WGS, read coverage track, and immunohistochemistry. (A) Circos plot with copy number variations, structural variations, and single-nucleotide variants based on WGS data at progression after therapy with CD3xBCMA BsAb. Outer track runs clockwise from chromosome 1 to Y. Inner track shows gains >1 Mb in blue and losses >1 Mb in red. Red lines inside the circle represent interchromosomal translocations with variant allele frequency (VAF) >0.1. Genes with mutations (CRBN) are depicted in red. (B) Read coverage visualized with Integrative Genomics Viewer illustrates copy number variations in the short arm of chromosome 16 comprising heterozygous deleted regions caused by monosomy 16 and a homozygous deletion of 586 kb from 12.036.001 to 12.622.000 (hg19 reference genome) including TNFRSF17 (BCMA ). (C) BCMA protein expression was determined by immunohistochemistry using a polyclonal goat anti-BCMA antibody on paraffin-embedded bone marrow sections. Lambda light chain staining (immunohistochemistry) served as positive control (magnification, x200).