Myeloid Sarcoma: A Retrospective Analysis in a General Community Hospital

Introduction:
Myeloid sarcoma and leukemia cutis are extramedullary (EM) manifestations of acute myeloid leukemia (AML). Leukemia cutis (LC) refers to the infiltration of any of the skin layers by leukemia cells and myeloid sarcoma (granulocytic sarcoma or chloroma) refers to EM tumor(s) composed of immature myeloid cells. These manifestations can occur before, during or after evidence of bone marrow involvement by AML. They can develop in a single anatomical site or be disseminated with multiple sites involvement and with or without bone marrow involvement. Rarely, myeloid sarcoma may present at the time of relapse. The diagnosis is made with a combination of clinical features and a tissue biopsy. This retrospective cohort analysis describes the clinical characteristics, cytogenetics, and treatment outcome of patients with myeloid sarcoma at a general community hospital.
Methods:
This is a retrospective cohort study of patients from January 1 , 2017 to July 1 , 2022 with biopsy proven myeloid sarcoma admitted to Memorial Hermann Hospital at The Texas Medical Center in Houston, Texas. Baseline clinical characteristics, demographics, laboratory data, treatment regimen and clinical outcomes were retrieved and analyzed. Data was expressed as counts, percentages and median.
Results:
Among 125 patients (94 AML and 31 APL), there were six patients with biopsy proven myeloid sarcoma. The median age was 51 (range 27-68) years. Five patients were females, 3 (50%) were Caucasian, one African American, one Hispanic and one has other race. Primary or de novo myeloid sarcoma were identified in 4 (67%) of patients and, myeloid sarcoma at relapse with antecedent hematologic malignancy were identified in 2 (33%). Two patients had primary mediastinum myeloid sarcoma, 2 had intracranial myeloid sarcoma at relapse, one with primary spine myeloid sarcoma and one with primary bilateral breast myeloid sarcoma. Interestingly, one patient with intracranial myeloid sarcoma had history of acute promyelocytic leukemia (APL) and had EM relapse 8‚Äâyears later. The second patient with intracranial myeloid sarcoma had history of AML that underwent hematopoietic stem cell transplant and had EM relapsed 5‚Äâyears later.
Discussion:
Although there are no prospective study looking at prognosis of myeloid sarcoma due to its rarity, the clinical outcomes of patients with myeloid sarcoma treated with intensive induction chemotherapy regimens used in AML seems to be a reasonable and feasible therapeutic option.