TRISOMY-19 AS THE SOLE CHROMOSOMAL ANOMALY IN HEMATOLOGIC NEOPLASMS

Trisomy 19 was found as the sole chromosomal aberration in three hematologic malignancies: one chronic myelomonocytic leukemia and two cases of immunophenotypically immature acute myeloid leukemia (AML). A compilation of previously published hematologic neoplasms with +19 as the only change reveals that this anomaly is strongly associated with myeloid malignancies; 25 of 31 cases have been myelodysplastic syndromes (MDS) or AML. Eight of the 11 MDS cases have been either refractory anemia (RA) or RA with excess of blasts, and four of the 14 AML cases have had a preleukemic myelodysplastic phase, with the +19 accruing during the time of leukemic transformation. The AML cases have, in general, been either of early maturation arrest, i.e., undifferentiated or AML-M1/M2, or of myelomonocytic-monoblastic origin, i.e., AML-M4/M5. None of the MDS or AML cases with +19 has had a previous history of radio- or chemotherapy. We conclude that trisomy 19, as the sole anomaly, is a characteristic abnormality in de novo myeloid malignancies. No clinical features seem to characterize patients with +19 AML and MDS and the prognostic impact of the aberration remains to be elucidated.