Microscopic examination of the marrow is a mainstay of hematologic diagnosis. Even with the advent of specialized biochemical and molecular assays that capitalize on advances in our understanding of the cell biology of hematopoiesis, the primary diagnosis of hematologic malignancies and many nonneoplastic hematologic disorders relies upon examination of the cells in the marrow. An aspirate and biopsy of the marrow can be obtained with minimal risk and only minor discomfort and are quickly and easily processed for examination. The marrow should be examined when the clinical history, blood cell counts, blood film, or laboratory test results suggest the possibility of a primary or secondary hematologic disorder for which morphologic analysis or special studies of the marrow would aid in the diagnosis. Leukopenia or thrombocytopenia may require a marrow examination for diagnosis. Nonhemolytic anemia that is not readily diagnosed by blood cell examination and supporting laboratory tests often requires a marrow examination. Abnormal cells in the blood, such as nucleated red cells, white cell precursors, abnormal lymphocytes not explained by concurrent infection, and blast cells, usually require a marrow examination. In addition to determining the cellularity and morphology of precursor cells, or infiltration by nonhematopoietic cells, the study provides marrow cells for immunophenotyping, cytogenetic, molecular and genomic studies, culture of infectious organisms, and storage of marrow cells for further analysis.
HISTORY OF THE MARROW EXAMINATION
The first recorded examinations of marrow in living patients occurred in the first decades of the 20th century, first using the tibia as the source of marrow and then surgical bone biopsies. Neither technique led to routine examination of the marrow, because in the former case the tibia was usually hypocellular in adults, and in the latter case, because of the invasiveness of an open procedure and the discomfort and risk of infection and bleeding. In 1923, Arinkin devised the marrow aspiration technique,1 which was the prototype for our current aspiration procedure. Thirty years passed before the suggestion that the pelvis might be preferable to the sternum gained hold, and another 10 years passed before a practical marrow biopsy instrument was put to use. Regular use of the posterior iliac crest for aspiration and biopsy and regular use of biopsy to complement aspiration did not occur until the 1970s, when staging of lymphoma made biopsy a frequent procedure and new simpler biopsy instruments became readily available.
Acronyms and Abbreviations:
CD, cluster of differentiation; CLL, chronic lymphocytic leukemia; CML, chronic myelogenous leukemia; DMSO, dimethylsulfoxide; EDTA, ethylenediaminetetraacetic acid; FISH, fluorescence in situ hybridization; GPI, glycosylphosphatidylinositol; MDS, myelodysplastic syndrome; M:E, myeloid-to-erythroid cell ratio; MRD, minimal residual disease; PCR, polymerase chain reaction.
INDICATIONS FOR MARROW ASPIRATE OR BIOPSY
The International Council for Standardization in Hematology has published guidelines for marrow aspirate and biopsy to promote consistency in performance and reporting.2 Although marrow aspiration and biopsy techniques are safe, they should be ...