Monosomy 16 as the sole abnormality in myeloid malignancies

The majority of acute myeloid leukemia (AML) and myelodysplastic syndrome ( MDS) patients reported with chromosome 16 abnormalities had the inv(16)(p13 q22) or t(16;16)(p13;q22) rearrangements, which were associated with a favo rable prognosis. in contrast, del(16)(q22) was reported less commonly but w as associated with a less favorable prognosis. We describe an 80-year-old w oman who presented with MDS (refractory anemia). Chromosome analysis from b one marrow aspirate cultures showed monosomy 16 as the sole cytogenetic abn ormality. Comparison of this patient with previously reported cases of mono somy 16 showed that this uncommon abnormality was associated with myeloid d isorders. Monosomy 16 patients, similar to del(16)(q22) patients, tended to be elderly, presented with MDS or AML, and had a poor prognosis. The simil arity in clinical course for del(16)(q22) and monosomy 16 patients suggests that the phenotype in both groups resulted from loss of important gene(s) on 16q, as distinct from the fusion gene product identified in the inv(16) and t(16;16) rearrangements. (C) Elsevier Science Inc., 2000. All rights re served.