Rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone combined with high-dose methotrexate plus intrathecal chemotherapy for newly diagnosed intravascular large B-cell lymphoma (PRIMEUR-IVL): a multicentre, single-arm, phase 2 trial.

BACKGROUND: Intravascular large B-cell lymphoma (IVLBCL) is a rare disease for which there is no available standard treatment. We aimed to ascertain the safety and activity of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone) with high-dose methotrexate and intrathecal chemotherapy as CNS-oriented therapy for patients with previously untreated IVLBCL. METHODS: PRIMEUR-IVL is a multicentre, single-arm, phase 2 trial at 22 hospitals in Japan. Eligible patients had untreated histologically confirmed IVLBCL, were aged 20-79 years, had an Eastern Cooperative Group performance status of 0-3, and had no apparent CNS involvement at diagnosis. Patients received three cycles of R-CHOP (rituximab 375 mg/m2 intravenously on day 1 [except cycle one, which was on day 8]; cyclophosphamide 750 mg/m2, doxorubicin 50 mg/m2, and vincristine 1·4 mg/m2 [maximum 2·0 mg] intravenously on day 1 of cycle one and day 2 of cycles two and three; and prednisolone 100 mg/day orally on days 1-5 of cycle one and days 2-6 of cycles two and three) followed by two cycles of rituximab with high-dose methotrexate (3·5 g/m2 intravenously on day 2 of cycles four and five) every 2 weeks and three additional cycles of R-CHOP. Intrathecal chemotherapy (methotrexate 15 mg, cytarabine 40 mg, and prednisolone 10 mg) was administered four times during the R-CHOP phase. The primary endpoint was 2-year progression-free survival. Efficacy analyses were done in all enrolled patients; safety analyses were done in all enrolled and treated patients. The trial is registered in the UMIN Clinical Trials Registry (UMIN000005707) and the Japan Registry of Clinical Trials (jRCTs041180165); the trial is ongoing for long-term follow-up. FINDINGS: Between June 16, 2011, and July 21, 2016, 38 patients were enrolled, of whom 37 were eligible; one patient was excluded because of a history of testicular lymphoma. Median follow-up was 3·9 years (IQR 2·5-5·5). 2-year progression-free survival was 76% (95% CI 58-87). The most frequent adverse events of grade 3-4 were neutropenia and leucocytopenia, which were reported in all 38 (100%) patients. Serious adverse events were hypokalaemia, febrile neutropenia with hypotension, hypertension, and intracerebral haemorrhage (reported in one [3%] patient each). No treatment-related deaths occurred during protocol treatment. INTERPRETATION: R-CHOP combined with rituximab and high-dose methotrexate plus intrathecal chemotherapy is a safe and active treatment for patients with IVLBCL without apparent CNS involvement at diagnosis, and this regimen warrants future investigation. FUNDING: The Japan Agency for Medical Research and Development, the Center for Supporting Hematology-Oncology Trials, and the National Cancer Center.

Improved prognosis of extranodal NK/T cell lymphoma, nasal type of nasal origin but not extranasal origin.

Extranodal NK/T cell lymphoma (NKTCL), nasal type (ENKL) that shows no apparent nasal involvement, is termed extranasal NKTCL or non-nasal NKTCL. In this study, we aimed to explore therapeutic approaches and outcomes in patients with extranasal NKTCL in current clinical practice. A data set of patients with newly diagnosed NKTCL who were diagnosed at 31 institutes in Japan between 2000 and 2013 was used for analysis. The patients' fitness for steroid, methotrexate, ifosfamide, L-asparaginase, and etoposide (SMILE) chemotherapy was assessed using the major inclusion criteria of the SMILE phase 2 study. Of 358 patients, 47 (13%) had extranasal NKTCL. The most frequent extranodal sites of involvement in extranasal NKTCL were skin/subcutaneous tissue (n = 18). Six (13%) of the patients with extranasal NKTCL had localized disease and were diagnosed before 2010. With a median follow-up of 5.8 years, the 2-year overall survival (OS) in patients with nasal and extranasal NKTCL was 70% (95% confidence interval [CI], 65-75%) and 34% (95% CI, 21-47%), respectively. OS in patients with nasal NKTCL had a trend toward better according to treatment era (P = 0.063). In contrast, no obvious improvement of OS was observed in extranasal NKTCL (P = 0.43). The major inclusion criteria of the SMILE-P2 were met in 21% (10/47) of patients with extranasal NKTCL and 60% (188/311) of those with nasal NKTCL (P < 0.001). Despite the advent of new treatments for ENKL, OS remains unfavorable in extranasal NKTCL. A more effective therapy is needed for extranasal NKTCL.

