[Clinical Characteristics and Therapeutic Efficacy Evaluation of 14 Cases of Solitary Myeloid Sarcoma].

Objective: To investigate the clinical characteristics, treatment and prognosis of solitary myeloid sarcoma (MS).
Methods: The clinical data of 14 solitary MS patients were retrospectively analysed, including their clinical features and treatment, and were evaluated.
Results: A total of 14 cases of solitary MS mainly occurred in middle-aged population with the median age 41 years old (17-62 years old). The involved sites were more extensive, including breast, testis, spinal canal, skin, gastrointestinal system, nose and so on. The poorly differentiated cells of small to medium size showed diffuse distribution, relatively consistent morphology and a higher ratio of cytoplasm. The nucleus is in round or oval shape with fine and dense chromatin. Pathological mitosis was easily observed. Expression of MPO, lysozyme, CD43, myeloid-derived cells were positive. Treatment methods included surgery, chemotherapy and stem cell transplantation. Median survival time of 14 patients was 22.5 months; overall survival (OS) was 35.7% (5/14), median disease-free survival reached to 10.4 months on averge (3.5 months to 16 months), and 2-year overall survival (OS) was 50.3%.
Conclusion: The incidence of solitary MS is low, with a tendency progressing to leukemia, the chemotherapy regimen of anthracycline+cytarabine combined with radiotherapy can achieve better clinical efficacy.