Ultrastructure of Blood Lymphocytes From Chronic Lymphocytic and Lymphosarcoma Cell Leukemia 2

Quantitative electron microscopy was used to describe 50–100 blood lymphocytes each from 39 patients with chronic lymphocytic or lymphosarcoma cell leukemia. The factors studied included the cross-sectional area of cell, nucleus, and cytoplasm, the shape of the nucleus, the number and size of mitochondria and nucleoli, and cytoplasmic and nuclear abnormalities. The shape of the nucleus was measured by the contour index (the ratio of nuclear circumference to the square root of nuclear area) and by the incidence of smooth, indented, split, and fragmented nuclei. In general, the leukemic cells of a patient differed from normal lymphocytes in one or more of these factors. The measurements suggested 4 groups of patients. In group I-A (20 patients) the lymphocytes were usually small, had sparse cytoplasm, many smooth and few indented nuclei, a low contour index, not many elongated mitochondria, and few large or multiple nucleoli. In group I-B (9 patients) the cells were similar except that the nuclei were indented and irregular in shape. In group II-B (7 patients) the cells were large with considerable cytoplasm, large nuclei, many indented nuclei, and a high contour index. The mitochondria per cell were usually increased in number and there was a high incidence of elongated mitochondria and enlarged and multiple nucleoli. In group II-A (3 patients) the cells were large but many nuclei were smooth and round. Sixteen of seventeen patients with the diagnosis of chronic lymphocytic leukemia at Hines Hospital were classified in groups I-A and I-B; 4 of 5 lymphosarcoma cell leukemias were in groups II-A and II-B.