Prognostic significance of metabolic tumor burden by positron emission tomography/computed tomography in patients with relapsed/refractory diffuse large B-cell lymphoma.

The aim of the present study was to investigate the feasibility of measuring metabolic tumor burden using [F-18] fluorodeoxyglucose ((18) F-FDG) positron emission tomography/computed tomography (PET/CT) in patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) treated with bendamustine-rituximab. Because the standardized uptake value is a critical parameter of tumor characterization, we carried out a phantom study of (18) F-FDG PET/CT to ensure quality control for 28 machines in the 24 institutions (Japan, 17 institutions; Korea, 7 institutions) participating in our clinical study. Fifty-five patients with relapsed or refractory DLBCL were enrolled. The (18) F-FDG PET/CT was acquired before treatment, after two cycles, and after the last treatment cycle. Treatment response was assessed after two cycles and after the last cycle using the Lugano classification. Using this classification, remission was complete in 15 patients (27%) and incomplete in 40 patients (73%) after two cycles of therapy, and remission was complete in 32 patients (58%) and incomplete in 23 patients (42%) after the last treatment cycle. The percentage change in all PET/CT parameters except for the area under the curve of the cumulative standardized uptake value-volume histogram was significantly greater in complete response patients than in non-complete response patients after two cycles and the last cycle. The Cox proportional hazard model and best subset selection method revealed that the percentage change of the sum of total lesion glycolysis after the last cycle (relative risk, 5.24; P = 0.003) was an independent predictor of progression-free survival. The percent change of sum of total lesion glycolysis, calculated from PET/CT, can be used to quantify the response to treatment and can predict progression-free survival after the last treatment cycle in patients with relapsed or refractory DLBCL treated with bendamustine-rituximab.

Prognostic significance of pleural or pericardial effusion and the implication of optimal treatment in primary mediastinal large B-cell lymphoma: a multicenter retrospective study in Japan.

The prognosis of patients with primary mediastinal large B-cell lymphoma has improved over recent years. However, the optimal treatment strategy including the role of radiotherapy remains unknown. We retrospectively analyzed the clinical outcomes of 345 patients with newly diagnosed primary mediastinal large B-cell lymphoma in Japan. With a median follow up of 48 months, the overall survival at four years for patients treated with R-CHOP (n=187), CHOP (n=44), DA-EPOCH-R (n=9), 2(nd)- or 3(rd)-generation regimens, and chemotherapy followed by autologous stem cell transplantation were 90%, 67%, 100%, 91% and 92%, respectively. Focusing on patients treated with R-CHOP, a higher International Prognostic Index score and the presence of pleural or pericardial effusion were identified as adverse prognostic factors for overall survival in patients treated with R-CHOP without consolidative radiotherapy (IPI: hazard ratio 4.23, 95% confidence interval 1.48-12.13, P=0.007; effusion: hazard ratio 4.93, 95% confidence interval 1.37-17.69, P=0.015). Combined with the International Prognostic Index score and the presence of pleural or pericardial effusion for the stratification of patients treated with R-CHOP without radiotherapy, patients with lower International Prognostic Index score and the absence of effusion comprised approximately one-half of these patients and could be identified as curable patients (95% overall survival at 4 years). The DA-EPOCH-R regimen might overcome the effect of these adverse prognostic factors. Our simple indicators of International Prognostic Index score and the presence of pleural or pericardial effusion could stratify patients with primary mediastinal large B-cell lymphoma and help guide selection of treatment.

[Targeted therapy].

