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Featured researches published by Jun-ichi Tamaru.


Blood | 2009

Age-related Epstein-Barr virus (EBV)-associated B-cell lymphoproliferative disorders: comparison with EBV-positive classic Hodgkin lymphoma in elderly patients.

Naoko Asano; Kazuhito Yamamoto; Jun-ichi Tamaru; Takashi Oyama; Fumihiro Ishida; Koichi Ohshima; Tadashi Yoshino; Naoya Nakamura; Shigeo Mori; Osamu Yoshie; Yoshie Shimoyama; Yasuo Morishima; Tomohiro Kinoshita; Shigeo Nakamura

Age-related Epstein-Barr virus-associated B-cell lymphoproliferative disorder (aEBVLPD) is a disease group characterized by EBV-associated large B-cell lymphoma in elderly without predisposing immunodeficiency. In nearly one- third of cases, aEBVLPD occurs as a polymorphous subtype with reactive cell-rich components, bearing a morphologic similarity to classic Hodgkin lymphoma (cHL). The aim of this study was to clarify clinicopathologic differences between the polymorphic subtype of aEBVLPD (n = 34) and EBV(+) cHL (n = 108) in patients aged 50 years or older. Results showed that aEBVLPD was more closely associated with aggressive clinical parameters than cHL, with a higher age at onset (71 vs 63 years); lower male predominance (male-female ratio, 1.4 vs 3.3); and a higher rate of involvement of the skin (18% vs 2%), gastrointestinal tract (15% vs 4%), and lung (12% vs 2%). aEBVLPD was histopathologically characterized by a higher ratio of geographic necrosis, greater increase (> 30%) in cytotoxic T cells among background lymphocytes, higher positivity for CD20 and EBNA2, and absence of CD15 expression. As predicted by the clinical profile, aEBVLPD had a significantly poorer prognosis than EBV(+) cHL (P < .001). The polymorphous subtype of aEBVLPD constitutes an aggressive group with an immune response distinct from EBV(+) cHL, and requires the development of innovative therapeutic strategies.


Haematologica | 2008

De novo CD5+ diffuse large B-cell lymphoma: results of a detailed clinicopathological review in 120 patients

Motoko Yamaguchi; Naoya Nakamura; Ritsuro Suzuki; Yoshitoyo Kagami; Masataka Okamoto; Ryo Ichinohasama; Tadashi Yoshino; Junji Suzumiya; Takuhei Murase; Ikuo Miura; Koichi Ohshima; Momoko Nishikori; Jun-ichi Tamaru; Masafumi Taniwaki; Masami Hirano; Yasuo Morishima; Ryuzo Ueda; Hiroshi Shiku; Shigeo Nakamura

Diffuse large B-cell lymphoma (DLBCL) constitutes the largest category of aggressive lymphomas, and is considered to have heterogeneous biological properties. De novo CD5-positive diffuse large B-cell lymphoma (CD5+ DLBCL) is a distinct entity. This study reveals the morphological spectrum of CD5+ DLBCL, shows that the incidence of central nervous system recurrence in this form of lymphoma in high, and confirms that CD5+ DLBCL frequently expresses BCL2 protein. Background De novo CD5-positive diffuse large B-cell lymphoma (CD5+ DLBCL) is clinicopathologically and genetically distinct from CD5-negative (CD5−) DLBCL and mantle cell lymphoma. The aim of this retrospective study was to clarify the histopathological spectrum and obtain new information on the therapeutic implications of CD5+ DLBCL. Design and Method From 1984 to 2002, 120 patients with CD5+ DLBCL were selected from 13 collaborating institutes. We analyzed the relationship between their morphological features and long-term survival. The current series includes 101 patients described in our previous study. Results Four morphological variants were identified: common (monomorphic) (n=91), giant cell-rich (n=13), polymorphic (n=14), and immunoblastic (n=2). Intravascular or sinusoidal infiltration was seen in 38% of the cases. BCL2 protein expression in CD5+ DLBCL was more frequent than in CD5− DLBCL (p=0.0003). Immunohistochemical analysis in 44 consecutive cases of CD5+ DLBCL revealed that 82% of these cases (36/44) were non-germinal center B-cell type DLBCL. The 5-year overall survival rate of the patients with CD5+ DLBCL was 38% after a median observation time of 81 months. Patients with the common variant showed a better prognosis than those with the other three variants (p=0.011), and this was confirmed on multivariate analysis. Overall, 16 patients (13%) developed central nervous system recurrence. Conclusions Our study revealed the morphological spectrum of CD5+ DLBCL, found that the incidence of central nervous system recurrence in this form of lymphoma in high, confirmed that CD5+ DLBCL frequently expresses BCL2 protein and showed that it is mainly included in the non-germinal center B-cell type of DLBCL.


