Morphological, immunophenotypic and genetic features of an HGBCL, NOS with MYC rearrangement (Case D59). Hematoxylin and eosin stain (A) depicting mild heterogeneity with certain cellular irregularity of the neoplastic cells that are BCL6 positive (B) with partial expression of BCL2 (C). (D) FISH with MYC break-apart shows a signal constellation of 1 colocalization (yellow arrow) and 1 split signal (green and red arrows). (E) Ideogram of the CN, CNN-LOH, and mutational features of this case. Original magnification ×400 (A,C), ×100 (B).