Rituximab, a genetically engineered chimeric monoclonal antibody that specifically binds to CD20, is the first monoclonal antibody approved for the treatment of B-cell lymphoma. It has been shown that rituximab exerts cytotoxic activities through CDC and ADCC, and that it directly induces apoptosis. The CD20 protein has four transmembrane domains (tetraspan structure) and is not internalized following antibody binding, and is not shed or secreted into the circulation. Therefore, CD20 can serve as a target of antibody therapy. As the other anti-CD20 antibodies, there are ofatumumab and obinutuzumab, and clinical development is expected. In addition, histone deacetylate inhibitor or proteasome inhibitor as a new drugs for lymphoma in the future.

Incidence and clinical significance of aberrant T-cell marker expression on diffuse large B-cell lymphoma cells.

INTRODUCTION: Aberrant expression of T-cell markers is occasionally observed in B-cell lymphomas. We conducted a retrospective study to establish its incidence and to determine its relationship with clinical features of patients with diffuse large B-cell lymphoma (DLBCL). PATIENTS AND METHODS: We reviewed DLBCL patients diagnosed between January 2002 and April 2009. Patients fulfilled the following criteria: (1) age >18 years, (2) HIV negative, (3) B-cell lymphoma confirmed by restricted expression of surface immunoglobulin light chains by flow cytometry (FCM). Aberrant T-cell marker expression (ATCME) was defined as positivity for CD2, CD3, CD4, CD7, and/or CD8 on DLBCL cells by FCM. Phenotyping was also performed by immunohistochemistry (IHC). Patients were grouped according to positive or negative ATCME and their clinical features including survival were compared. RESULTS: Of 150 patients, 11 (7.3%) showed ATCME; CD2 and CD7 were most often expressed. ATCME was less often detected and the signal was weaker using IHC. There were no statistically significant differences in clinical features between the two groups. CONCLUSIONS: FCM may be useful to detect ATCME in a small amount of lymphoma cells. The mechanism responsible for ATCME, and whether it contributes in any way to the pathogenesis of B-cell neoplastic transformation, requires clarification.

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.

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.

Association of CD20 levels with clinicopathological parameters and its prognostic significance for patients with DLBCL.

Diffuse large B-cell lymphomas (DLBCL) express CD20. CD20 expression is described as negative, weak, or normal as determined by flow cytometry (FCM) and is an important target for the treatment of DLBCL. However, the impact of CD20 levels at onset of the disease on patient prognosis has not been fully elucidated. We analyzed 174 DLBCL cases newly diagnosed between January 1998 and April 2010. The relationship of the association between CD20 levels and patients' backgrounds and prognoses was analyzed using the Kaplan-Meier method and Cox proportional hazard regression. Of the 174 patients, three cases (1.7%) were defined as CD20 negative based on immunohistochemistry (IHC). Although the other 171 cases were positive by IHC, eight cases (4.7%) were defined as negative and 33 cases (19.3%) were defined as weak when analyzed by FCM. Of the 105 patients who received rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisolone therapy, those who were CD20 negative (FCM) showed significantly inferior overall (hazard ratios (HR): 6.79, 95% CI: 1.32-34.96, p = 0.04) and progression-free survival (HR: 7.3, 95% CI: 1.49-35.8, p = 0.04) compared to patients who were CD20 normal. Our findings indicate that the CD20 level (FCM) at onset is an independent predictor of the prognosis of patients with DLBCL.

Multicentre phase II study of the CyclOBEAP regimen for patients with peripheral T-cell lymphoma with analysis of biomarkers.

