The identification and quantitation of cellular antigens with fluorochrome-labeled monoclonal antibodies (“immunophenotyping”) is one of the most important applications of the flow cytometer. Immunophenotypic analysis is critical to the initial diagnosis and classification of the acute leukemias, chronic lymphoproliferative diseases, and malignant lymphomas since treatment strategy often depends upon antigenic parameters. In addition, immunophenotypic analysis provides prognostic information not available by other techniques, provides a sensitive means to monitor the progress of patients after chemotherapy or bone marrow transplantation, and often permits the detection of minimal residual disease. Flow cytometric analysis of apoptosis, multidrug resistance, leukemia-specific chimeric proteins, cytokine receptors and other parameters may provide additional diagnostic or prognostic information in the near future.
Flow cytometry has become an essential tool in the diagnosis of hematologic and lymphoid neoplasia by aiding in determining whether a clonal proliferation is B- or T-cell in origin; and in most cases help with a specific diagnosis, when a classic pattern is present. . The unique capability of flow cytometry to rapidly analyze, even in small samples, multiple cell properties simultaneously such as size, granularity, surface and intracellular antigens and DNA content allow for increased sensitivity in the detection of neoplastic cells and should contribute to improving accuracy and precision in the diagnosis and classification of lymphomas and lymphoprolferative disorders.
It must be emphasized, however, that flow cytometry is an adjunct to the clinical history and the microscopic examination of cells.(!5.)
