Flow cytometric analysis of peroxidase negative acute leukemias by monoclonal antibodies--II. Acute megakaryoblastic and acute pro-megakaryocytic leukemias

In this report, we have described three cases of acute megakaryoblastic leukemia (AMKL) which were demonstrated by the presence of megakaryocyte-platelet-related cell-surface antigens detected by utilizing flow cytometry and monoclonal antibodies in addition to both PPO activity which was shown by ultrastructural cytochemistry and emergence of differentiation antigens while culturing these leukemic cells. The blasts of one case possessed both platelet GpIb and GpIIb/IIIa cell-surface antigens detected by 5F1 (CD36), AN51 (CDw42), and J15, P2 and HPL2 (CDw41), respectively, whereas the remaining two cases almost completely lacked Gp1b cell-surface antigen. Hence, the former was diagnosed as immature (pro) megakaryocytic leukemia and the latter as AMKL from the viewpoint of immunophenotypic analysis as discussed in this article.

Aggressive natural killer cell leukemia/lymphoma with N901-positive surface phenotype: evidence for the existence of a third lineage in lymphoid cells

The morphology, immunologic and functional properties of peripheral blood and bone marrow cells or cultured cells from 2 patients with clinically aggressive non-T, non-B lymphoma/leukemia are described. The leukemic cells possessed medium to large granules in the cytoplasm, antigens against CD38, CD2, CD25, OKIa1, CD16, TA-1, CD9, CD24 and NKH-1 (N901) monoclonal antibodies on their cell surface, and also showed a high natural killer (NK) activity. Phenotypically, the cells in these disorders were quite different from T gamma leukemia cells bearing Fc receptor or the traditionally reported NK leukemia cells possessing HNK-1 (Leu 7) antigens on their surface. In addition, these leukemias/lymphomas belonged to neither T- nor B-cell lineage, proved by studying clonal gene rearrangement for the T beta and T gamma receptor, and immunoglobulin. Hence, a quite interesting and important point, as suggested by our data, is that all our cases expressed an antigen for NKH-1 (N901), which is detectable on all NK cell surfaces and they lacked the antigen for Leu 7 (HNK-1), which is usually detected on the surface of leukemic NK cells. These facts indicate that we are dealing with a leukemic NK cell subset which is quite different from cells of all other reported cases of NK cell leukemias. We therefore concluded that such disorders with an aggressive clinical nature and a poor prognosis as in our cases belong to a new clinical entity originating from a portion of the NK cell subset.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effect of cefotaxime on hemostasis]

We conducted hemostatic studies with 1,043 adult patients with various diseases who were treated for their infection with cefotaxime (CTX) in 368 hospitals throughout Japan. Underlying diseases in 1,012 patients were nonhematological disorders and those in 31 were hematological diseases. Thirteen (1.2%) out of 1,043 patients showed some abnormal results in blood coagulation tests following the administration of CTX. All the 13 cases with abnormal blood coagulation tests had poor dietary intake, and appeared to have liver damage before or during the drug administration, but in none of the cases which had abnormal laboratory findings were clinical bleeding symptoms observed. Consequently, we have concluded that the incidence of abnormal hemostatic tests following CTX administration is low, and that the appearance of abnormal tests is most likely dependent upon the condition of the patient.

A case of leukemic mastocytoma terminating in metamorphosis

A case of leukemic mastocytoma terminating in metamorphosis is reported. Three types of mastocytoma cells appeared in the peripheral blood and bone marrow, each differing in cytochemical staining and maturation ability in both in vitro and in vivo cultures. Most immature mastocytoma cells, which contained no granules and were lymphoblast-like cells, differentiated to have basophilic and metachromatically positive granules in the cytoplasm after culture in the diffusion chamber, resembling more mature cells (type II). Mature cells (type II), which had diffusely dispersed and metachromatically positive granules in the cytoplasm, came to have vacuoles with basophilic substances after culture in vitro, resembling most mature cells (type I) which contained large and clumped granules with metachromasia. These findings together with clinical findings and results of morphological studies suggest that most immature cells originate from second mature or most mature cells and effect a blastic transformation.

Double minute chromosomes in acute myeloblastic leukemia

Two patients with acute myeloblastic leukemia (AML) with double minute chromosomes (dmins) are described. One patient had dmins in approximately one-third of bone marrow cells examined at diagnosis; no other karyotypic changes were observed. The dmins disappeared when the patient achieved a complete remission. The second patient developed acute leukemia as a second cancer, having previously received radiotherapy and chemotherapy for a breast carcinoma. At the time of diagnosis of AML, the patient exhibited dmins in 12% of bone marrow cells; other complex karyotypic changes were observed. Data on the clinical and cytogenetic features of these cases are compared with those of other reported cases of acute leukemia with dmins. The possible biologic and clinical significance of dmins in acute leukemia is discussed.