Peripheral T-cell lymphoma (PTCL) has a poorer prognosis than diffuse large B-cell lymphoma (DLBCL). We administered the CyclOBEAP regimen (cyclophosphamide, vincristine, bleomycin, etoposide, doxorubicin, prednisolone) to patients with DLBCL, and reported its safety and efficacy. Here, we report the results of a multicentre phase II study of the CyclOBEAP regimen in patients with PTCL. In addition, NME1 remained a prognostic factor for survival, as shown in patients who were treated with CyclOBEAP. There were 84 eligible patients and the median age was 54 years. The 5-year overall survival (OS) rate was 72% and progression-free survival (PFS) rate was 61%. The 5-year OS was 93% among the anaplastic large-cell lymphoma cases, 74% among the angioimmunoblastic T-cell lymphoma cases, and 63% among the cases of PTCL-not otherwise specified. When the patients were divided according to the International Prognostic Index or Prognostic Index for PTCL, the 5-year OS and PFS rates did not significantly differ among the risk groups. Positivity for NME1 was found to be a significant independent prognostic factor. Grade 4 neutropenia was observed in 80 patients and thrombocytopenia in nine patients. Our results suggest that the CyclOBEAP therapy is safe and effective for PTCLs. Furthermore, the NME1 protein may be an important prognostic factor in PTCL.

Cytotoxic molecule-positive classical Hodgkin's lymphoma: a clinicopathological comparison with cytotoxic molecule-positive peripheral T-cell lymphoma of not otherwise specified type.

BACKGROUND: Classical Hodgkin's lymphoma is characterized by Hodgkin and Reed Sternberg cells, which are of B-cell origin in many cases. We recently highlighted the adverse prognostic significance of cytotoxic molecule expression in patients with classical Hodgkin's lymphoma. However, the clinical characteristics of cytotoxic molecule-positive classical Hodgkin's lymphoma remain controversial. DESIGN AND METHODS: We investigated the clinicopathological profiles of 32 patients with cytotoxic molecule-positive Hodgkin's lymphoma, comprising 23 with nodular sclerosis and 9 with mixed cellularity, and compared these profiles with those of 55 patients with cytotoxic molecule-positive nodal peripheral T-cell lymphoma, not otherwise specified and 439 patients with cytotoxic molecule-negative Hodgkin's lymphoma. RESULTS: The patients with cytotoxic molecule-positive Hodgkin's lymphoma consisted of 20 men and 12 women with a median age of 50 years (range, 19 to 81). All these patients had lymphadenopathy at presentation, and 14 showed mediastinal involvement. Physical findings included hepatomegaly and splenomegaly in six patients each. Four patients had a bulky mass, and nine showed stage IV disease. The tumor cells of patients with cytotoxic molecule-positive Hodgkin's lymphoma had a prototypic immunophenotype of CD15(+) CD30(+) CD45RO(-) fascin(+), with positivity for Epstein-Barr virus in 39% of cases. All patients were negative for Pax5. In comparison with patients with cytotoxic molecule-positive nodal peripheral T-cell lymphomas, not otherwise specified, patients with cytotoxic-positive Hodgkin's lymphoma had relatively mild clinical symptoms, similar to those of patients with cytotoxic molecule-negative Hodgkin's lymphoma. Regarding prognosis, the survival of patients with cytotoxic molecule-positive Hodgkin's lymphoma was worse than that of patients with cytotoxic molecule-negative Hodgkin's lymphoma (P = 0.0003) but better than that of patients with cytotoxic molecule-positive peripheral T-cell lymphomas, not otherwise specified (P = 0.002). CONCLUSIONS: Cytotoxic molecule-positive Hodgkin's lymphoma is characterized by an unfavorable prognosis, even if its clinicopathological features are within the boundaries of classical Hodgkin's lymphoma. More effective chemotherapy for cytotoxic molecule-positive Hodgkin's lymphoma is clearly required.

A study on nm23-H1 expression in diffuse large B-cell lymphoma that was treated with CyclOBEAP plus rituximab therapy.

