Chromosomes of bone marrow from 28 patients with
acute nonlymphocytic leukemia (
ANLL) (26 with AML, 2 with AMMoL), 19 of whom had
chromosome abnormalities, were studied; 11 cases exhibited previously unreported karyotypic abnormalities. The marrows of two cases had 8-21 translocations associated with an iso-X chromosome in the female patient and with 9q13- and a missing Y in the male patient. Usually, AML patients with a 8-21 translocation have been considered to have a good prognosis; however, our cases had rather short survival times. Therefore, the prognosis of AML with an 8-21 translocation but associated with other abnormalities is still not clear. Centromere spreading (CS), which was originally reported in marrow cells of
megaloblastic anemia (B12 and
folic acid deficiency), was detected in leukemic cells, disappeared during remission, and reappeared on relapse. These findings suggest that CS may be a new type of abnormality in AML. In two patients with atypical
hypoplastic anemia and
hemolytic anemia,
chromosome abnormalities were detected at the anemic stage. One case with CS was associated with atypical
hypoplastic anemia and developed AML after 1 year; the other with 48,XY,+i(1q),+3,/12 and -14 had
hemolytic anemia and developed AMMoL 3 weeks later. Interestingly, identical clones were detected both before and after the clinical diagnosis of
leukemia. These cases strongly support the concept that some
chromosome abnormalities precede the clinical manifestations of
leukemia. The present study also revealed that lymphocytes in
ANLL respond poorly to PHA in the presence of high numbers of blasts but do respond well to
mitogens during remission. Therefore, the response of lymphocytes to PHA may serve as one criterion for determining remission.