Childhood myelodysplastic syndromes in a Brazilian population.

Fourteen pediatric cases of myelodysplastic syndrome according to French-American-British Co-operative Group (FAB) criteria were identified in a retrospective review of all cases of hematologic malignancies referred to the Pediatric Oncology division of the Cancer Hospital A. C. Camargo over a 12-year period: 1 case of refractory anemia, 8 cases of refractory anemia with excess of blasts, and 1 case of refractory anemia with excess of blasts in transformation. Three children had features consistent with chronic myelomonocytic leukemia, and one child was diagnosed with secondary myelodysplastic syndrome. The median age was 3.5 years (1 month-11 years). In 11/14 cases the disease evolved to acute leukemia. In 3 patients blasts had morphological and cytochemical features of lymphoblasts. Two of these patients had a good response to acute lymphoblastic leukemia chemotherapy protocol. The time of progression to leukemia in these cases was shorter than in those who evolved to acute myeloid leukemia. The authors believe this to be the first series of pediatric myelodysplastic syndrome documented in Brazil. Cases were characterized by aggressive FAB type, conspicuous cell atypias in all 3 hemopioetic cell lines, and a high rate of evolution to acute leukemia.