In our previous study on nm23-H1 expression with diffuse large B-cell lymphoma (DLBCL), we found that patients with positive nm23-H1 had significantly poorer prognosis than patients with negative nm23-H1. We examined whether nm23-H1 is a prognostic factor of DLBCL in the rituximab era. The subjects were 101 DLBCL patients who underwent R-CyclOBEAP (rituximab, cyclophosphamide, vincristine, bleomycin, etoposide, doxorubicin, and prednisolone) therapy and in whom markers could be analyzed. We evaluated CD5, CD10, BCL2, BCL6, MUM1, and nm23-H1 expression by immunohistochemistry. Ninety-four DLBCL patients who underwent CyclOBEAP therapy were assumed as historical controls. Among DLBCL patients who underwent CyclOBEAP therapy, BCL2 positivity, MUM1 positivity, non-germinal center B-cell (non-GCB), and nm23-H1 positivity were associated with significantly shorter overall survival (OS) and progression-free survival (PFS). On the other hand, among DLBCL patients who underwent R-CyclOBEAP therapy, the 5-year OS rates of the nm23-H1-positive DLBCL (n = 32) and nm23-H1-negative DLBCL groups (n = 69) were 65% and 97%, respectively (p = 0.001), with 5-year PFS rates of 51% and 89%, respectively (p = 0.001). In the rituximab era, BCL2, MUM1, and non-GCB were not prognostic factors. We demonstrated that among patients with DLBCL who underwent R-CyclOBEAP therapy, patients with nm23-H1 expression had a significantly poorer prognosis than patients without nm23-H1 expression. These results suggest an important role for nm23-H1 in malignant progression and a potential therapeutic target for DLBCL.

Clinicopathologic correlations of diffuse large B-cell lymphoma in rheumatoid arthritis patients treated with methotrexate.

Among methotrexate (MTX)-related lymphoproliferative disorders (MTX-LPD), diffuse large B-cell lymphoma (DLBCL) accounts for about half. We studied the clinicopathological characteristics and prognosis of patients with DLBCL in MTX-LPD. This study included 29 patients who developed DLBCL after receiving MTX for rheumatoid arthritis. MTX was discontinued in all patients. Their median age was 62 years. Elevated lactate dehydrogenase (LDH) level was observed in 97% of the patients, bone marrow involvement in 17%, and involvement of extranodal sites in 41%. As for the cellular immunophenotype, CD20 was positive in 93%, CD5 in 3%, CD10 in 31%, BCL2 in 21%, BCL6 in 69%, and Epstein-Barr virus (EBV)-encoded small non-polyadenylated RNA (EBER) in 24%. Chemotherapy was started within 2 months after MTX withdrawal in 23 patients, of whom 12 patients received combination with rituximab. Spontaneous remission occurred in the remaining six patients. The EEBV-positive rate was 67% (4/6), and the four EBV-positive patients achieved complete response. Among the 23 DLBCL patients treated with chemotherapy, 20 patients achieved complete response. The 5-year overall survival was 74% and the 5-year progression-free survival was 65%. After the development of DLBCL, withdrawal of MTX was the first choice of treatment. Germinal center B-cell type and EBER-positive patients tended to show spontaneous remission. The utility of rituximab should be examined in future studies.

Central nervous system involvement in intravascular large B-cell lymphoma: a retrospective analysis of 109 patients.

Intravascular large B-cell lymphoma (IVLBCL) is a rare disease entity with a high incidence of central nervous system (CNS) involvement at diagnosis. To evaluate CNS involvement, particularly recurrence including progression on therapy and relapse of IVLBCL, we retrospectively analyzed 109 patients with IVLBCL receiving chemotherapies with or without rituximab. In 82 patients (75%) without CNS involvement at initial diagnosis, risk of CNS recurrence at 3 years was 25% with a median follow-up in survivors of 39 months (range, 2-158 months). In 27 patients (25%) with CNS involvement at initial diagnosis, risk of CNS recurrence at 1 year was 25% with a median follow-up in survivors of 18 months (range, 10-77 months). Duration from diagnosis to CNS recurrence tended to be short in patients with CNS involvement at diagnosis. No significant difference in risk of CNS recurrence was found between patients receiving chemotherapies with or without rituximab. On multivariate analysis skin involvement at initial diagnosis was identified as a predictive factor for CNS recurrence in patients without CNS involvement at diagnosis (hazard ratio, 5.27; 95% confidence interval, 1.59-17.4; P = 0.007). Survival rate after CNS recurrence at 2 years was 12% in patients without CNS involvement at diagnosis. Central nervous system recurrence is a serious complication in IVLBCL patients and optimal strategies for CNS involvement should be established to obtain further improvements to clinical outcomes in the rituximab era.

