Myeloid sarcoma: A population based retrospective study

Abstract Introduction Myeloid sarcoma (MS) is an extramedullary form of acute myeloid leukemia (AML). It is a high grade hematologic malignancy characterized by development of tumor mass of myeloid blasts. It can involve any tissue or organ and can occur without bone marrow involvement or may synchronously involve bone marrow by AML. It is a rare disease with rapid progression. The purpose of this study is to determine the racial and gender disparities and survival trends in patients with myeloid sarcoma. Methods Cases of myeloid sarcoma were collected from Surveillance, Epidemiology and End Result database Research Plus Data, 17 Registries, Nov 2024 Sub (2000-2022), using the ICD Code 9930/3. The analysis was stratified based on age, sex, race, primary site, stage, income and treatment with chemotherapy. Survival curves were compared using the Log-Rank test (GraphPad Prism). Results A total of 788 cases of myeloid sarcoma were identified, of which 59.3% were males. The malignancy was most seen in Caucasian (67.8%) followed by Hispanics (15.4%), Black (8.1%), Asians/Pacific Islanders (7.4%), and Alaskans/American Indians and unknown race <1% each. The median age of diagnosis was 64 years. Overall median of survival (MoS) was 12 months, with a 1-year OS of 49.6% (CI 95%, 45.7-53.3), 3-year OS of 35% (CI 95%, 31.1-38.5), and 5-year OS of 29% (CI 95%, 25.5-32.6). MoS were significant for Age: 0-30 years (128 months), 31-60 years (29 months), 60+ years (6 months) (p <0.0001); Race: White (10 months), Black (11 months), Hispanics (21 months), Asian/Pacific Islanders (25 months), Alaskan/Native Americans (13.5 months) (p 0.0015); Anatomical involvement: head, face & neck (59 months), thorax (21 months), abdomen & pelvis (38 months), connective tissue (11 months), hematopoietic system (11 months), nervous system (5 months), lymph nodes (6 months) and unknown primary (5 months) (p <0.0001); Stage: localized (21 months), distant (9 months), unknown stage (8 months) (p value <0.0001). Treatment based survival analysis showed: chemotherapy (17 months) vs no chemotherapy (7 months) (p <0.0001). Survival analyses based on gender and income were insignificant. Conclusion Myeloid Sarcoma is an uncommon neoplasm with very high mortality. Based on our analysis of the data, it is noted to favor male gender, and Caucasian race. Superior survival outcomes were observed with younger age, Hispanic or Asian/PI origin, head/face/neck involvement, localized stage and management with chemotherapy. No significant survival association was noted with gender and income. Further research and analysis comparing survival with the use of targeted therapy would be of paramount importance.