Flow cytometry: Immunophenotyping in 48 hairy cell leukemia cases and the relevance of fluorescence intensity in CDs expression for diagnosis

• Published in: Einstein (São Paulo, Brazil) Vol. 5; no. 2; pp. 123 - 128
• Main Authors: Nydia Strachman Bacal, Eduardo Mantovani, Silvia Grossl, Sonia Tsukasa Nozawa, Ruth Hissae Kanayama, Ana Claudia Miranda Brito, Claudio Ernesto Mendes Albers, João Carlos de Campos Guerra, Cristóvão Luis Pitangueira Mangueira
• Format: Journal Article
• Language: English
• Published: Instituto Israelita de Ensino e Pesquisa Albert Einstein 01-06-2007
• Subjects: Antibodies; Flow cytometry; hairy cell; Immunophenotyping; Leukemia; monoclonal
• ISSN: 1679-4508

Objectives: To report the experience and the importance of flowcytometry immunophenotyping by measuring the positivity andantigenic expression intensity in the diagnosis of 48 patients withhairy cell leukemia (HCL). Methods: From November 1991 to June2005, 4318 cases were analyzed by flow cytometry, 3556 (82.3%) ofwhich were oncohematological diseases. Forty-eight cases of hairycell leukemia (1.3%) were diagnosed. Morphological analysis wasperformed on slides stained with Grunwald Giemsa panchromaticdye, analyzed by two experienced professionals. The cytochemicalanalyses made were for acid phosphatase and tartrate-resistant acidphosphatase (TRAP). For antigenic expression analysis, the monoclonalantibodies used were: CD2, CD3, CD5, CD7, CD10, CD11c, CD19,CD20, CD22, CD23, CD25, CD38, HLA-DR, FMC-7, CD79b, CD103,IgM, IgG, IGD, kappa and lambda. Results: By analyzing positivity andmonoclonal antibody expression intensity in the forward scatter vs.side scatter histograms (used between 1991 and 2001), and in CD19vs. SSC histograms with sequential histograms (after 2001), it waspossible to confirm this pathology and to discriminate residual cellsafter the specific therapy. Conclusion: Diagnostic confirmation of hairycell leukemia by flow cytometry is a fast and accurate method that isuseful in the clinical laboratory. The option for an initial CD19 vs. SSChistogram and an analysis of antigenic expression intensity in the bonemarrow showed to be statistically more efficient.