Michito Ichimaru

An early phase II study of CPT-11: a new derivative of camptothecin, for the treatment of leukemia and lymphoma.

An early phase II study of a new camptothecin analog and an inhibitor of topoisomerase I, CPT-11, was conducted in 62 patients with refractory leukemia and lymphoma by four different treatment schedules in a multiinstitutional cooperative study. CPT-11 therapy resulted in four complete remissions (CRs) and three partial remissions (PRs) in 29 assessable non-Hodgkins lymphoma (NHL) patients, one PR in three Hodgkins disease (HD), one CR and one PR in 11 acute lymphoblastic leukemia (ALL), and one PR in 15 acute myelogenous leukemia (AML) patients. Single infusion of 200 mg/m2 every 3 to 4 weeks produced no response in both leukemia and lymphoma patients. Sixty-minute infusions of 40 mg/m2/d for 5 days every 3 to 4 weeks or for 3 days weekly produced four CRs (17%) and four PRs (17%) in 24 patients with malignant lymphoma. Sixty-minute infusions of 20 mg/m2 twice a day for 7 days every 3 to 4 weeks resulted in one CR and two PRs in 12 patients with acute leukemia. No response was seen in an acute leukemia patient by another treatment schedule. CPT-11 was effective in two (15%) of 13 primarily refractory leukemia and lymphoma cases, in two of four relapsed cases, and in seven (17%) of 41 relapsed and refractory cases. Major side effects were leukopenia (91%) and gastrointestinal (GI) (76%). CPT-11 was shown to be effective against refractory leukemia and lymphoma, and thus deserves further clinical study; the novel antitumor activity mode of this drug predicts no cross-resistance to presently available antitumor drugs.

Major prognostic factors of adult patients with advanced T-cell lymphoma/leukemia.

Eighty-one adult patients with advanced T-cell lymphoma/leukemia including 54 with adult T-cell leukemia/lymphoma (ATL), who were treated between 1981 and 1983 with vincristine, cyclophosphamide, prednisolone, and doxorubicin (VEPA) or VEPA plus methotrexate (VEPA-M) in randomized fashion, were evaluated for pretreatment characteristics. The overall complete response (CR) and the 4-year survival rates were 39.5% and 19.4%, respectively, and 69% of 32 CR patients had relapses, indicating the need for development of new effective regimens for the disease. In a multiple logistic regression analysis, only three factors, leukemic manifestation, poor performance status (PS), and a high lactate dehydrogenase (LDH) level, were significantly associated with the poor response rate. In a Cox proportional hazards model analysis, shortened survival was again significantly associated with poor PS and a high LDH level, but not with a clinical diagnosis of ATL. The two factors, PS and LDH level, that were found to be significantly associated with both CR and survival rates, were used to construct a model containing six categories of patients at increasing risk for poor response and shortened survival. These categories divided the patients into three groups with respective CR and 4-year survival rates of 75% and 53% for low-risk, 45% and 15% for moderate-risk, and 15% and 0% for high-risk. The results indicate that PS and LDH levels were the most important in predicting the response and survival of an adult patient with advanced T-cell lymphoma/leukemia. The prognosis of patients with usual peripheral T-cell lymphoma, excluding ATL, was comparable with that of advanced B-cell lymphoma. These results have important implications for the design of new prospective therapeutic trials.

Diagnostic significance of detecting pseudo‐Pelger‐Huet anomalies and micro‐megakaryocytes in myelodysplastic syndrome

To investigate the kind of morphological dysplastic changes important in the diagnosis of myelodysplastic syndrome (MDS), we examined 50 patients with MDS and 86 control subjects. Micromegakaryocytes and pseudo‐Pelger‐Huët anomalies were detected in 46 patients (92%) with MDS, and were also found in the differentiated types of acute myeloid leukaemia and chronic myeloid leukaemia, but not in other haematological disorders, or healthy subjects. We believe that evaluation of these changes would be helpful in diagnosing MDS.

