Cell Count Differentials by Cytomorphology and Next-Generation Flow Cytometry in Bone Marrow Aspirate: An Evidence-Based Approach Ríos Tamayo, Rafael Sánchez Pérez, María José Bone marrow aspirate Cytomorphology Next generation flow Differential cell counts 200 vs 500 cutoffs; ISO15189 Preanalytical quality Multiple myeloma Plasma cells Blasts Diagnostic efficiency Clinical laboratory Clinical significance Despite a lack of evidence, a bone marrow aspirate differential of 500 cells is commonly used in the clinical setting. We aimed to test the performance of 200-cell counts for daily hematological workup. In total, 660 consecutive samples were analyzed recording differentials at 200 and 500 cells. Additionally, immunophenotype results and preanalytical issues were also evaluated. Clinical and statistical differences between both cutoffs and both methods were checked. An independent control group of 122 patients was included. All comparisons between both cutoffs and both methods for all relevant types of cells did not show statistically significant differences. No significant diagnostic discrepancies were demonstrated in the contingency table analysis. This is a real-life study, and some limitations may be pointed out, such as a different sample sizes according to the type of cell in the immunophenotype analysis, the lack of standardization of some preanalytical events, and the relatively small sample size of the control group. The comparisons of differentials by morphology on 200 and 500 cells, as well as by morphology (both cutoffs) and by immunophenotype, are equivalent from the clinical and statistical point of view. The preanalytical issues play a critical role in the assessment of bone marrow aspirate samples. 2023-05-16T08:43:45Z 2023-05-16T08:43:45Z 2023-03-11 info:eu-repo/semantics/article Ríos-Tamayo, R.; Sánchez, M.J.; Gómez-Rojas, S.; Rodríguez-Barranco, M.; Segura, G.P.; Redondo-Sánchez, D.; CARREÑO-TARRAGONA, G.; Nicolás, A.R.; Ruiz-Cabello, F.; Jiménez, P.; et al. Cell Count Differentials by Cytomorphology and Next-Generation Flow Cytometry in Bone Marrow Aspirate: An Evidence-Based Approach. Diagnostics 2023, 13, 1071. [https:// doi.org/10.3390/ diagnostics13061071] https://hdl.handle.net/10481/81570 10.3390/ diagnostics13061071 eng http://creativecommons.org/licenses/by/4.0/ info:eu-repo/semantics/openAccess Atribución 4.0 Internacional MDPI