CLINICAL TRIALS AND OBSERVATIONS Outcome of patients with acute myeloid leukemia with monosomal karyotype who undergo hematopoietic cell transplantation

Monosomal karyotype (MK), defined as > 2 autosomal monosomies or a single monosomy in the presence of other structural abnormalities, was confirmed by several studies to convey an extremely poor prognosis in patients with acute myeloid leukemia (AML) with a 4-year overall survival after diagnosis of < 4%. A recent investigation by the Southwest Oncology Group found that the only MK patients alive and disease free > 6 years from diagnosis received allogeneic hematopoietic cell transplantation (HCT). To expand this observation, we retrospectively analyzed 432 patients treated with HCT at the Fred Hutchinson Cancer Research Center, 14% of whom were MK . The 4-year overall survival of patients after HCT was 25% for MK AML and 56% for MK AML (adjusted hazard ratio 2.29, P < .0001). Among the MK patients, complex karyotype was associated with a significantly worse outcome than patients with noncomplex karyotype (adjusted hazard ratio 2.70, P .03). Thus, although the prognosis of MK patients remains worse than that for MK patients in the transplantation setting, HCT appears to improve the overall outcome of MK patients, especially patients without a complex karyotype. However, the 28% of MK patients > 60 years had only a 6% 4-year survival rate after HCT, stressing the need for new approaches in these patients. (Blood. 2011;118(6):1490-1494)