Multicentre phase II study of CyclOBEAP plus rituximab in patients with diffuse large B-cell lymphoma.

The R-CHOP regimen has been found to improve the outcome of diffuse large B-cell lymphoma (DLBCL). However, it does not provide a satisfactory treatment outcome in the high-risk group. We previously administered the CyclOBEAP regimen to patients with DLBCL, and reported its safety and efficacy. The R-CyclOBEAP regimen was administered over a total period of 12 weeks, and rituximab 375 mg/m(2) was given every 2 weeks. There were 101 eligible patients. CR was achieved in 96 patients (95%). The 5-year overall survival (OS) rate was 85% and progression-free survival (PFS) rate was 76%. When the patients were divided according to the IPI, the 5-year OS and PFS rates did not significantly differ among the risk groups. The 5-year PFS of the germinal centre B-cell group was 80% and that of the non-GCB group was 74% (NS). Univariate analysis showed that the presence of B symptoms, extranodal lesions >or=2, and sIL-2R were significant poor prognostic factors. Grade 4 neutropenia was observed in 91 patients and thrombocytopenia in 9 patients. The addition of rituximab to CyclOBEAP therapy may enhance the effect of CyclOBEAP therapy for DLBCL.

[Marfan syndrome complicated with CD5+ CD10+ diffuse large B-cell lymphoma].

Marfan syndrome (MFS) is caused by mutations in the gene encoding fibrillin. A 35-year-old man with MFS visited a local physician because of a sore throat. His left tonsil gradually became swollen and he was referred to our department. Histopathological examination of tonsil biopsy specimens showed diffuse proliferation of lymphoma cells with large nuclei. The tumor cells showed CD5+, CD10+, CD20+, BCL-6+, and MUM-1-. Based on these findings, the patient was diagnosed with CD5+ CD10+ diffuse large B-cell lymphoma (DLBCL). Chemotherapy combined with rituximab was administered and complete response was achieved. CD5+ DLBCL comprises approximately 5 approximately 10% of DLBCLs. In addition, CD5+ CD10+ DLBCL comprises about 5% of CD5+ DLBCLs. There may be a relationship between MFS and B-cell lymphoma because mutations in the gene encoding the receptor of transforming growth factor-beta (TGF-beta) have been implicated in the pathogenesis of MFS and downregulation of TGF-beta receptor expression has been described in the pathology of B-cell lymphoma.

Lymphoproliferative disorders after immunosuppressive therapy for aplastic anemia: a case report and literature review.

A 61-year-old Japanese man was referred to our hospital in 2002 due to severe pancytopenia. Bone marrow and peripheral blood findings indicated he had severe aplastic anemia (AA). A whole-body CT scan and Ga scintigraphy revealed no abnormal findings. Antithymocyte globulin and cyclosporine A (CyA) were administered and he got transfusion independently. In September 2004, he complained of abdominal fullness and a skin eruption in the lower abdomen. An abdominal CT revealed a spleen mass and lymphoadenopathy of the pancreas head. Splenectomy was done, and he was diagnosed with a diffuse large B cell lymphoma (DLBCL) of the spleen and skin. His karyotype was associated with t(14; 18). CyA was stopped, all lesions disappeared, and then his AA relapsed. In January 2007, antithymocyte globulin/CyA was readministered. In May 2007, he complained of acute swelling in his right thigh. A biopsy from the tumor revealed DLBCL. CyA was stopped again, yet the lymphoma did not regress. He was given R-CHOP (rituximab, cyclophosphamide, doxorubicin hydrochloride, vincristine, prednisolone), followed by 5 cycles of R-VP (rituximab, vincristine, prednisolone) and radiation therapy, resulting in a partial remission. We report DLBCL after immunosuppressive therapy for AA. Although this is a rare complication, it should be considered before beginning immunosuppressive therapy.

Clinicopathologic features and treatment outcome of primary breast diffuse large B-cell lymphoma.