Apparently Beneficial Effect of Low to Intermediate Doses of A-bomb Radiation on Human Lifespan

Among about 100,000 A-bomb survivors registered at Nagasaki University School of Medicine, 290 male subjects exposed to 50-149 cGy showed significantly lower mortality from non-cancerous diseases than age-matched unexposed males. This was deduced from the fitting of a U-shaped dose-response relationship. Reasons for this effect in males, but not in females, are discussed with reference to selection of individuals and to hormesis.

Clinical, hematologic, and pathologic features of leukemic T-cell lymphoma.

Cells obtained from malignant lymph nodes and the peripheral blood of 106 patients with non‐Hodgkins lymphomas were examined for T‐ and B‐cell characteristics. Surprisingly, 79 cases were of the T‐cell type on the basis of spontaneous rosette formation with sheep erythrocytes (E‐rosettes). Of the remaining cases, 15 were B‐cell in nature (monoclonal S‐Ig positive), seven were non T‐, non B‐cell and four cases were undetermined. Forty‐nine (62.0%) of the T‐cell malignancies were of a leukemic variety, characterized by pleomorphism in the peripheral blood cell size, and histological appearance. Most of the leukemic T‐cells showed obvious lymphocytic differentiation, with condensed nuclear chromatin and scant cytoplasm, although in many of the cases, the lymphomatous infiltrate was dominated by large or pleomorphic lymphoid cells. All tumors were of a diffuse variety, and on histologic examination included a mixed type (21 cases), PDLL forms (15 cases), a large lymphoid cell type (eight cases), and WDLL forms (five cases). Although the mixed type with a pleomorphic lymphoid infiltrate was distinctive, there has been considerable variation from case to case. Clinically this unusual T‐cell, leukemic variety of non‐Hodgkins lymphomas primarily involved middle‐aged and elderly subjects, and was characterized by wide spread organ invasion (preferentially to the liver, spleen and skin), resistence to chemotherapy, and a poor prognosis. A mediastinal mass was not observed in all cases. The patients had a median survival of only ten months.

Frequency of eosinophilia in adult T‐cell leukemia/lymphoma

Cases of adult T‐cell leukemia/lymphoma (ATLL) display several peculiar clinical features, including skin rash, hypercalcemia, and an increase in the absolute neutrophil count. The patients rarely have pronounced eosinophilia. In this study, the eosinophilia observed in lymphoproliferative disorders of 62 patients with ATLL, 27 with T‐cell lymphoma (TL), and 19 with B‐cell lymphoma (BL) was investigated. The incidence of eosinophilia (⩾ 570/μl) was higher in patients with ATLL than in patients with TL or BL. Thirteen patients with ATLL (21.0%), 3 with TL (11.1%), and 2 with BL (10.5%) had eosinophilia. Of these patients, three with ATLL and one with TL who had a pathologic diagnosis of immunoblastic lymphadenopathy (IBL) showed pronounced eosinophilia up to 10,934/μl. Because the number of eosinophils in the peripheral blood of these patients correlated both with the number of ATLL cells and the degree of lymphadenopathy and because this fluctuated with chemotherapy, it seems likely that the secretion of some lymphokines by the lymphoma cells is responsible for the eosinophilia. Cancer 1992; 69:966–971.

Leukemia in Atomic Bomb Survivors, Hiroshima and Nagasaki, 1 October 1950-30 September 1966

The incidence of leukemia in fixed cohorts of atomic bomb (A-bomb) survivors in Hiroshima and Nagasaki cities has been analyzed for the period 1 October 1950-30 September 1966. Leukemogenesis has b...

