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Dive into the research topics where Kazutaka Sunami is active.

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Featured researches published by Kazutaka Sunami.


Blood | 2010

Hepatic toxicity and prognosis in hepatitis C virus–infected patients with diffuse large B-cell lymphoma treated with rituximab-containing chemotherapy regimens: a Japanese multicenter analysis

Daisuke Ennishi; Yoshinobu Maeda; Nozomi Niitsu; Minoru Kojima; Koji Izutsu; Jun Takizawa; Shigeru Kusumoto; Masataka Okamoto; Masahiro Yokoyama; Yasushi Takamatsu; Kazutaka Sunami; Akira Miyata; Kayoko Murayama; Akira Sakai; Morio Matsumoto; Katsuji Shinagawa; Akinobu Takaki; Keitaro Matsuo; Tomohiro Kinoshita; Mitsune Tanimoto

The influence of hepatitis C virus (HCV) infection on prognosis and hepatic toxicity in patients with diffuse large B-cell lymphoma in the rituximab era is unclear. Thus, we analyzed 553 patients, 131 of whom were HCV-positive and 422 of whom were HCV-negative, with DLBCL treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (RCHOP)-like chemotherapy. Survival outcomes and hepatic toxicity were compared according to HCV infection. The median follow-up was 31 and 32 months for patients who were HCV-positive and HCV-negative, respectively. HCV infection was not a significant risk factor for prognosis (3-year progression-free survival, 69% vs 77%, P = .22; overall survival, 75% vs 84%, P = .07). Of 131 patients who were HCV-positive, 36 (27%) had severe hepatic toxicity (grade 3-4), compared with 13 of 422 (3%) patients who were HCV-negative. Multivariate analysis revealed that HCV infection was a significant risk factor for severe hepatic toxicity (hazard ratio: 14.72; 95% confidence interval, 6.37-34.03; P < .001). An exploratory analysis revealed that pretreatment transaminase was predictive of severe hepatic toxicity. HCV-RNA levels significantly increased during immunochemotherapy (P = .006). These results suggest that careful monitoring of hepatic function and viral load is indicated during immunochemotherapy for HCV-positive patients.


Bone Marrow Transplantation | 1997

The effects of a simplified method for cryopreservation and thawing procedures on peripheral blood stem cells

Y Katayama; T Yano; Akihiro Bessho; S Deguchi; Kazutaka Sunami; Naira Mahmut; Katsuji Shinagawa; Eijiro Omoto; Shigeyoshi Makino; Toshihiro Miyamoto; Shin-ichi Mizuno; T Fukuda; Tetsuya Eto; Tomoaki Fujisaki; Yuju Ohno; S Inaba; Yoshiyuki Niho; Mine Harada

A simplified method for cryopreservation at −80°C of peripheral blood stem cells (PBSC) has been increasingly used for autologous PBSC transplantation in Japan. Although this method, using 6% hydroxyethyl starch (HES) and 5% dimethyl sulfoxide (DMSO) as a cryoprotectant without rate-controlled freezing, has several advantages over the conventional method using 10% DMSO with rate-controlled freezing, little is known about effects of long-term cryopreservation for years and thawing process on hematopoietic progenitors. We examined the recovery rates of BFU-E and CFU-GM in sample tubes cryopreserved by the simplified method under various conditions as follows: (1) long-term storage for 1–5 years; (2) DMSO exposure for 1 h after rapid thawing; and (3) thawing at a lower temperature other than 37°C. In our study, we found that the recovery rates of BFU-E and CFU-GM were not affected by the length of cryopreservation period; they remained at more than 70% on average for 16–61 months. In our hands, a 1-h exposure to DMSO after rapid thawing was not toxic for hematopoietic progenitors. Furthermore, there was no significant difference in the recovery rates of BFU-E and CFU-GM between thawing at 37°C and 20°C. These observations indicate that PBSC cryopreserved for at least 5 years by the simplified method can be used clinically without losing hematopoietic activity, and suggest that hematopoietic activity of the thawed PBSC may be unaffected when PBSC are infused slowly within 60 min or even when PBSC are thawed gradually at room temperature.


