Articles on Medical Diseases and Conditions

Entries for the ‘Leukemia, Lymphomas, and Myeloproliferative Syndromes’ Category

Myelodysplastic Syndromes

The myelodysplastic syndromes are a group of disorders with a varying number of features that may raise the question of early, borderline, or atypical acute leukemia but that do not satisfy FAB criteria for leukemia (especially, the FAB cutoff level of 30% blasts in the bone marrow). The disorders included in this category by the […]

Acute Leukemia

Acute leukemia comprises about half of all leukemias. Acute lymphocytic leukemia (ALL) and acute nonlymphocytic leukemia (ANLL) are about equal in overall occurrence, but differ considerably in age groups. About 80%-90% of acute leukemia in childhood is ALL, and about 85%-90% in adults is ANLL (most commonly acute myelogenous leukemia and myelomonocytic leukemia). Peak incidence […]


Malignancy may occur at each major stage in the development sequence of the blood cells. In general, the earlier the stage at which the cell is involved by malignancy, the worse the prognosis. Thus, a leukemia whose predominant cell is the myeloblast has a much worse prognosis (if untreated) than one whose predominant cell is […]

Identification of Granulocytes

Granulocyte and monocyte identification and phenotyping relies more heavily on morphology than is possible with lymphocytes. Light microscopic appearance can, if necessary, be supplemented by a limited number of cytochemical stains and enzyme tests, and in some cases by immunologic tests for CD antigens. In some cases phenotyping may require chromosome analysis using standard methods […]

Identification of T-Lymphocytes and B-Lymphocytes

Mature T-lymphocytes are usually identified by monoclonal antibody detection of CD-2 antigen and mature B-lymphocytes by demonstration of surface Ig (usually by flow cytometry methods). The earliest B-cell stages are now identified by nucleic acid probes demonstrating characteristic rearrangement of intracellular genes for each component part of the Ig receptor molecule heavy chains and kappa […]

White Blood Cell Identification and Phenotyping

WBC identification is usually done by Wright-stained peripheral blood smear examination. However, this approach creates problems due to the statistically small number of cells counted (usually 100), nonuniform cell distribution on the smear, and the need for subjective interpretation that can produce differences in cell counts in the same smear by the same technologist or […]

Leukemia, Lymphomas, and Myeloproliferative Syndromes

A consideration of the origin and maturation sequence of white blood cells (WBCs) is helpful in understanding the classification and behavior of the leukemias and their close relatives, the malignant lymphomas. Most authorities agree that the basic cell of origin is the fixed tissue reticulum cell. Fig. 7-1 shows the normal WBC development sequence. In […]