Modern Pathology | 2002

The Distinction between Burkitt Lymphoma and Diffuse Large B-Cell Lymphoma with c- myc Rearrangement

Naoya Nakamura; Hirokazu Nakamine; Jun-ichi Tamaru; Shigeo Nakamura; Tadashi Yoshino; K. Ohshima; Masafumi Abe

To compare immunophenotypic and molecular features between Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) with c-myc rearrangements (c-mycR DLBCL), we analyzed 18 cases of B-cell non-Hodgkins lymphoma with c-mycR that were confirmed by chromosomal and/or Southern blotting analyses. The cases were histologically classified into 10 BLs and five DLBCLs. The remaining three cases could not be classified because of suboptimal quality of the surgical materials. BLs were from five adults and five children, whereas all DLBCLs were from adults. BLs were positive for CD20 (10/10 cases examined), CD10 (9/10), Bcl-2 (1/9), and Bcl-6 (10/10), whereas they were negative for CD3 (0/10) and EBV (0/8), by Epstein-Barr virus (EBV) EBER-1 RNA in situ hybridization. c-MycR DLBCLs were positive for CD20 (5/5), CD10 (2/5), Bcl-2 (3/4), and Bcl-6 (4/4), whereas none of them were positive for CD3 and EBV. A mean of MIB-1 index (MIB-1+ cells/neoplastic cells, %) of BLs (98.1%) was higher than that of c-mycR DLBCLs (66.3%; P < .0001). Somatic mutation of immunoglobulin heavy-chain gene variable region (VH gene) in BLs (four cases) ranged from 0.7 to 4.9% with an average value of 2.3%, whereas those in DLBCLs (three cases) from 8.2 to 32.0% with an average value of 17.0%. It is, therefore, concluded that a growth fraction of nearly 100%, as well as a monotonous proliferation of medium-sized cells and c-mycR, should be of value in the diagnosis of BL, which is probably different from c-mycR DLBCL. In addition, CD10+, Bcl-2−, and low frequency of mutation of the VH gene could be helpful for the histologic distinction of BL from (c-mycR) DLBCL.


European Journal of Haematology | 2002

Simultaneous elevation of the serum concentrations of vascular endothelial growth factor and interleukin‐6 as independent predictors of prognosis in aggressive non‐Hodgkin's lymphoma

Nozomi Niitsu; Masataka Okamoto; Hirokazu Nakamine; Tadashi Yoshino; Jun-ichi Tamaru; Shigeo Nakamura; Masaaki Higashihara; Masami Hirano

Abstract: Therapeutic approaches for non‐Hodgkins lymphoma (NHL) are currently based on the International Prognostic Index (IPI). Research on biological prognostic factors has been actively pursued in recent years, with serum vascular endothelial growth factor (VEGF) and interleukin‐6 (IL‐6) being identified as prognostic factors for NHL. Here, we determined that serum VEGF and IL‐6 levels are independent prognostic factors for aggressive lymphoma. Compared with normal controls, serum VEGF and IL‐6 levels were significantly higher in patients with aggressive lymphoma or adult T‐cell leukemia/lymphoma. Furthermore, overall and disease‐free survival rates for patients with high levels of VEGF or IL‐6 were significantly poorer than for patients with low levels. In addition, the prognosis for patients with high levels of both serum VEGF and IL‐6 was significantly poorer than that for patients with high levels of either VEGF or IL‐6 or with low levels of both VEGF and IL‐6. Multivariate analyses of a variety of prognostic factors, including the five IPI factors, revealed that serum VEGF and IL‐6 were both independent prognostic factors for overall survival of aggressive lymphoma. Therefore, a combination of VEGF and IL‐6 represents a useful prognostic factor for aggressive lymphoma.


Journal of Clinical Oncology | 2006

Prognostic Significance of T-Cell or Cytotoxic Molecules Phenotype in Classical Hodgkin’s Lymphoma: A Clinicopathologic Study

Naoko Asano; Aya Oshiro; Keitaro Matsuo; Yoshitoyo Kagami; Fumihiro Ishida; Ritsuro Suzuki; Tomohiro Kinoshita; Yoshie Shimoyama; Jun-ichi Tamaru; Tadashi Yoshino; Kunio Kitamura; Hisashi Fukutani; Yasuo Morishima; Shigeo Nakamura

