Atypical orbital mass as the precursor for myelodysplastic syndrome recurrence: a case report.

Purpose: Myelodysplastic syndrome (MDS) has the potential to progress into acute myeloid leukemia (AML), even in patients in remission. Granulocytic sarcomas are extramedullary manifestations of AML that can rarely occur in the orbit and in the absence of systemic signs of disease. We describe the unusual presentation of an isolated orbital mass in an adult patient at high-risk for development of AML. Observations: A 42-year-old male with a history of MDS in remission for nearly two years after chemotherapy and bone marrow transplant presented with unilateral eye pain and swelling, blurry vision, diplopia, and dizziness. Imaging revealed a unilateral intraconal extraocular mass, and laboratory workup at that time was negative for signs of systemic disease. Multiple biopsies showed no pathologic or immunohistochemical signs of malignancy. A bone marrow biopsy ultimately revealed MDS recurrence with AML. Conclusions and Importance: This case highlights the unusual manifestation of AML as a unilateral extraocular mass and the importance of clinical correlation with negative pathological studies. It is crucial to accurately establish a diagnosis of AML to improve patient outcomes, especially in high-risk cases.