Clinical Utility of Multiparameter Flow Cytometry in the Diagnosis of 1013 Patients With Suspected Myelodysplastic Syndrome Correlation to Cytomorphology, cytogenetics, and Clinical Data

BACKGROUND: The diagnosis and classification of myelodysplastic syndromes (MDS) is based on cytomorphology (CM) and cytogenetics (CG). Multiparameter flow cytometry (MFC) may add important diagnostic information. METHODS: To evaluate the potential role of MFC in the diagnostic setting of MDS, the authors analyzed the results from 1013 patients with suspected MDS by using CM, CG, and MFC in parallel. RESULTS: Concordance between CM and MFC was 82% for diagnostic results in 788 patients who had unequivocal CM results. An additional 225 patients had only minor dysplastic features identified by CM, including 51 patients (22.7%) who had clear evidence of MDS by MFC. Twelve patients who had no indication of MDS identified by CM had MDS-typical CG aberrations; in 6 of those patients (50%), MFC revealed MDS characteristics. In another 11 of 23 patients (47.8%) who had minor dysplastic features identified by CM and MDS-typical CG aberrations, MFC revealed MDS characteristics. The percentages of blasts determined by CM and by MFC were strongly correlated (P < .001). The frequency of aberrantly expressed antigens differed significantly between patients rated by CM as MDS (highest frequencies), suspected MDS, and no MDS (lowest frequencies). In various patients, MFC identified MDS-typical aberrant antigen expression in cell compartments that were not rated dysplastic by CM. The numbers of aberrantly expressed antigens were correlated with International Prognostic Scoring System scores and overall survival. CONCLUSIONS: The current analysis clearly demonstrated an increased diagnostic yield with MFC when added to CM and CG in patients with suspected MDS. Cancer 2010;116:4549-63. (C) 2010 American Cancer Society.