Progression to B acute lymphoblastic leukemia in 8p11 myeloproliferative syndrome with t(6;8)(q27;p12).

8p11 myeloproliferative syndrome is a rare hematological malignancy caused by the translocation of FGFR1. Patients present with a myeloproliferative neoplasm that frequently transforms into acute myeloid leukemia or T-lymphoblastic lymphoma/leukemia. Here, we report a molecular study of a patient with 8p11 myeloproliferative syndrome who developed acute B-lymphoblastic leukemia and then transformed to mixed-phenotype acute leukemia. A 67-year-old woman was diagnosed with a myeloproliferative neoplasm with t(6;8)(q27;p12) and was monitored for polycythemia vera. Four years later, she developed acute B-lymphoblastic leukemia with an additional chromosomal abnormality of - 7. Despite two induction regimens, she failed to achieve complete remission, and leukemia transformed into mixed-phenotype leukemia. Targeted sequencing of serial bone marrow samples identified the RUNX1 L144R mutation upon transformation to B-cell leukemia. After those two induction regimens, some RUNX1 mutation-positive leukemic cells obtained the JAK2 V617F mutation, which was associated with the emergence of myeloid markers, including myeloperoxidase.

[Acquired hemophilia A requiring plasma exchange and mechanical ventilation].

A 56-year-old man who sustained a right waist injury 1 month ago, reported to our department complaining of pain in the right waist and femur for 1 day. In a computed tomography examination, hematoma of the right iliopsoas muscle was revealed, and arterial embolization was immediately performed but was not effective. Laboratory findings showed hemoglobin levels as 5.4 g/dl, platelet of 20.2×104/µl, prothrombine time of 13.1 s, partial thromboplastin time (APTT) of 81.1 s, and a convex upward curve of the APTT cross-mixing test. The activity of the coagulation factor VIII was <1.0%, but its amount was 120%, and the level of factor VIII inhibitor was 130 Bethesda Unit/ml. Disseminated intravascular coagulation was not noted. Under the diagnosis of acquired hemophilia A, treatment with prednisolone and recombinant activated factor VII was initiated. However, APTT remained prolonged, and intubation and mechanical ventilation were required because of right hemothorax. After steroid pulse therapy and plasma exchange, APTT returned to its normal range, and the inhibitor disappeared. Thus, we finally succeeded in extubation. This case indicated that intensive care may be necessary in the early phase treatment for acquired hemophilia A.

[Systemic organ invasion accompanied by immunophenotypic change observed in extraosseous plasmacytoma].

We report a 57-year-old man who was diagnosed based on morphological findings as having extraosseous plasmacytoma of the left lower eyelid. Tumor cells were positive not only for CD38 and CD138, but also for CD19 and surface immunoglobulin lambda chain. He obtained a complete remission with irradiation and VAD therapy, but the disease relapsed one year later in the testis and popliteal fossa. Because tumor cells appeared to be blastoid, CHOP therapy was administered, and the patient achieved a temporary remission. Cytoplasmic lambda chain-positive and CD19-negative tumors eventually recurred at multiple sites including the central nervous system but not in the bone marrow. Treatment with the BD regimen and lenalidomide failed, and he died four years after the initial diagnosis.

[Detection of BCR-ABL1 chimeric gene-positive neutrophils in a patient with mixed phenotype acute leukemia].

We experienced two patients with mixed phenotype acute leukemia with t(9;22)(q34;q11.2); BCR-ABL1 according to the WHO classification 2008. The type of BCR/ABL1 was major in both patients, and the chimeric gene was also detected in neutrophils from peripheral blood by the fluorescence in situ hybridization technique. Patient 1 was a 59-year-old Japanese woman, and patient 2 a 45-year-old Japanese man. They had both developed leukemia suddenly. Their leukemic blasts expressed B cell and myeloid cell antigens, but concomitantly in patient 1 (biphenotypic) and separately in patient 2 (biclonal). Percentages of BCR-ABL1-positive neutrophils were 98% and 89%, respectively. Both patients received an imatinib (600 mg/day)-combined Hyper-CVAD regimen as induction therapy, followed by treatment with dasatinib (140 mg/day). MEC therapy was also applied between these two treatments in patient 2. At present, patient 1 has obtained complete molecular remission quantitatively and qualitatively, and patient 2 only quantitatively. Considering their acute onsets with no prior history of chronic myelocytic leukemia (CML), they were both diagnosed as having acute leukemia with Ph1, but not blastic crisis of CML. In this tyrosine kinase inhibitor era, it has become more difficult to differentiate these two types of Ph1-positive leukemia development.

