Case Report Myeloid Sarcoma: A Rare Case of an Orbital Mass Mimicking Orbital Pseudotumor Requiring Neurosurgical Intervention

License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objective. A rare case of myeloid sarcoma (MS), previously referred to as granulocytic sarcoma or chloroma, is presented. Representing a unique formof acutemyeloid leukemia (AML),MSmay rarely occur in adults. Even rarer,MSmayoccur as the initial presentation of AML.Methods. We report a singular and illustrative case of an orbital pseudotumor mimicking mass in a 65-year-old male as the initial presentation of AML. Results. Neurosurgical intervention was required to establish the definitive diagnosis via right modified orbitofrontozygomatic craniotomy as well as to decompress the optic canal, superior orbital fissure, and orbit. Conclusion. Postoperatively, he reported decreased pain and improvement of his vision. Further examination revealed decreased proptosis and improved extraocular mobility. Pathological findings demonstrated MS. We review the literature and discuss the neurosurgical relevance of MS as the initial presentation of AML. 1