PURPOSE Classical Hodgkins lymphoma (CHL) is characterized by Hodgkins and Reed-Sternberg (H-RS) cells, most of which are derived from germinal-center B cells. Nevertheless, one or more markers for T cells and follicular dendritic cells (FDC) may be expressed in a minority of H-RS cells in some CHL patients, although the clinical significance of this remains controversial. The aim of this study was to clarify the association between phenotypic expression and clinical outcome in CHL. PATIENTS AND METHODS Participants were 324 consecutive CHL patients, comprising 132 patients with nodular sclerosis (NS), 35 patients with NS grade 2 (NS2), and 157 patients with mixed cellularity (MC). We evaluated the presenting features and prognosis of patients on categorization into four phenotypically defined groups: B-cell (CD20+ and/or CD79a+; n = 63), T-cell and/or cytotoxic molecules (CD3+, CD4+, CD8+, CD45RO+, TIA-1+, and/or granzyme B+; n = 27), FDC (CD21+ without B-cell marker; n = 22), and null-cell types (n = 212). Other potential prognostic factors were examined. RESULTS The T-cell and/or cytotoxic molecules group showed a significantly poorer prognosis than the other three groups (P < .0001). This finding was seen consistently in multivariate analyses. Morphologic subtyping (NS/NS2/MC) and Epstein-Barr virus positivity were not identified as independent prognostic factors. CONCLUSION The presence of T-cell and/or cytotoxic antigens in H-RS cells may represent a poor prognostic factor in CHL, even if their expression is not regarded as lineage specific. Examination of T-cell and/or cytotoxic molecules phenotype in CHL patients is recommended as a routine pathologic practice.


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.


Virchows Archiv | 2005

Immunophenotype of lymphocytic infiltration in medullary carcinoma of the breast

Hajime Kuroda; Jun-ichi Tamaru; Goi Sakamoto; Kiyoshi Ohnisi; Shinji Itoyama

Medullary carcinoma (MC) of the breast is characterized by large anaplastic cells and infiltration by benign lymphocytes. Patients with this pattern of breast carcinoma are considered to have a better prognosis than those with other histological subtypes. We reviewed cases of primary breast carcinoma that were surgically resected between 1990 and 2004. Of these, 13 cases of medullary carcinoma of the breast with lymphocyte infiltration were reported. Tests for CD3, CD4, CD8, CD20, CD56, TIA-1, and granzyme B were performed on paraffin sections. We found that the MC contained very few NK cells, as assessed by their reactivity with the CD56 antibodies. However, MC had a significantly greater percentage of CD3, CD8, TIA-1, and granzyme B lymphocytes infiltrating the stroma of the tumor. Furthermore, more CD8-positive than CD4-positive T-cell lymphocytes were present within the tumor cell nests in MC, as opposed to the proportion in usual ductal carcinoma. The infiltrating cytotoxic/suppressor T cells in MC represent host resistance against cancer, and the high grading of the T-cell infiltration could explain, in part, a key mechanism controlling the good prognosis for this type of tumor and solve the pathological paradox of MC.


Pathology International | 2001

Morphological spectrum of cyclin D1-positive mantle cell lymphoma: study of 168 cases.

Yasushi Yatabe; Ritsuro Suzuki; Yoshihiro Matsuno; Kensei Tobinai; Ryo Ichinohazama; Jun-ichi Tamaru; Yoshikazu Mizoguchi; Yuko Hashimoto; Motoko Yamaguchi; Masaru Kojima; Naokuni Uike; Masataka Okamoto; Kotaro Isoda; Koichi Ichimura; Yasuo Morishima; Masao Seto; Taizan Suchi; Shigeo Nakamura

Immunostaining for cyclin D1 is essential for reliable diagnosis of mantle cell lymphoma (MCL). However, a small number of cyclin D1‐positive lymphomas other than MCL have been encountered. Our goal was to investigate the morphological spectrum of MCL as a disease entity, based on cyclin D1 overexpression. We reviewed 181 biopsy specimens obtained from 168 cases of cyclin D1‐positive MCL. Typical findings were the presence of nodular (53.9% of cases) or diffuse (46.1%) histological patterns, containing mantle zone patterns (16.8%), naked germinal centers (33.5%) and perivascular hyaline deposition (83.2%). Unusual findings of residual germinal centers with a mantle cuff (four cases) and follicular colonization (two cases) were seen. High magnification showed a monotonous proliferation of tumor cells with cytological diversity including small (3.0%), intermediate (43.1%), medium (34.1%), medium– large (13.2%) and large (6.6%) cells. Pleomorphic and blastic / blastoid variants were encountered in 9.6 and 7.2% of cases, respectively. Three cases had foci of cells of considerable size, with a moderately abundant pale cytoplasm resembling marginal zone B cells. Two cases showed an admixture of cells which appeared transformed and mimicked the histology of chronic lymphocytic leukemia / small lymphocytic leukemia. In one, neoplastic mantle zones were surrounded by sheets of mature plasma cells, resembling the plasma cell type of Castleman’s disease. An admixture of areas characteristic of MCL and of other larger cells, indicating histological progression or a composite lymphoma, were observed in seven cases. In high‐grade lesions of five cases, nuclear staining of cyclin D1 was rarely detected. In our experience, cyclin D1 expression was also found in nine lymphomas other than MCL (five plasma cell myelomas, three Hodgkin’s disease and one anaplastic large cell lymphoma). The application of cyclin D1 staining prompted us to recognize the broad morphological spectrum of MCL. MCL can be diagnosed with the application of cyclin D1 immunostaining, if careful attention is given to architectural and cytological features.


