Myeloid Sarcoma as a Presentation of Acute Myeloid Leukemia and Blastic Phase in the Course of Chronic Myeloid Leukemia: A Case Report and Literature Review

Background: Myeloid sarcoma (MS), also known as granulocytic sarcoma or chloroma, is a rare disease entity characterized by the emergence of an extramedullary tumor, which may be antecedent, coexisting, or manifest secondarily to an ongoing malignancy of lymphoid origin. Owing to its low prevalence, scientific reports addressing this matter comprise mainly retrospective studies with a limited number of participants, rather low-quality research, and only few case reports. Despite MS's rarity, the need for enhancing their diagnostic tools and refinement of their therapeutic regimens is broadly recognized among physicians. Case summary: In this case series, we present the clinical histories of two patients diagnosed with MS. The former (Case 1) exhibited MS of the sternum alongside chronic myeloid leukemia (CML), while in case of the latter (Case 2) MS presented as the initial manifestation of a current acute myeloid leukemia (AML). Treatment for both patients included chemotherapy (CHTH) and radiation (RT); however, patient 1 with CML died due to cardiorespiratory insufficiency secondary to an infection, while patient 2 is in clinical remission (CR) for 16 months since their MS diagnosis. Furthermore, a comprehensive analysis of previously reported cases was conducted which incorporated MS in patients with AML and CML. Conclusion: The objective of this report was to emphasize the heterogeneity among the clinical manifestations of MS, to underline the relevance of the histopathological and molecular diagnostic tools in opting for the appropriate therapy, and that, in spite of it occurring rather uncommonly, physicians should think of MS in the presence of pathological masses in patients under risk of hematological malignancies.