Cytogenetic analysis of bone marrow cells. (A) G-banding karyotype from a posttreatment (day 88) bone marrow cell showing 47,XX,+8 (arrow indicates trisomy 8). (B) FISH analysis in posttreatment (day 88) bone marrow using ETO (8q22, red; Vysis, Downer's Grove, IL) as a test probe for numerical study of chromosome 8, normalized to acute myeloid leukemia 1 (AML1; 21q22, green; Vysis) as an internal ploidy control probe showing 21.6% of the bone marrow interphase cells with 3 copies of chromosome 8 (arrows). FISH images were captured using a MAX-BX51 Olympus fluorescence microscope (Olympus, Tokyo, Japan) equipped with a 100×/1.30 numerical aperture oil objective. These images were captured and processed using MacProbe software (Applied Imaging, Santa Clara, CA). (C) FISH analysis of a pretreatment bone marrow sample showing trisomy 8 mosaicism. Arrows indicate trisomy 8 interphase nuclei.