RESUMEN
<p><b>OBJECTIVE</b>This study was to investigate the cell morphology and cell immune phenotypic characteristics in patients with multiple myeloma (MM).</p><p><b>METHODS</b>The flow cytometry with multiparametric direct immunofluorescence technique, and CD45/SSC and CD38(+)(+)/CD138(+) gating were used to measure cell markers CD138, CD38, CD56, CD117, CD3, CD13, CD33, CD19, CD7, CD20, CD22, CD34, CD28 in 47 MM patients. At the same time the morphology examination of bone marrow cells was performed.</p><p><b>RESULTS</b>The suspicious myeloma cell ratio in MM patients was 9.42%-74.25% detected by flow cytometry, moreover, the myeloma cell ratio detected by morphology examination was 11.0%-80.6%, there was a good correlation between the two detection methods (r(2) = 0.54, P < 0.001). The ratio of antigen positive expression was as follows: 74.46% for CD138, 100% for CD38, 57.44% for CD56, 40.42% for CD117, 6.38% for CD13, 19.15% for CD33, 8.51% for CD20, 27.66% for CD28, 2.12% for CD22, 4.25% for CD34, 0% for CD3, 0% for CD19, 0% for CD7.</p><p><b>CONCLUSIONS</b>CD45/SSC and CD38(+)/CD138(+) gating technique can accurately gate multiple myeloma cell sets which need analysis, the majority of myeloma cells expreses CD138, CD38, CD56 antigens. The immunophenotypic analysis combined with the cell morphology examination more contribute to the diagnosis and differential diagnosis of multiple myeloma.</p>