Quantitative analysis of the cell surface area of neutrophils in myelodysplastic syndromes/neoplasms.

Introduction: The presence of abnormally small or large neutrophils in myelodysplastic syndromes/neoplasms (MDS) has been identified by experts and incorporated as a diagnostic feature in the World Health Organization classification. This finding remains subjective, however, and has not been quantitatively validated. We examined whether neutrophil size abnormalities in MDS can be quantified objectively.

Methods: Peripheral blood smears from 200 patients with MDS and 169 patients with diseases other than MDS were examined. Neutrophil areas were quantified using ImageJ software following the selection of nonoverlapping cells under defined smear conditions.

Results: Neutrophils with areas smaller than 170 µm2 or larger than 240 µm2 were much more frequent in the MDS group than in the non-MDS group (P < .001). Using these thresholds to define small and large neutrophils, we assessed the proportion of abnormally sized cells per case. Cases with 10% or more and 50% or more small neutrophils were much more frequent in the MDS group than in the non-MDS group (P = .002 and P < .001, respectively). Cases with 50% or more large neutrophils were much more frequent in the MDS group than in the non-MDS group (P = .03).

Discussion: This study provides objective evidence that neutrophil size abnormalities are a characteristic feature of MDS and can be quantitatively characterized.