Fig. 2

Lymphoid infiltrate with follicular architecture (A inset), characterized by large centroblasts with few, centrocytes (A). The lymphoid cells were positive for CD10 (B) with remnants of the FDC meshwork highlighted by CD21 (C) staining. BCL6 (D), BCL2 (E) were also positive. The atypical cells exhibited MYC protein (F). Fluorescent in-situ hybridization (FISH) studies detected both IGH/BCL2 (G) and IGH/MYC (H) gene rearrangements in approximately 60% of interphase nuclei with dual-colour break-apart probes (G–H, Yellow arrows: normal alleles; red and green arrows: breakages). [original magnification: A inset, B–F: × 40; A: × 400; G,H: × 1000]