Impact of trisomy 8 (+8) on clinical presentation, treatment response, and survival in acute myeloid leukemia: a Southwest Oncology Group study.

The prognostic impact of trisomy 8, alone or with other clonal aberrations, was evaluated in 849 patients with previously untreated acute myeloid leukemia (AML) who were registered to 5 Southwest Oncology Group trials. At presentation, 108 (12.7%) patients had +8 in their karyotypes, including 43 (5.1%) patients with +8 as the sole aberration; 307 (36.2%) were normal, and 434 (51.1%) had other cytogenetic abnormalities. Patients with +8 were slightly older (P =.033), had lower WBC (P =.011), and had lower percentages of peripheral blasts (P =.0004) than the patients without +8. Median survival time for all patients with +8 was 9.9 months (95% CI, 6.5-12.5), similar to that of "unfavorable" cytogenetics risk groups (8.3 months; 95% CI, 6.8-9.5.) Patients with +8 had significantly lower peripheral blasts (P =.0002), WBC (P <.0001) counts, and decreased overall survival (OS) than patients with normal cytogenetics (9.9 months vs 15.4 months; P =.006). However, survival of patients with +8 as the sole aberration did not differ significantly from those with normal cytogenetics (P =.36). Thus, the trisomy 8 group as a whole had poor survival, which was largely attributable to worsened outcomes among patients whose trisomy 8 was associated with other unfavorable cytogenetic abnormalities.