Abstract

This is an analysis and review of 258 cases of acute granulocytic leukemia variants diagnosed by this laboratory during the last 10 years from 1966 to 1975. The results of the study are summarized as follows. 1. The frequency ratios of the various types among the 459 cases of acute leukemia are 40.1%(184 cases) in acute myeloblastic leukemia (AML), 43.8% (201 cases) in acute Iymphocytic leukemia (ALL), 2.8% (13 cases) in acute promyelocytic leukemia (APmL), 8.3% (38 cases) in acute myelomonocytic leukemia of Naegeli type (AMML), 2.6% (12 cases) in acute monocytic leukemia of Schilling type (AMoL) and 2.4% (11 cases) in erythroleukemia including erythremic myelosis, respectively. 2. Among the 258 cases of acute granulocytic leukemia(AGL) the AML is the major type comprising 71.3% of total AGL cases and the other rare variants are AMML (14.7%), APmL(5.0%), AMoL(4.7%) and erythroleukemia including erythremic myelosis, in decreasing order of frequency. 3. Male to female sex ratios in the rare AGL variants (1.1-1.4 : 1)are similar to that of AML (1.65 ; 1) except that of the AMoL in which male is predominant (3 : 1). 4. Age incidences in the rare AGL variants are widely scattered from infancy to old age, however that of AMML is very similar to the AML showing a preponderance in childhood and young age. 5. The onset is acute in APmL so that 82% of them is diagnosed within a month. 6. For the chief complaints, the APmL cass exhibit characteristically sudden massive hemorrhagic tendencies in 92% of the cases, while gum hypertrophics are observed in 11% of the AMML cases and skin nodules with leukemic infitration in 33% of the AMoL cases, in addition to the leukemic symptoms and signs. 7. Auer’s rods are observed in 33.7% of the AML cases, 53.8% of the APmL cases, 55.3% of the AMML cases, 16.7% of the AMoL cases and 11.1% of the erythroleukemia cases. 8. There are some atypical cases or remarkable hematologic findings in AGL variants as follows ; (1) A.M.L. : One case of congenital type (about 0.5%) and one case of micromyloblastic form(about 0.5%) are found among the 184 cases. (2) A.Pm.L. : The leukemic promyelocytoid cells are observed in average of 43% and 64% in peripheral and bone marrow differential counts, respectively. (3) A.M.M.L. : The myelomonocytoid cells are observed in average of 44% and 56% in peripheral and bone marrow differential counts, respectively. The five cases of them discloses extraordinarily coarse and heavy azurophilic granulations like those of APmL in their cytoplasms, but none of them exhibited any D.I.C. finding as in APmL. (4) A,Mo.L. : The monocytoid cells are encountered in average of 56% and 77% in peripheral and bone marrow differential counts, showing more immaturity in nuclei and cytoplasms than those of AMML. (5) Erythroleukemia including erythremic myelosis : All the 11 cases revealed normoblastemia in average of l19/ 100WBC in peripheral blood. The 9 cases of erythroleukemia disclosed myeloblasts and promyelocytes in average of 11% and 5% in peripheral blood, and of 10% and 5% in bone marrow differential counts, respectively. The 3 cases of erythremic myelosis (one of the 9 erythroleukemia cases had been diagnosed as erythremic myelosis 4 months before) revealed malignant erythroid hyperplasia, erythroid series comprising in average of 81% in bone marrow differential counts, while the 9 cases of erythroleukemia 59%, and both of them showed variable degree of megaloblastoid changes with atypical mitoses in erythroid series.