Figure 3
(a) FISH using the dual-color 2p23 LSI ALK locus-specific probe on paraffin-embedded section in a primary systemic ALCL (× 1500) showing distinct separation of the red and green signals (arrowheads) indicating a break (rearrangement) in the 2p23 anaplastic lymphoma kinase gene locus. The normal nonrearranged 2p23 locus (arrow) and one rearranged 2p23 locus (arrowheads) are indicated in two representative cells. (b) FISH using the dual-color 2p23 LSI ALK locus-specific probe on paraffin-embedded section in a primary systemic ALCL (× 1500) showing extra nonrearranged 2p23 loci in multiple lymphoma cells (arrows). (c) FISH using a centromeric probe for chromosome 2 on paraffin-embedded section in a primary systemic ALCL (× 1500) with extra nonrearranged 2p23 signals, confirming the presence of trisomy 2 as the cause of extra nonrearranged 2p23 loci in the lymphoma cells (a representative cell with arrow). (d) FISH using the dual-color 2p23 LSI ALK locus-specific probe on paraffin-embedded section in ALK+ B-lineage lymphoma (× 1500) showing rearranged 2p23 loci (arrows).
