Reply to Matsui et al.

Abstract

standard test for what remains a clinical dilemma, distinguishing AA from hMDS. This is in part, we believe, because CD34 numbers, although statistically different between the disease groups, showed considerable overlap in several studies. Rather than attempting to 'reinvent the wheel,' we believe that our results build upon past studies by providing clinical outcomes that improve the ability to classify patients with either disease state. When doing this, we find no overlap in marrow CD34 numbers between AA and hMDS, and thus believe quantifying marrow CD34 numbers should be further tested as a standard approach for separating the two disorders. Furthermore, these findings also suggest that patients with normal cytogenetics and low CD34 þ percentages are at a low risk of disease progression and may be managed in a conservative manner in the absence of life-threatening cytopenias.