Haematologica | 2010

Prognostic factors and outcomes of adult patients with acute myeloid leukemia after first relapse

Saiko Kurosawa; Takuhiro Yamaguchi; Shuichi Miyawaki; Naoyuki Uchida; Toru Sakura; Heiwa Kanamori; Kensuke Usuki; Takuya Yamashita; Yasushi Okoshi; Hirohiko Shibayama; Hirohisa Nakamae; Momoko Mawatari; Kazuo Hatanaka; Kazutaka Sunami; Manabu Shimoyama; Naohito Fujishima; Yoshinobu Maeda; Ikuo Miura; Yoichi Takaue

Background Patients with acute myeloid leukemia who are treated with conventional chemotherapy still have a substantial risk of relapse; the prognostic factors and optimal treatments after relapse have not been fully established. We, therefore, retrospectively analyzed data from patients with acute myeloid leukemia who had achieved first complete remission to assess their prognosis after first relapse. Design and Methods Clinical data were collected from 70 institutions across the country on adult patients who were diagnosed with acute myeloid leukemia and who had achieved a first complete remission after one or two courses of induction chemotherapy. Results Among the 1,535 patients who were treated with chemotherapy alone, 1,015 relapsed. Half of them subsequently achieved a second complete remission. The overall survival was 30% at 3 years after relapse. Multivariate analysis showed that achievement of second complete remission, salvage allogeneic hematopoietic cell transplantation, and a relapse-free interval of 1 year or longer were independent prognostic factors. The outcome after allogeneic transplantation in second complete remission was comparable to that after transplantation in first complete remission. Patients with acute myeloid leukemia and cytogenetic risk factors other than inv(16) or t(8;21) had a significantly worse outcome when they did not undergo salvage transplantation even when they achieved second complete remission. Conclusions We found that both the achievement of second complete remission and the application of salvage transplantation were crucial for improving the prognosis of patients with acute myeloid leukemia in first relapse. Our results indicate that the optimal treatment strategy after first relapse may differ according to the cytogenetic risk.


Cancer Science | 2012

Central nervous system event in patients with diffuse large B-cell lymphoma in the rituximab era

Naoto Tomita; Masahiro Yokoyama; Wataru Yamamoto; Reina Watanabe; Yutaka Shimazu; Yasufumi Masaki; Saburo Tsunoda; Chizuko Hashimoto; Kayoko Murayama; Takahiro Yano; Rumiko Okamoto; Ako Kikuchi; Kazuo Tamura; Kazuya Sato; Kazutaka Sunami; Hirohiko Shibayama; Rishu Takimoto; Rika Ohshima; Yoshihiro Hatta; Yukiyoshi Moriuchi; Tomohiro Kinoshita; Masahide Yamamoto; Ayumi Numata; Yoshiaki Ishigatsubo; Kengo Takeuchi

Central nervous system (CNS) events, including CNS relapse and progression to CNS, are known to be serious complications in the clinical course of patients with lymphoma. This study aimed to evaluate the risk of CNS events in patients with diffuse large B‐cell lymphoma in the rituximab era. We performed a retrospective survey of Japanese patients diagnosed with diffuse large B‐cell lymphoma who underwent primary therapy with R‐CHOP chemoimmunotherapy between September 2003 and December 2006. Patients who had received any prophylactic CNS treatment were excluded. Clinical data from 1221 patients were collected from 47 institutions. The median age of patients was 64 years (range, 15–91 years). We noted 82 CNS events (6.7%) and the cumulative 5‐year probability of CNS events was 8.4%. Patients with a CNS event demonstrated significantly worse overall survival (P < 0.001). The 2‐year overall survival rate after a CNS event was 27.1%. In a multivariate analysis, involvement of breast (relative risk [RR] 10.5), adrenal gland (RR 4.6) and bone (RR 2.0) were identified as independent risk factors for CNS events. We conclude that patients with these risk factors, in addition to patients with testicular involvement in whom CNS prophylaxis has been already justified, are at high risk for CNS events in the rituximab era. The efficacy and manner of CNS prophylaxis in patients for each involvement site should be evaluated further. (Cancer Sci 2012; 103: 245–251)


Annals of Oncology | 2011

CD5-positive diffuse large B-cell lymphoma: a retrospective study in 337 patients treated by chemotherapy with or without rituximab

Kana Miyazaki; Motoko Yamaguchi; Ritsuro Suzuki; Yukio Kobayashi; Akiko Miyagi Maeshima; Nozomi Niitsu; D. Ennishi; Jun-ichi Tamaru; Kenichi Ishizawa; M. Kashimura; Yoshikazu Kagami; Kazutaka Sunami; H. Yamane; Momoko Nishikori; H. Kosugi; Toshiaki Yujiri; Rie Hyo; Naoyuki Katayama; Tomohiro Kinoshita; S. Nakamura

