Case 2 (A) Bone marrow aspirates from patient 2. Large, round nucleus with a blocky chromatin pattern with a prominent nucleolus (red arrow). Basophil (blue arrow) (Wright stain, ×1,000). (B) Karyotype of patient 2: 46,XY,t(4;12)(q12;p13)[13]. (C) FISH analysis using an XL FIP1L1/CHIC2/PDGFRA probe showed 2 orange/green fusions and 1 green signal (arrow). (D) FISH analysis using a Vysis LSI ETV6/RUNX1 ES probe showed 3 green and 2 orange signals in interphase and metaphase cells, revealing an ETV6 rearrangement. (E) FISH analysis using an XL del(7)(q22q31) tri-color probe showed 2 aqua, 2 green, and 2 orange signals at the initial diagnosis. (F) FISH analysis using an XL del(7)(q22q31) tri-color probe showed 2 aqua, 1 green, and 1 orange signal at the follow-up, showing deletion signals for 7q22-7q31.