Isolated Granulocytic Sarcoma: Case Reports of Three Rare Presentations and Review

Granulocytic sarcomas are rare, extramedullary tumors composed of immature myeloid cells. Traditionally, these tumors present in patients with known leukemias; however, granulocytic sarcomas may present as an isolated finding in patients without known disease. As such, isolated granulocytic sarcomas may present a diagnostic challenge for clinicians taking care of the patient. Moreover, these tumors also create a therapeutic challenge for clinicians as they generally carry a poor prognosis and often have short-lived responses to systemic therapy with cytarabine-based chemotherapy. An improved understanding of the biology of granulocytic sarcomas may reveal targets accessible to some of the new biologically active agents being studied across oncology. This report of 3 usual presentations of granulocytic sarcomas and a brief review of the known pathophysiology reminds us that there is much work to do to improve outcomes for our patients.