BACKGROUND CD5-positive (CD5+) diffuse large B-cell lymphoma (DLBCL) shows poor prognosis and frequent central nervous system (CNS) relapses under anthracycline-containing chemotherapy. The aim of this study was to determine the prognosis and CNS relapse incidence of CD5+ DLBCL in the rituximab era. PATIENTS AND METHODS We analyzed 337 patients with CD5+ DLBCL who received chemotherapy with (R-chemotherapy group; n = 184) or without (chemotherapy group; n = 153) rituximab. RESULTS No significant difference was found in clinical background comparisons between the two groups. In the R-chemotherapy group, 60% of the patients were older than 65 years at diagnosis. Both the complete response rate and overall survival (OS) were significantly better in the R-chemotherapy group (P = 0.0003 and P = 0.002, respectively). Multivariate analysis confirmed that chemotherapy without rituximab was associated with unfavorable OS. However, the probability of CNS relapse did not differ between the two groups (P = 0.89). The CNS relapse was strongly associated with short OS (P < 0.0001). In the R-chemotherapy group, 83% of patients who experienced CNS relapse had parenchymal disease. CONCLUSIONS Our results indicate that rituximab improves the OS of patients with CD5+ DLBCL but does not decrease the CNS relapse rate. More effective treatments with CNS prophylaxis are needed for CD5+ DLBCL patients.


Bone Marrow Transplantation | 2000

G-CSF reduces IFN-γ and IL-4 production by T cells after allogeneic stimulation by indirectly modulating monocyte function

Yuichiro Nawa; Takanori Teshima; Kazutaka Sunami; Yasushi Hiramatsu; Yoshinobu Maeda; Tomofumi Yano; Katsuji Shinagawa; Fumihiko Ishimaru; Eijiro Omoto; Mine Harada

Despite a 10-fold increase of T cell dose, the incidence and severity of acute GVHD following allogeneic transplantation of G-CSF-mobilized PBSC is not increased compared to BMT. Experimental murine studies demonstrate that G-CSF polarizes donor T cells toward a type 2 cytokine response. To determine whether G-CSF alters T cell cytokine responses, we investigated the effects of G-CSF administration on T cell proliferative and cytokine responses to alloantigen and Con A in nonadherent PBMC (NAC) and CD3+ T cells obtained from normal individuals before and after G-CSF administration (10 μg/kg × 4 days). Although T cell proliferative and cytokine (IFN-γ and IL-4) responses to alloantigen stimulation and Con A were significantly reduced in post-G-CSF NAC, they were restored by the removal of non-T cells from post-G-CSF NAC. Furthermore, there was less T cell alloreactivity in MLR in the presence of autologous post-G-CSF monocytes than in the presence of pre-G-CSF monocytes. This alteration was not replicated in vitro by culturing PBMC with G-CSF. These results suggest that G-CSF administration suppresses T cell proliferative and cytokine (IFN-γ and IL-4) responses to allogeneic stimulation by indirectly modulating monocyte function. Bone Marrow Transplantation (2000) 25, 1035–1040.


Bone Marrow Transplantation | 2001

Hepatic graft-versus-host disease presenting as an acute hepatitis after allogeneic peripheral blood stem cell transplantation

Nobuharu Fujii; Katsuto Takenaka; Katsuji Shinagawa; Kazuma Ikeda; Yoshinobu Maeda; Kazutaka Sunami; Yasushi Hiramatsu; Keitaro Matsuo; Fumihiko Ishimaru; Kenji Niiya; Tadashi Yoshino; Noriyuki Hirabayashi; Mine Harada

Hepatic graft-versus-host disease (GVHD) generally presents as cholestatic jaundice, and increased serum alkaline phosphatase (ALP) is followed by hyperbilirubinemia and clinical jaundice. Currently accepted standards for evaluating the clinical severity of GVHD are based not on serum aminotransferase levels but on the serum bilirubin level. We describe a 17-year-old Japanese female who had increased aminotransferases without cholestasis on day 23 after allogeneic peripheral blood stem cell transplantation (allo-PBSCT). Liver biopsy revealed lymphocytic infiltration of the portal tracts and pericentral necrosis of the lobuli. The limiting plates were not clearly defined due to cellular infiltrates. There was periductal lymphocytic infiltration and vacuolization of the biliary epithelial cells with exocytosis, compatible with GVHD of cholangiohepatitic type. These findings indicate that acute hepatic GVHD may present as acute hepatitis and this should be included in the differential diagnosis for patients with increased aminotransferases after allogeneic stem cell transplantation. Bone Marrow Transplantation (2001) 27, 1007–1010.


