino; Michito Ichimaru; Munemoto Ito; Ikuo Kimura; Tadashi Maekawa; Toru Masaoka; Toru Nakamura; Makoto Ogawa; Masao Oguro; Kazuo Ohta; Shigeyuki Osamura; Masanori Shimoyama; Fumimaro Takaku; Yoshiro Uzuka; Kazumasa Yamada

Forty‐five previously‐untreated adult patients with acute myelogenous leukemia (AML) were treated with N4‐behenoyl‐1‐β‐D‐arabinofuranosyl‐cytosine (BHAC) in a multi‐institutional cooperative study. Among 41 evaluable patients, 15 (36.6%) achieved complete remission (CR) and 10 (24.4%) achieved partial remission by daily administration of 3 to 8 mg/kg of BHAC. Higher daily doses (5 mg/kg or more) produced higher CR rates, and all of the CR were observed among the patients receiving a total BHAC dosage of 50 mg/kg or more in a period of 10 days or more. The side effects were mild and acceptable: nausea–anorexia was observed in 27% of the patients and vomiting in 17%. The results of this study thus indicate BHAC to be effective for remission induction of AML, and to deserve further clinical trials in combination with other anti‐leukemic drugs. Cancer 56: 1913‐1917, 1985.


Leukemia & Lymphoma | 1994

Distribution of C3-Step Regulatory Proteins of the Complement System, CD35 (CRl), CD46 (MCP), and CD55 (DAF), in Hematological Malignancies

Tsukasa Seya; Misako Matsumoto; Tomoko Hara; Michiyo Hatanaka; Toru Masaoka; Hitoshi Akedo

The distribution and levels of three membrane proteins, CD35, CD46, and CD55, which serve as complement regulators, were examined in normal peripheral blood and hematologically malignant cells. CD35 was negative in most leukemia cells regardless of the type of leukemia, although granulocytes, monocytes, and some populations of lymphocytes were CD35+. CD46 was present in all blood cells except erythrocytes, and levels were 2-8 times higher in most leukemia cells than in their mature counterparts, particularly in CML and CLL cells, except for those of B cell lineage. CD55, a widely-distributed phosphatidyl inositol-anchored protein, was more frequently lost in NHL cells than in other types of hematological malignancies. In this review, we discuss the roles, mechanisms, and clinical applications of cell-associated complement regulatory proteins in hematological malignancies.


Cancer | 1986

Fibrinolysis in patients with acute promyelocytic leukemia and disseminated intravascular coagulation during heparin therapy

Shingi Imaoka; Takaaki Ueda; Hirotoshi Shibata; Toru Masaoka; Mutsuko Ogawa; Yo Sasaki; Takeshi Iwanaga; Toshio Terasawa

Two patients diagnosed as having acute promyelocytic leukemia (APL) and disseminated intravascular coagulation (DIG) were closely followed by serial fibrinolysis and coagulation studies from the day of admission until completion of the first course of chemotherapy. One patient was treated with intravenous heparin and Trasylol (Bayer AG, West Germany) and the other received heparin therapy without Trasylol. In Patient 1, hyperfibrinolytic activity, not observed during the administration of Trasylol, developed with its discontinuance. In Patient 2, hyperfibrinolysis was observed coincidentally with a decrease in APL cells due to chemotherapy. These results indicate that hyperfibrinolysis in APL is not associated with DIC.

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Hirotoshi Shibata

Gulf Coast Regional Blood Center

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Kiyoji Kimura

Memorial Hospital of South Bend

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