[CAG-GO therapy for patients with relapsed or primary refractory CD33-positive acute myelogenous leukemia].

We previously tested a less toxic CAG regimen consisting of low-dose cytarabine, aclarubicin and granulocyte-colony stimulating factor for the treatment of patients with relapsed or refractory myeloid malignancies or elderly patients with untreated ones, obtaining a satisfactory complete remission rate of 62%. Gemtuzumab ozogamicin, an anti-CD33 monoclonal antibody conjugated to calicheamicin, has recently been approved as a single agent in Japan for the treatment of relapsed/refractory CD33-positive acute myelogenous leukemia (9 mg/m(2) on days1 and 15). Complete remission rate was reported as 30% in a phase 2 trial in Japan. In this study, effectiveness and safety of combining dose-attenuated gemtuzumab ozogamicin (3 mg/m(2) on day5) and original CAG regimen were assessed in nine patients with relapsed/refractory CD33-positive acute myelogenous leukemia and a median age of 70 years. Rate of complete remission with or without platelet recovery was 44% (4/9). The median duration of complete remission and overall survival were 5.5 and 16 months, respectively. Reversible myelosuppression and liver toxicity were the main adverse events, but no regimen-related death was recorded. Although only a small number of cases were included in this preliminary study, this CAG-GO regimen was found to be feasible and useful even in high-risk relapsed or refractory patients.

[Mediastinal large B-cell lymphoma associated with systemic sclerosis].

Malignant lymphoma (ML) is frequently associated with several forms of collagen diseases such as Sjören syndrome, systemic lupus erythematodes, and rheumatoid arthritis. However, the occurrence of ML in systemic sclerosis (SSc) patients has rarely been reported. Here we report an SSc patient who developed mediastinal (thymic) large B-cell lymphoma (MLBCL). A 31-year-old woman was diagnosed as having SSc in August 2007. The patient was treated with low-dose prednisolone (10 mg/day) without any effect. One year after the diagnosis, chest computed tomography-scan demonstrated thymic tumor in the anterior mediastinum. Thymectomy was performed, and a pathohistological diagnosis of MLBCL was established. Immunohistochemical analysis demonstrated that the tumor cells were positive for CD45 and CD20, but negative for CD30 and EBV-encoded RNA. The patient was treated with 6 courses of CHOP regimen, resulting in complete remission of lymphoma. This report describes the first SSc patient associated with MLBCL. SSc patients occasionally develop ML after a relatively short interval. Our case suggests that intensive monitoring for the development of ML is needed in newly diagnosed SSc patients.

[Asian variant of intravascular large B-cell lymphoma diagnosed by bone marrow biopsy].

A 63-year-old male presented with fever and general malaise in June 2004. On admission hepatosplenomegaly was apparent, but without lymphadenopathy. The laboratory examination revealed pancytopenia and increased levels of lactate dehydrogenase, direct bilirubin and soluble interleukin-2 receptor. Histological analysis of the bone marrow biopsy specimen demonstrated proliferation of atypical lymphoid cells positive for CD20 in the small capillaries, leading to the diagnosis of the Asian variant of intravascular large B-cell lymphoma (AIVL). The presence of rearrangement of the immunoglobulin gene confirmed the diagnosis. The patient responded well to CHOP therapy followed by seven courses of rituximab-combined CHOP therapy and has remained in complete remission up to the present. This case implies that bone marrow biopsy could be a useful examination for diagnosing AIVL and that rituximab-combinedchemotherapy could improve survival in patients with the disease.