Blood | 2013

Phase 2 study of arsenic trioxide followed by autologous hematopoietic cell transplantation for relapsed acute promyelocytic leukemia

Masamitsu Yanada; Motohiro Tsuzuki; Hiroyuki Fujita; Katsumichi Fujimaki; Shin Fujisawa; Kazutaka Sunami; Masafumi Taniwaki; Akira Ohwada; Kosuke Tsuboi; Akio Maeda; Akihiro Takeshita; Shigeki Ohtake; Yasushi Miyazaki; Yoshiko Atsuta; Yukio Kobayashi; Tomoki Naoe; Nobuhiko Emi

The optimal treatments for relapsed acute promyelocytic leukemia (APL) remain equivocal. We conducted a phase 2 study to evaluate the efficacy and feasibility of a sequential treatment consisting of induction and consolidation with arsenic trioxide (ATO), peripheral blood stem cell (PBSC) harvest after high-dose cytarabine chemotherapy, and autologous hematopoietic cell transplantation (HCT). Between 2005 and 2009, 35 patients (26 with hematologic and 9 with molecular relapse) were enrolled. Induction therapy resulted in complete remission in 81% of those with hematologic relapse, and most patients became negative for PML-RARα after the first ATO consolidation course, but 4 remained positive. Administration of the second ATO consolidation course further decreased the transcript levels in 3 patients. In total, 25 patients proceeded to PBSC harvest, all of whom successfully achieved the target CD34+ cell doses, and 23 underwent autologous HCT with PML-RARα-negative PBSC graft. Posttransplant relapse occurred in 3 patients, and there was no transplant-related mortality. With a median follow-up of 4.9 years, the 5-year event-free and overall survival rates were 65% and 77%, respectively. These findings demonstrate the outstanding efficacy and feasibility of the sequential treatment featuring ATO and autologous HCT for relapsed APL. This study was registered at http://www.umin.ac.jp/ctr/ as #C000000302.


Leukemia & Lymphoma | 2001

High-dose Chemotherapy with Hematopoietic Stem Cell Transplantation is Effective for Nasal and Nasal-type CD56+ Natural Killer Cell Lymphomas

Katsuto Takenaka; Katsuji Shinagawa; Yoshinobu Maeda; Masanori Makita; Teruh ko Kozuka; Atsuko Ashiba; Kazuh ko Yamamoto; Nobuharu Fujii; Yuichiro Nawa; Yasushi Hiramatsu; Kazutaka Sunami; Fumihiko Ishimaru; Tadashi Yoshimo; Katsuyuki Kiura; Mine Harada

CD56+ natural killer (NK) cell lymphomas occur frequently in the nasal and nasopharyngeal regions and carry a poor prognosis. We have studied seven cases with NK-cell lymphomas. These lymphomas showed the following immunophenotype: CD56+, CD2+, sCD3 and Epstein-Barr virus-encoded small RNAs (EBERs)+. Six patients had localized (stage I or II) disease involving the nasopharyngeal region, while one had stage III disease. One patient with stage I disease achieved a complete remission (CR) after treatment with involved-field irradiation, but subsequently relapsed and died. The remaining six patients received combination chemotherapy as primary treatment: five patients with localized stage I or II disease and one patient with advanced stage III disease. Responses to initial chemotherapy were generally poor. These six patients received a variety of salvage chemotherapy regimens, but never achieved a CR. Subsequently, four of six patients showed a highly aggressive clinical course and died of disseminated disease within 1 year from the diagnosis. Three of six patients received high-dose chemotherapy supported by syngeneic, autologous or allogeneic peripheral blood stem cell transplantation. Two of the three transplant patients achieved a CR and are now surviving in continuous CR. Our clinical experience suggests that myeloablative high-dose chemotherapy and bone marrow rescue by hematopoietic stem cell transplantation may be an effective salvage treatment modality for refractory NK-cell lymphomas and could be considered as a part of the initial therapy for these patients.


Bone Marrow Transplantation | 2000

Allogeneic peripheral blood stem cell transplantation for the treatment of chronic active Epstein–Barr virus infection

Nobuharu Fujii; Katsuto Takenaka; Akio Hiraki; Yoshinobu Maeda; Kazuma Ikeda; Katsuji Shinagawa; Atsuko Ashiba; Mitsuru Munemasa; Kazutaka Sunami; Yasushi Hiramatsu; Fumihiko Ishimaru; Kenji Niiya; Tadashi Yoshino; Mine Harada

The prognosis of chronic active Epstein–Barr virus infection (CAEBV) is very poor. We describe a 24-year-old male with severe CAEBV who was treated with allogeneic peripheral blood stem cell transplantation (allo-PBSCT). On admission, EBER-1 in lymphocytes infiltrating the liver, EBV-DNA in peripheral blood mononuclear cells (PBMC) and monoclonal NK cell proliferation were confirmed. After unsuccessful chemotherapy, he received an allo-PBSCT from his HLA-identical sister. Although he died of pulmonary hemorrhage on day +19, EBV-DNA was undetectable by PCR in PBMC, and the post-mortem liver showed no EBER-1-positive lymphocytes. This experience suggests that EBV-positive lymphocytes in CAEBV may be eradicated by allo-PBSCT, thereby raising the possibility of a new treatment modality. Bone Marrow Transplantation (2000) 26, 805–808.

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Kenshi Suzuki

Memorial Hospital of South Bend

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