Pathology: spindle cell / sclerosing rhabdomyosarcoma
Rhabdomyosarcoma, spindle cell
Spindle cells in storiform-fascicular pattern
Pale eosinophilic cytoplasm
Ovoid nuclei with vesicular chromatin, and mild pleomorphism; inconspicuous mitotic activity
IHC: desmin, myogenin
RNA-seq: CITED2-rearrangementÂ
Rhabdomyosarcoma, spindle cell
Spindle-epithelioid cells in fascicles
Abundant eosinophilic cytoplasmÂ
Round-ovoid nuclei with prominent nucleoli and moderate pleomorphism; conspicuous mitotic activity
Interspersed rhabdomyoblasts
IHC: desmin, myogenin, keratin (AE1/AE3)Â
Rhabdomyosarcoma, spindle cell
Spindle-epithelioid cells in fascicles
Abundant eosinophilic cytoplasmÂ
Round-ovoid nuclei with prominent nucleoli and moderate pleomorphism; conspicuous mitotic activity
IHC: desmin, myogenin, keratin (AE1/AE3)Â
RNA-seq: FUS::TFCP2 gene fusion
PMID: 29431183, 36374445
Rhabdomyosarcoma, spindle cell
Spindle cell fascicles with variable cellularity
Abundant eosinophilic cytoplasm with bipolar processes
Ovoid monomorphic nuclei; conspicuous mitotic activity
Areas of myxoid stroma, particularly around vessels
IHC: desminÂ
RNA-seq: ZFP64::NCOA3 gene fusion
PMID: 35521817
Rhabdomyosarcoma, spindle cell
Spindle cell fascicles with variable cellularity
Abundant eosinophilic cytoplasm with bipolar processes
Ovoid monomorphic nuclei; inconspicuous mitotic activity
IHC: desmin, MyoD1; (myogenin negative)
RNA-seq: ZFP64::NCOA3 gene fusion
PMID: 35521817
Rhabdomyosarcoma, spindle cell
Hypocellular spindle cell fascicles
Abundant eosinophilic cytoplasm with bipolar processes
Ovoid monomorphic nuclei; inconspicuous mitotic activity
Areas of hyalinization, particularly around vessels
IHC: desmin, MyoD1; (myogenin negative)
RNA-seq: ZFP64::NCOA3 gene fusion
PMID: 35521817
Rhabdomyosarcoma, spindle cell
Short spindle cell fascicles; infiltrating native skeletal muscle
Scant eosinophilic cytoplasm with bipolar processes
Ovoid monomorphic nuclei; inconspicuous mitotic activity
IHC: desmin, myogenin
RNA-seq: PPARGC1A::VGLL3 gene fusion
PMID: 35766997
Rhabdomyosarcoma, spindle cell
Short spindle cell fascicles; infiltrating native skeletal muscle
Scant eosinophilic cytoplasm with bipolar processes
Ovoid monomorphic nuclei; inconspicuous mitotic activity
IHC: desmin, myogenin
RNA-seq: EP300::VGLL3 gene fusion
PMID: 35766997
Rhabdomyosarcoma, spindle cell
Infiltrative
Polygonal-spindle cells with vague fascicular-storiform pattern
Eosinophilic cytoplasm
Ovoid nuclei with occasional multinucleation and moderate pleomorphism; mitotic activity
IHC: desmin, myogenin
RNA-seq: EP300::VGLL3 gene fusion
PMID: 35766997
Rhabdomyosarcoma, spindle cell
Spindle cell fascicles
Eosinophilic cytoplasmÂ
Ovoid-elongated nuclei with prominent nucleoli and mild pleomorphism; occasional mitotic activity
Interspersed rhabdomyoblasts with abundant dense eosinophilic cytoplasm and multiple nuclei; occasional thin-walled and ectatic vessels
IHC: desmin, myogenin
Rhabdomyosarcoma, spindle cell
Spindle cell fascicles
Pale amphophilic cytoplasm
Hyperchromatic ovoid-elongated nuclei with prominent nucleoli and mild pleomorphism; occasional mitotic activity
Interspersed collagenous stroma
IHC: desmin, myogenin
Rhabdomyosarcoma, spindle cell
Spindle cell fascicles
Pale amphophilic cytoplasm with indistinct cell borders
Hyperchromatic ovoid-elongated nuclei with mild pleomorphism; occasional mitotic activity
Interspersed rhabdomyoblasts with abundant dense eosinophilic cytoplasm; multiple peripheral nuclei; myxoid-collagenous stroma; ectatic thin-walled vasculature
IHC: desmin, myogenin