European Journal of Haematology | 2002

Beneficial effects of rituximab on primary cold agglutinin disease refractory to conventional therapy.

Akinori Mori; Jun-ichi Tamaru; Hajime Sumi; Haruki Kondo

Abstract: A case is reported of lymphoplasmacytoid lymphoma (LPL) associated with a monoclonal immunoglobulin (Ig) M and cold agglutinin disease (CAD) that was successfully treated with rituximab. A 52‐yr‐old male was admitted with a direct antiglobulin test positive haemolytic anaemia and thrombocytopenia associated with monoclonal IgM. Bone marrow examinations disclosed the marked infiltration of medium‐sized lymphoma cells with plasmacytoid differentiation that indicated non‐Hodgkins lymphoma of B‐cell origin (LPL). Prednisolone and combination chemotherapy were temporarily effective for both anaemia and thrombocytopenia, although these strategies became refractory and bone marrow lymphoplasmacytosis persisted. CAD ameliorated, and the serum level of IgM decreased in association with the disappearance of lymphoma cells and clonal rearrangement of the Ig heavy chains in the bone marrow after treatment with rituximab. Rituximab played a significant role in the treatment of refractory CAD associated with LPL.


Clinical Cancer Research | 2012

Expression of Epstein-Barr Virus–Encoded Proteins in Extranodal NK/T-cell Lymphoma, Nasal Type (ENKL): Differences in Biologic and Clinical Behaviors of LMP1-Positive and -Negative ENKL

Naoko Kanemitsu; Yasushi Isobe; Azuchi Masuda; Shuji Momose; Morihiro Higashi; Jun-ichi Tamaru; Koichi Sugimoto; Norio Komatsu

Purpose: Extranodal NK/T-cell lymphoma, nasal type (ENKL) is closely associated with Epstein-Barr virus (EBV). To elucidate its pathogenetic role, we examined the expression profiles of EBV-encoded proteins, especially focusing on latent membrane protein 1 (LMP1). Experimental Design: Immunohistochemistry was carried out using clinical samples from ENKL cases, which were diagnosed between 1996 and 2010 at our institution. We statistically assessed the correlation between LMP1 positivity and the clinicopathologic data and further examined phosphorylation status of NF-κB RelA and Akt in ENKL cell lines. Results: Most of the 30 examined cases showed pleomorphic morphology, natural killer cell immunophenotype, and a localized disease. Immunohistochemistry detected EBERs, but not EBNA2, in all cases. LMP1 and LMP2A were positive in 22 (73.3%) and 12 cases (40.0%), respectively. LMP1-positive cases tended to show a localized disease (P = 0.060, the Fisher exact test). Nuclear localization of phosphorylated RelA and detection of phosphorylated Akt were predominantly observed in LMP1-positive cases (P = 0.002 and P < 0.001, respectively, the Fisher exact test). RNA silencing experiments of LMP1 in Hank1 cells suggested a positive correlation between LMP1 expression and phosphorylation of RelA and Akt. With a median follow-up period of 26.7 months (range, 0.2–142.3 months), the 2.5-year overall survival rates for LMP1-positive and -negative cases were estimated at 78.3% and 12.5%, respectively (P = 0.001, log-rank test). Conclusions: LMP1 expression shows correlations with phosphorylation of RelA and Akt and possibly has a favorable impact on clinical outcome in ENKL. Clin Cancer Res; 18(8); 2164–72. ©2012 AACR.

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Morihiro Higashi

Saitama Medical University

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Hideyuki Ishida

Saitama Medical University

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Nozomi Niitsu

Saitama Medical University

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Shinji Itoyama

Saitama Medical University

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Kensuke Kumamoto

Fukushima Medical University

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