CDX1 and neoplasm: Subsequently, whole-transcriptome RNA sequencing (RNA-Seq) was performed on the recurrent tumor to assess for any pathogenic gene fusions via Illumina Next Seq using three fusion callers (ChimeraScan, FusionCatcher, and STAR-Fusion) with a maximum read length of 2 x 150 bp and maximum reads per run of up to 1.2 billion. RNA-Seq identified a novel in-frame gene fusion (Figure 3) IRF2BP2::CDX1, resulting from a t(1;5)(q42;q32) translocation, involving exon 1 of the IRF2BP2 gene and exon 2 of the CDX1 gene.