Dysmegakaryocytopoiesis in acute leukaemias: its predominance in myelomonocytic (M4) leukaemia and implication for poor response to chemotherapy

Megakaryocytopoiesis was morphologically investigated in 129 adults with de novo acute leukaemia. Three types were identified: type I (84 cases), no detectable megakaryocytes; type II (32 cases), quantitatively preserved megakaryocytes with normal morphology; type III (13 cases): quantitatively preserved megakaryocytes but with distinct dysplastic changes such as micromegakaryocytes and megakaryocytes with multiple small separated nuclei. Type III was found in M1 (one out of 21 cases), M2 (one out of 20 cases), M4 (eight out of 24 cases), M6 (two out of four cases) and hypoplastic leukaemia (one out of 13 cases). M3 cases were all classified into type I. Most of acute lymphoid leukaemia cases (21 cases) belonged to type II. Among AML cases, the complete remission (CR) rate by intensive chemotherapy with daunorubicin and cytosine arabinoside was significantly lower in type III (11%) than in types I (87%) and II (71%). Among M4 cases, CR rates in type III (14%) was also significantly lower than those in type I (75%) and II (100%). Thus, the present study indicates the importance of recognizing dysmegakaryocytopoiesis in AML for clariflcation of the heterogeneous biology or pathophysiology of acute leukaemias and formulation of an appropriate therapeutic strategy.

Cytogenetic evidence for partially committed myeloid progenitor cell origin of chronic myelomonocytic leukaemia and juvenile chronic myeloid leukaemia: both granuloctye-macrophage precursors and erythroid precursors carry identical marker chromosome

Summary. We used a micromethod for cytogenetic analysis from single haematopoietic colonies to study two adults with chronic myelomonocytic leukaemia (CMML) and a boy with juvenile chronic myeloid leukaemia (JCML) carrying distinct chromosome abnormalities, 7q—, der(21), and trisomy 21. We wanted to know if both granulocyte‐macrophage (GM) and erythroid precursors are involved in the abnormal clone. In all three patients, their chromosome abnormality was seen in almost all metaphases obtained from GM‐colonies and erythroid bursts. Peripheral blood leucocytes stimulated with phytohaemagglutinin exhibited only normal karyotypes. Clones of B‐cell produced by Epstein‐Barr virus had only normal karyotypes in the CMML patients. These findings indicate that CMML and JCML are clonal haemopathies that originate in a partially committed myeloid progenitor cell.

Adult T cell leukemia with atypical surface phenotypes: clinical correlation.

The leukemic cells of 57 patients with adult T cell leukemia (ATL) were analyzed for their immunologic surface markers. Forty-four cases showed normal mature inducer/helper T cell phenotype (typical group: E-RFC+, Leu-1+, 2a-, 3a+ MASO36c-), but the other 13 cases showed unusual surface phenotypes (variant group) and could be subdivided into several groups (V1 to V5). Four cases had absent or low Leu-1 positivity (V1: E-RFC+, Leu-1-, 2a-, 3a+, MASO36c-), while two other cases with low Leu-1 positivity had both Leu-2a and 3a, a characteristic of cortical thymocytes, but were unreactive with MASO36c (V2: E-RFC+, Leu-1-, 2a+, 3a+, MASO36c-). Three cases lacked both Leu-2a and 3a despite having other T cell markers (V3: E-RFC+, Leu-1+, 2a-, 3a-, MASO36c-). The next three cases had low rosette-forming ability with sheep RBCs (V4: E-RFC-, Leu-1- approximately +, 2a- approximately +, 3a+, MASO36c-). Interestingly, one other case showed high reactivity against anti-Leu-7, which is believed to be one of the monoclonal antibodies directed against natural killer cells (V5: E-RFC+, Leu-1+, 2a-, 3a+, 7+, MASO36c-). Clinical and hematologic differences between the typical group and variant group were investigated, and it was found that the variant group (excluding V5) have statistically significant (P less than .002) higher serum lactic dehydrogenase (LDH) activity. The overall survival in the variant group was worse than in the typical group, but it was not quite statistically significant (P = .072). The median survival time was eight months for typical cases and only four months for variant cases; six cases died within two months. The V5 case was unusual not only because the patients leukemic cells have Leu-7 antigen but also because she survived more than nine years after initial diagnosis. There seems to be some correlation between phenotypic diversity of ATL cells and prognosis.