[Acute myeloid leukemia in children with Down syndrome]

Forty-four children, aged between 0.4 and 16.2 years (median 2.0 years) with Down's syndrome and acute myelogenous leukemia (AML) including subacute megakaryoblastic leukemia (M7) were diagnosed between 1980 and 1986 (group 1, n = 16) or between 1987 and 1992 (group 2, n = 28). The leukemic blasts from Down's syndrome patients often proved difficult to classify. In group 1 the most frequent diagnoses were FAB M5 (6 pts.), M6 (3 pts.), in 3 patients the morphological diagnosis of M7 can retrospectively be assumed. In group 2, 15 of 28 patients were classified as M7, in 3 patients based on morphology alone, and in the other 12 patients confirmed by immunophenotyping or biopsy. The other children in group 2 were classified as: FAB M0 (3 pts.), M1 (1 pt.), M4 (2 pts.), M5 (2 pts.), M6 (4 pts.), M6/M7 (1 pt.). Initially, the latter and 10 of the patients with M7 presented with < 30% of blasts in the bone marrow. Karyotyping in 12 of 13 children frequently revealed numeric abnormalities, particularly trisomies involving chromosomes 8 (n = 6), 11 (n = 3), 21 (n = 3) and 14 (n = 1) in addition to the constitutional + 21c. Six patients in group 1 received no specific treatment, while 10 children were treated according to the protocols AML-BFM-78 or -83. Four of them are still alive for more than 5 years, two others died from infections in remission after 1.0 and 3.8 years. Fourteen of the 28 patients in group 2 did not receive any chemotherapy (10 with M7), and subsequently died.(ABSTRACT TRUNCATED AT 250 WORDS)