Spectrum of Morphologic Findings in Myelodysplastic Syndrome with Ring Sideroblasts 

Keyu Liu1, Ruimin Li2, Haifang Hao3, Yifeng Wu4, Zenxian Fu5*

1Department of Clinical Laboratory, Affiliated Hospital of Engineering University of Hebei, Hebei, 056002, China

2Department of clinical Laboratory, Handan Central Hospital, Handan, 056001, China

3Department of clinical Laboratory, Handan First Hospital, Handan, 056002, China

4Department of Medical Imaging, Affiliated Hospital of Engineering University of Hebei, Hebei, 056002, China

5Department of Science and Education, Affiliated Hospital of Engineering University of Hebei, Hebei, 056002, China

*Corresponding author

Abstract: Background Myelodysplastic syndrome with ring sideroblasts (MDS-RS) is a subtype of myelo-dysplastic syndrome (MDS) according to the WHO 2016 classification. Although IWGM-MDS recommend-ed the defination of ring sideroblasts, most of the clinicians in China counting the ring sideroblasts were still depending on their own standard which was based on experience. Varying definitions of ring sideroblasts led to confusion among clinicians and misdiagnosis of MDS-RS. Methods  In this article, we proposed the new method for solving this question by reviewing 26 MDS-RS cases about their clinical, laboratorial, morphological and molecular findings retrospectively. Results The analysis of our data showed that accompanying the MDS-RS were severe erythroid dysplasia ｏｒ mild erythroid megaloblastic changes. It was a key role that ring sideroblasts played in diagnosing MDS-RS. Therefore we recommended iron stain be performed routinely for anemia patients undergoing bone marrow aspiration to exclude MDS-RS. It was important to take both quantity and size of granules into account in assessing ring sideroblasts. By analyzing ring sideroblasts in our cases we redefined two types of the ring sideroblasts. The type1 was more than 11 granules either distributed into rings ｏｒ covering two third of the perinuclear area approximately. The type 2 was 6-10 granules covered more than one third of the perinuclear area, the granules must be coarse enough to cover at least one third of the perinuclear area when having closely connected. Conclusion In summary, our results were helpful for Chinese clinicians to ｍａｓｔｅｒ the morphologic features easily，unify the standrad of the ring sideroblasts accurately and avoid the misdiagnosis of MDS-RS effectively.

Keywords: Myelodysplastic syndrome with ring sideroblasts; Ring sideroblasts; Erythroid dysplasia; Anemia; Iron stain