Abstract
BACKGROUND: Myelodysplastic syndromes (MDSs) are a group of hematological diseases caused by expansion of an abnormal clone of hematopoietic stem cells. Primary MDS is a potentially premalignant clonal disorder that may progress to overt acute leukemia in 25%-50% of cases. However, most of these cases evolve into acute myeloid leukemia and rarely progress to acute lymphoblastic leukemia (ALL). Thus, transformation of MDS into B-cell ALL is rare. CASE SUMMARY: A 58-year-old man was admitted to the hospital for reduced blood cell counts. Based on all the test results and the World Health Organization diagnosis and classification, the patient was finally diagnosed with ring-shaped sideroblastic MDS with refractory hemocytopenia due to multilineage dysplasia. We used red blood cell transfusions and other symptomatic support treatments. After 4 years, the patient felt dizziness, fatigue, and night sweats. We improved bone marrow and peripheral blood and other related auxiliary examinations. He was eventually diagnosed with B-lineage acute lymphocytic leukemia (MDS transformation). CONCLUSION: The number of peripheral blood cells, type of MDS, proportion of primitive cells in bone marrow, and number and quality of karyotypes are all closely related to the conversion of MDS to ALL.