Hiroshi Gomyo

Prospective measurement of Epstein-Barr virus-DNA in plasma and peripheral blood mononuclear cells of extranodal NK/T-cell lymphoma, nasal type

Epstein-Barr virus (EBV)-DNA was prospectively analyzed in plasma and mononuclear cells (MNCs) from peripheral blood in patients with extranodal natural killer (NK)/T-cell lymphoma, nasal type, to evaluate the clinical significance for diagnosis, monitoring the tumor burden, and prognostication. Thirty-three patients were enrolled, and 32 were evaluable. Pretreatment plasma and MNC EBV-DNA was detectable in 14 (range, 50-71 000 copies/mL) and 6 patients (range, 20-780 copies/μg DNA), respectively, and both were well correlated (r = 0.8741, P < .0001). Detectable plasma EBV-DNA was associated with higher clinical stage (P = .02), presence of B symptoms (P = .02), worse performance status (P = .02), and higher serum soluble IL-2 receptor level (P < .0001). Twenty-two patients attained complete response. Plasma EBV-DNA level was significantly higher in nonresponders than in responders (mean, 16,472 vs 2,645 copies/mL; P = .02). Multivariate analysis showed clinical stage (hazard ratio, 9.0; 95% confidence interval, 1.8%-45.0%) and pretreatment plasma EBV-DNA (hazard ratio, 10.6; 95% confidence interval, 1.3%-87.0%) were significant prognostic factors. Three-year overall survival of plasma EBV-DNA positive and negative patients was 42.9% and 94.4%, respectively (P = .0009). Plasma was a preferable sample for this purpose in NK/T-cell lymphoma, nasal type, and EBV-DNA level was a good indicator for response and overall survival.

Quantitation of minimal residual disease in t(8;21)-positive acute myelogenous leukemia patients using real-time quantitative RT-PCR.

t(8;21) is one of the common chromosomal translocations in acute myelogenous leukemia (AML). Using a recently developed real‐time quantitative polymerase chain reaction (PCR) system, we analyzed the minimal residual disease (MRD) in bone marrow samples from seven AML patients with t(8;21) at different time points during the clinical courses of their disease. Four of these patients received chemotherapy and allogenic bone marrow transplantation (allo‐BMT), and the other three were treated with chemotherapy alone. Two of the patients that received allo‐BMT suffered a relapse. In these patients, the levels of AML1‐MTG8 mRNA expression were shown to quantitatively increase. After re‐induction chemotherapy and donor lymphocyte infusion therapy, AML went into remission and the expression levels decreased. In the other two patients receiving allo‐BMT, the disease went into remission and the level of AML1‐MTG8 mRNA expression remained under the detectable range. The other three patients received several courses of chemotherapy, without allo‐BMT, and all of them clinically reached the hematological and cytogenetic remission state. However, there were low but detectable levels of MRD in their bone marrow samples. These results suggest that the real‐time quantitative PCR assay is very useful for the monitoring of MRD and detecting an early relapse. This assay may also be useful in determining the quantitative difference in myelo‐ablative activity between the chemotherapy alone and chemotherapy in conjunction with allo‐BMT. Am. J. Hematol. 64:101–106, 2000.

Developmental expression of EphB6 in the thymus: lessons from EphB6 knockout mice ☆

A member of the largest family of receptor protein kinases, EphB6, lacks its intrinsic kinase activity, but it is expressed in normal human tissues. To investigate the physiological function of EphB6, we generated EphB6 deficient mice. EphB6(-/-) mice developed normally, revealed no abnormality in general appearance, and were fertile. Although a developmental increase of EphB6 in the fetal thymus was confirmed, T-cell development in various lymphoid organs of EphB6(-/-) mice was comparable to those of EphB6(+/+). Even in fetal thymus organ cultures, any developmental differences of EphB6(-/-) and EphB6(+/+) thymocytes were undetectable. The different binding characteristics to ephrin-Fc proteins between EphB6(-/-) and EphB6(+/+) thymocytes demonstrated that ephrin-B2 is the unique ligand for EphB6 among eight known ephrins. While EphB6 was a dominant receptor that binds to ephrin-B2 in adult thymocytes, fetal ones also expressed another EphB that binds to ephrin-B2. Overlapping expression of the EphB subfamily in the fetal thymus might compensate for the loss of EphB6 during the thymic development.

