Philadelphia chromosome-positive acute lymphoblastic leukemia and Down syndrome.

Children with Down syndrome (DS) are at high risk of developing acute lymphoblastic leukemia (ALL), but Philadelphia chromosome-positive (Ph+) ALL is rare in DS children. We report a case of Ph+ALL with DS complicated by chronic heart failure. Complete molecular remission was obtained after imatinib-combined chemotherapy, although infectious episodes during the neutropenic period worsened the heart condition.

Hematopoietic stem cell transplantation for pediatric mature B-cell acute lymphoblastic leukemia with non-L3 morphology and MLL-AF9 gene fusion: three case reports and review of the literature.

Mature B-cell acute lymphoblastic leukemia (B-ALL) is typically associated with French-American-British (FAB)-L3 morphology and MYC gene rearrangement. However, rare cases of mature B-ALL with non-L3 morphology and MLL-AF9 fusion have been reported, and such cases are characterized by a rapid and aggressive clinical course. We here report three such cases of pediatric mature B-ALL in female patients respectively aged 15 months, 4 years, and 4 months.