Fig. 4
Case of FET-TFCP2 rhabdomyosarcoma with small nuclear cytomorphology. CT of a multifocal osteolytic lesion of the right femur in the inter-trochanteric area and femoral neck (a, b, coronal reformatted and axial views, respectively) (case TFCP2-7). Core-needle biopsy evidence a mixed proliferation arranged in short fascicles (c) and solid sheets (d). Tumor cells harbor ovoid nuclei with fine chromatin without nucleoli, relatively monomorphic (e). The proliferation stained diffusely for ALK (f), AE1/E3 (g), and MYOD1 (h). A split signal is seen with the FISH assay using a break-apart probe spanning TFCP2 (i). Array-comparative genomic hybridization evidenced copy number alterations across the genome including homozygous deletion of CDKN2A and breakpoint within EWSR1 locus, in keeping with the presence of an underlying EWSR1-TFCP2 fusion (j)