Tamibarotene As Maintenance Therapy for Acute Promyelocytic Leukemia: Results From a Randomized Controlled Trial

PURPOSE The introduction of all-trans-retinoic acid (ATRA) has significantly improved outcomes for acute promyelocytic leukemia (APL), although a subset of patients still suffer relapse. The purpose of this study was to evaluate the role of maintenance therapy with the synthetic retinoid tamibarotene in APL. PATIENTS AND METHODS Patients with newly diagnosed APL in molecular remission at the end of consolidation therapy were randomly assigned to receive ATRA or tamibarotene, both orally, for 14 days every 3 months for up to 2 years. RESULTS A total of 347 patients were enrolled. Of the 344 eligible patients, 319 (93%) achieved complete remission. After completing three courses of consolidation therapy, 269 patients underwent maintenance random assignment. The relapse-free survival (RFS) rate at 4 years was 84% for the ATRA arm and 91% for the tamibarotene arm (hazard ratio [HR], 0.54; 95% CI, 0.26 to 1.13). When the analysis was restricted to 52 high-risk patients with an initial WBC count ≥ 10.0 × 10(9)/L, the intergroup difference was statistically significant, with 4-year RFS rates of 58% for the ATRA arm and 87% for the tamibarotene arm (HR, 0.26; 95% CI, 0.07 to 0.95). For patients with non-high-risk disease, the HR was 0.82 (95% CI, 0.32 to 2.01). The test for interaction between treatment effects and these subgroups resulted in P = .075. Both treatments were generally well tolerated. CONCLUSION In this trial, no difference was detected between ATRA and tamibarotene for maintenance therapy. In an exploratory analysis, there was a suggestion of improved efficacy of tamibarotene in high-risk patients, but this requires further study.

A novel t(2;6)(p12;q23) appearing during transformation of follicular lymphoma with t(18;22)(q21;q11) to diffuse large cell lymphoma.

Follicular lymphoma is characterized genetically by t(14;18)(q32;q21), whereas t(18;22)(q21;q11), a rare variant form of t(14;18), has been preferentially observed in chronic lymphocytic leukemia (CLL). We describe here an unusual case of follicular lymphoma with a t(18;22)(q21;q11), that progressed to diffuse large cell lymphoma with a novel t(2;6)(p12;q23). Spectral karyotyping revealed that add(2)(p12) and add(6)(q23) were derived from a t(2;6)(p12;q23). Fluorescence in situ hybridization analysis confirmed rearrangements of the BCL2 gene at 18q21 and the BCL6 gene at 3q27. Our results indicate that a reciprocal translocation involving 6q23 could be implicated in the progression of follicular lymphoma and that t(18;22) may have a specific role in the pathogenesis of follicular lymphoma as well as CLL.

CD56-positive diffuse large B-cell lymphoma: possible association with extranodal involvement and bcl-6 expression

Abstract Among B-cell non-Hodgkins lymphomas, neural cell adhesion molecule/CD56 expression is exceptional. In this study, seven cases of CD56-positive diffuse large B-cell lymphoma (DLBCL) are described. The frequency of CD56-positive DLBCL was 7% in our hospital. Four of seven (57·1%) cases expressed both CD10 and bcl-6 suggestive of a germinal center B-cell phenotype. Six of seven (85·7%) cases expressed bcl-6. Two cases expressed aberrant T cell-associated antigens, one each of CD7 and CD8. However, none of these seven cases showed CD5 expression. No significant difference was observed between CD56-positive and CD56-negative DLBCL in terms of the five international prognostic index risk factors. However, all seven cases had at least one extranodal involvement and showed a good response to initial treatment. The predominance of extranodal involvement in our series may be associated with the adhesion-related function of CD56. A high frequency of bcl-6 expression may be associated with a more favorable clinical course and prognosis.

t(14;18)(q32;q21)-bearing pleural MALT lymphoma with IgM paraproteinemia: Value of detection of specific cytogenetic abnormalities in the differential diagnosis of MALT lymphoma and lymphoplasmacytic lymphoma

