Case Report: Myelodysplastic syndrome- associated myeloid sarcoma: an unusual clinical presentation of a rare disease.

Emoke Horvath,Elod Nagy,Smaranda Demian

doi:10.12688/f1000research.7899.1

Emoke Horvath, Elod Nagy + Show 1 more

Open Access

https://doi.org/10.12688/f1000research.7899.1

Copy DOI

Abstract

Myeloid sarcoma results from the extramedullary homing and proliferation of immature myeloid precursors. We present the timeline, events and diagnostic pitfalls related to a 66 year-old male patient's case, admitted to the Hematology Clinic for pancytopenia, fever, weight loss and fatigue. The severe cytopenia and the few blasts observed in his blood smear indicated a bone marrow biopsy. The bone marrow showed hypercellularity and multilineage dysplasia with the presence of 15% myeloblasts. After the biopsy, he promptly developed paraplegia and nuclear magnetic resonance revealed an epidural tumour which was then resected.In the epidural tumour mass blast-like, round cells were observed with a complex immunophenotype, characterized by myeloperoxidase, CD117, CD15, CD99, leucocyte common antigen positivity and a high Ki-67 proliferation index. Considering the main differential diagnostic issues, the final diagnosis was stated as myelodysplastic syndrome-associated myeloid sarcoma. The prognosis was unfavourable, the bone marrow was quickly invaded by proliferating blast cells, and despite chemotherapy attempts, the patient died.

Highlights

Myeloid sarcoma is a rare malignant solid tumour resulting from the extramedullary proliferation of myeloblasts or immature myeloid cells, that usually precedes or accompanies acute myeloid leukaemia (AML), chronic myeloproliferative disorders, sometimes presenting as the first sign of AML1
The hypercellular bone marrow biopsy showed a multilineage dysplasia characterized by dyserythropoiesis, dysgranulopoiesis and dysmegakaryopoiesis with approximately 15% CD34/CD117 positive myeloblasts without Auer rods, associated with the presence of abnormal localisation of immature precursors (ALIP)
The monomorphic tumour cells revealed positive stainings for Leucocyte Common Antigen (LCA), myeloperoxidase (MPO), CD15 and CD117, associated with a high Ki67 index

Summary

Introduction

Introduction Myeloid sarcoma is a rare malignant solid tumour resulting from the extramedullary proliferation of myeloblasts or immature myeloid cells, that usually precedes or accompanies acute myeloid leukaemia (AML), chronic myeloproliferative disorders, sometimes presenting as the first sign of AML1. We present a case with a complex clinical manifestation resulting from the unusual localization of the tumour mass, and that coincides with the MDS involving simultaneously the bone marrow tissue. The low-level presence of blasts in the blood smear (2%) indicated a bone marrow biopsy in order to establish the diagnosis, which was effected on the second day of hospitalization.

Results

Conclusion