We studied the clinicopathologic features and treatment outcome of patients with breast diffuse large B-cell lymphoma. As to the cellular immunophenotype, CD5 was detected in two patients, CD10 in 4, BCL2 in 20, BCL6 in 11, and MUM-1 in 17. The 5-year progression-free survival was 77% and the 5-year overall survival was 87%. Patients with the germinal center B-cell (GCB) type had a significantly better prognosis than those with the non-GCB type. The combination of anthracycline-containing chemotherapy and/or involved-field radiotherapy produced a relatively good prognosis. However, it is a heterogeneous disease with regard to histological type and pathological state.

Successful radiotherapy in a patient with primary rectal mucosa-associated lymphoid tissue lymphoma without the API2-MALT1 fusion gene: a case report and review of the literature.

Primary rectal MALT lymphoma is rare comprising less than 1% of MALT lymphomas. A 26-year-old man was referred to our hospital because of constipation and abdominal fullness. Colonoscopy revealed multiple submucosal tumors in rectum. Histopathological examination showed dense proliferation of small lymphoid cells, but lymphoepithelial lesions were not observed. The cells were CD5(-), CD10(-), CD20(+) and cyclinD1(-). The patient was diagnosed as having MALT lymphoma. The patient was negative for API2-MALT1 gene, and radiotherapy was performed and CR was achieved. With the accumulation of cases, establishment of a treatment strategy for primary rectal MALT lymphoma is expected in the future.

The GAS5 (growth arrest-specific transcript 5) gene fuses to BCL6 as a result of t(1;3)(q25;q27) in a patient with B-cell lymphoma.

The BCL6 gene is frequently disrupted at its 5' noncoding region by 3q27 chromosomal translocations in B-cell lymphoma. As a result of translocation, BCL6 is juxtaposed to reciprocal partners, such as the immunoglobulin (Ig) gene family. Besides the Ig loci, multiple non-Ig partners of the BCL6 translocation have been reported. Here we describe the identification of the GAS5 (growth arrest-specific transcript 5) gene as a novel partner of the BCL6 in a patient with diffuse large B-cell lymphoma, harboring the t(1;3)(q25;q27). In this case, the chromosome 1 breakpoint was located within the intronic small nucleolar RNA (snoRNA) sequence of GAS5 and the chromosome 3 breakpoint at 4 kb upstream of BCL6 exon 1a. As the result of chromosomal translocation, the GAS5-BCL6 chimeric transcripts were expressed, in which the 5'-terminal oligopyrimidine (5'TOP) sequence of GAS5 was fused to the whole coding sequence of BCL6. The GAS5 gene on chromosome 1q25 is the second BCL6 partner, to the SNHG5 on 6q15, which is classified as a non-protein-coding multiple snoRNA host and 5'-TOP class gene.

NM23 downregulation and lysophosphatidic acid receptor EDG2/lpa1 upregulation during myeloid differentiation of human leukemia cells.

The NM23 gene is overexpressed in many hematological malignancies and its overexpression predicts poor treatment outcomes. NM23 overexpression is thought to suppress myeloid differentiation of leukemia cells, but the molecular mechanism is unknown. In breast cancer cells, the lysophosphatidic acid (LPA) receptor EDG2/lpa1 was downregulated by NM23-H1 overexpression, and this reciprocal expression pattern was associated with suppressed or induced cell motility/metastasis. Here, we examined the relationship between EDG2 and NM23 expression during myeloid differentiation of leukemia cells. NM23 expression decreased and EDG2 expression increased during all-trans retinoic acid (ATRA)-induced myeloid differentiation of HL-60, NB4, and THP-1 leukemia cells. Moreover, this inverse correlation was more evident when myeloid differentiation was enhanced by ellagic acid, an inhibitor of NM23 activity. In contrast, there was no inverse correlation between EDG2 and NM23 expression during erythroid differentiation of HEL and K562 cells. ATRA plus LPA enhanced the motility of leukemia cells as well as breast cancer cells in an EDG2-dependent manner. These results suggest a common molecular mechanism between myeloid differentiation of leukemia cells and migration of breast cancer cells depending on NM23 and EDG2 expression levels.