Equivalence of laser scanning cytometric and flow cytometric immunophenotyping of lymphoid lesions in cytologic samples.

The immunophenotype of lymphoid cytologic samples obtained by laser scanning cytometry (LSC) and flow cytometry (FC) was compared in 72 cases composed of a series of 23 cases with simultaneous LSC and FC immunophenotyping and a second series of 49 cases in which nonsimultaneous immunophenotyping was performed. In both series, no discordance in the population immunophenotype was found that would result in changes in diagnostic classification, although minor discordance in some antigens was found, predominantly affecting FMC7, CD11c, and CD23. The immunophenotype obtained by LSC shows a high degree of concordance with that obtained by FC and generates results that are diagnostically equivalent. Potential explanations for the discordant markers include differences related to the techniques, differences in the fluorochrome-labeled antibodies, technical factors, differences in antigen expression related to anatomic sites, temporal variations, and interpretive variances.