Acute Megakaryoblastic Leukemia: Importance of Bone Marrow Biopsy in Diagnosis

Acute myelogenous leukemia in Down's syndrome: report of a single pediatric institution using a BFM treatment strategy

Between July 1990 and December 1995, 111 new consecutive pediatric patients with acute myelogenous leukemia (AML) have been treated in our institution. Eleven of them (9.9%) had Down's syndrome (DS), 6 boys and 5 girls. The median age was 22.5 (range 10-40) months. FAB subtypes were the following: M7: 6, M4: 3, and M0: 2. Five of them had previously had myelodysplasia and in 3, all FAB M7, myelofibrosis was detected. This population was treated with two consecutive protocols. Nine patients were included in the AML-HPG-90 protocol and 2 patients in the AML-HPG-95 study, respectively. However, all DS patients in this series received the same treatment. Eight patients achieved complete remission: two patients received two cycles of intensification with high dose (HD) ara-C, and 1 patient, only one cycle; the other 5 were prevented from receiving such therapy because of unacceptable toxicity or death. At 45 months, event-free survival and overall survival estimates were 0.30, S.E. 0.16. Mortality was remarkably high. All deaths (7) were associated with sepsis (5) or pulmonary infection (2). Three deaths occurred before achieving complete remission, 3 patients died during the consolidation phase and 1 died whilst off treatment. No one presented leukemic relapse. We conclude that this AML-BFM treatment strategy is highly toxic to children with DS and AML in our setting. Efforts will be made to improve clinical support and to administer less intensive therapy to this particular pediatric AML subgroup, which, in fact, has a better prognosis than the same non-trisomic population.

Transient myeloproliferative disorder associated with trisomy 21, a wide range syndrome: report of two cases with trisomy 21 mosaicism

Transient myeloproliferative disorder (TMD) is an uncommon syndrome strongly associated with abnormalities of chromosome 21. Blast transient proliferation appears most frequently at neonatal age and usually resolves spontaneously in two or three months. Two patients, a girl and a boy, with neonatal onset of TMD are reported. They both presented trisomy 21 mosaicism according to bone marrow cytogenetic analysis. Patient 1, on one end of the spectrum, showed a "classic" benign course with rapid resolution and favorable outcome. Patient 2, on the other hand, had two blast outbursts both followed by spontaneous remissions. He failed to thrive and never reached a good general condition, dying at 5 months of age from a respiratory infectious complication. The necropsy showed generalized extramedullary hemopoiesis without evidence of bone marrow blast infiltration or myelofibrosis. TMD has some clinical and laboratory features that make it unique and distinguishable from true congenital leukemia with which it may be initially mistaken. It usually has a benign course followed by a favorable outcome. As trisomy 21 mosaicism may not have overt phenotypic stigmata, it is possible that many cases of TMD in these children may have a silent, non-detected course. We also conclude that a favorable outcome is not always to be expected in TMD.