Consensus protocol for the flow cytometric immunophenotyping of hematopoietic malignancies. Working Group on Flow Cytometry and Image Analysis.

Flow cytometry has become the preferred method for the lineage assignment and maturational analysis of malignant cells in acute leukemias and lymphomas. Multiparametric immunophenotyping allows the detection of aberrant antigen coexpression and the analysis of heterogeneity and clonality of malignant cells in leukemias and lymphomas. The complexity of multiparameter analysis techniques and the multitude of available monoclonal antibodies demand a standardization of protocols for the use of flow cytometry in clinical laboratories in order to achieve interlaboratory reproducibility. Therefore, the Working Group on Flow Cytometry and Image Analysis has started an initiative in order to establish a consensus protocol on the current methods of the phenotyping of hematological neoplasias as a basis for quality assurance and support for upcoming technologies such as quantitative analysis of antigen densities and automated knowledge-based analysis software. In addition to general recommendations on assay procedures and quality control specific recommendations are given for the selection of two-color reagent panels and data interpretation in an attempt to define a basis for cross-evaluation against the different currently established laboratory protocols.