Abstract A 67-year-old woman presented with a pleural effusion and a tumor in the right pleural wall. Histological examination of thoracoscopic tumor and pleural biopsy specimens showed infiltration by medium sized cells, some of which showed plasmacytoid differentiation. In view of the presence of IgM paraproteinemia and bone marrow involvement by lymphoma cells, the patient was diagnosed tentatively as having lymphoplasmacytic lymphoma (LPL). However, chromosomal analysis of the cells in the pleural fluid detected t(14;18)(q32;q21), while fluorescence in situ hybridization was positive for 11% of the MALT1 split signal. Because of the presence of characteristic genetic abnormalities and notable extranodal involvement, the patient was diagnosed as having MALT lymphoma. She was treated with three courses of cladribine and rituximab, and achieved complete regression of the tumor. In this case the detection of t(14;18)(q32;q21) involving IGH and MALT1 was useful for the differential diagnosis of LPL and MALT lymphoma.

Paroxysmal nocturnal hemoglobinuria induced by the occurrence of BCR-ABL in a PIGA mutant hematopoietic progenitor cell.

Paroxysmal nocturnal hemoglobinuria induced by the occurrence of BCR-ABL in a PIGA mutant hematopoietic progenitor cell

Dose-adjusted EPOCH chemotherapy for untreated peripheral T-cell lymphomas: A multicenter phase II trial of West-JHOG PTCL0707

The standard CHOP therapy for peripheral T-cell lymphoma has resulted in unsatisfactory outcomes and it is still not clear what is the optimal front-line therapy. We conducted a multicenter phase II study of dose-adjusted etoposide, doxorubicin, and cyclophosphamide with vincristine and prednisone (EPOCH) for untreated peripheral T-cell lymphoma patients. In this prospective study, 41 patients were treated with dose-adjusted-EPOCH as initial therapy: peripheral T-cell lymphoma-not otherwise specified, n=21; angioimmunoblastic T-cell lymphoma, n=17; anaplastic lymphoma kinase-positive anaplastic large cell lymphoma, n=2; and anaplastic lymphoma kinase-negative anaplastic large cell lymphoma, n=1. Median patient age was 64 years (range: 32–79 years). According to the International Prognostic Index criteria, 51.2% were at high-intermediate or high risk. The overall response and complete response rates were 78.0% [95% confidence interval (CI): 62.4–89.4%] and 61.0% (95%CI: 44.5–75.8%), respectively. At the median follow up of 24.0 months, the 2-year progression-free survival and overall survival were 53.3% (95%CI: 36.4–67.5%) and 73.2% (95%CI: 56.8–84.1%), respectively. The younger patients (≤ 60 years old) had a high response rate (overall response 94.1% and complete response 70.6%) and survival rate (progression-free survival 62.5% and overall survival 82.4%). The most common grade ≥ 3 adverse events were neutropenia (74.5%), anemia (40.8%), thrombocytopenia (22.0%), and febrile neutropenia (9.0%). Dose-adjusted-EPOCH had a high response rate with a tolerable toxicity profile. Our results indicate that dose-adjusted-EPOCH is a reasonable first-line approach for peripheral T-cell lymphoma patients and may improve outcomes.

Philadelphia chromosome positive acute lymphoblastic leukemia showing normal karyotype in G-banding chromosomal examination before chemotherapy

Abstract A 29-year-old male was admitted because of thrombocytopenia. A diagnosis of acute lymphoblastic leukaemia was made on the basis of a 61.6% infiltration of leukemic cells in his bone marrow. Standard G-binding chromosome analysis of bone marrow cells revealed a normal karyotype. He received combination chemotherapy, and achieved hematological complete remission. However, chromosomal analysis of bone marrow cells after 2 courses of consolidation therapy showed the Philadelphia (Ph) chromosome in two cells out of 20 analysed. We retrospectively examined the sample of bone marrow cells before chemotherapy; It showed minor BCR/ABL positivity with FISH and RT-PCR methods. The Ph chromosome disappeared after consolidation chemotherapy and allogeneic bone marrow transplantation, but the Ph chromosome reappeared at relapse. We postulated that there were two clones, both a Ph-positive clone and Ph-negative clone. At the initial diagnosis, Ph chromosome was not detected because the G-banding method analyzed only metaphase cells, which contained few Ph-positive clones. In order to offer effective therapy with molecular targeting agents, in this poor prognostic disease, it is necessary to detect Ph chromosome before the first chemotherapy and BCR/ABL detection with FISH or RT-PCR methods appears more useful than G-banding chromosome analysis.