AMKL associated with Down syndrome (DS-AMKL) has a superior outcome compared with the sporadic form, with long-term survival [3, 19].
Acute megakaryoblastic leukaemia (AMKL) and transient myeloproliferative disorder (TMD) in Down syndrome: a multi-step model of myeloid leukaemogenesis.
The presence of an acquired mutation(s) in exon 2 or exon 3 of the GATA1 gene on chromosome X establishes a diagnosis of TAM and serves as a potential marker for future disease monitoring in the development of AMKL. If a GATA1 mutation is detected in a neonate without clinical features of DS, cytogenetic analysis should still be performed to exclude DS mosaicism.
Approximately 20% of patients with TAM develop AMKL within the first 4 years of life and this may be preceded by a myelodysplastic-like syndrome.
By 5 years of age, 20% of patients progress to AMKL following an intervening remission and/or a preceding myelodysplastic-like syndrome.
Here we present five cases of AMKL with their clinico haematological, morphological; cytochemical features and discuss diagnostic difficulties/clue to arrive at definitive diagnosis.
DISCUSSION: AMKL is a rare leukemia accounting for 7-10% of Childhood AML (7) & 1-2 % of adult AML (8, 9) and have a poor prognosis.
Patients with Down syndrome have increased incidence of AMKL & have a good prognosis.
Careful search for features like cytoplasmic blebbing, platelet budding, clustering of blasts & cytochemical PAS positivity for cytoplasmic blebs can help in correct diagnosis of AMKL.
INDEX TERMS: acute megakaryoblastic leukemia (M7, AMKL); acute myelogenous leukemia (AML); Down syndrome.
4 AML in Down syndrome is usually a specific type of acute megakaryoblastic leukemia (M7, AMKL).
CD61, which stains positively in disease states of AMKL and also stains positive for blasts in transient myeloproliferative disorder, demonstrated a weak 1+.