Pathology: low-grade fibromyxoid sarcoma

Low-grade fibromyxoid sarcoma

  • Hypocellular; spindle cells with loose fascicular-storiform pattern

  • Pale eosinophilic cytoplasm with long tapering processes

  • Monomorphic ovoid nuclei; inconspicuous mitotic activity

  • Prominent myxoid stroma; condensation of tumour around delicate curvilinear vessels

  • IHC: MUC4

  • RNA-seq: FUS::CREB3L2 gene fusion

Low-grade fibromyxoid sarcoma

  • Hypocellular; spindle cells with loose fascicular-storiform pattern

  • Pale eosinophilic cytoplasm with long tapering processes

  • Monomorphic ovoid nuclei; inconspicuous mitotic activity

  • Prominent fibromyxoid stroma; condensation of tumour around delicate curvilinear vessels

  • IHC: MUC4

  • RNA-seq: FUS::CREB3L2 gene fusion


Low-grade fibromyxoid sarcoma

  • Hypocellular; spindle cells with loose fascicular-storiform pattern

  • Pale eosinophilic cytoplasm with long tapering processes

  • Monomorphic ovoid nuclei; inconspicuous mitotic activity

  • Prominent fibrous stroma; occasional ectatic thin-walled vessels

  • RNA-seq: FUS::CREB3L2 gene fusion


Low-grade fibromyxoid sarcoma

  • Hypocellular; spindle-stellate cells with loose fascicular-storiform pattern

  • Pale eosinophilic cytoplasm with delicate tapering processes

  • Monomorphic ovoid nuclei; inconspicuous mitotic activity

  • Prominent myxoid stroma; occasional short thin-walled vessels

  • RNA-seq: FUS::CREB3L2 gene fusion

Low-grade fibromyxoid sarcoma

  • Hypocellular; spindle-stellate cells with loose fascicular-storiform pattern

  • Pale eosinophilic cytoplasm with delicate tapering processes

  • Monomorphic ovoid nuclei; inconspicuous mitotic activity

  • Prominent myxoid stroma; occasional short thin-walled vessels

  • IHC: MUC4

Low-grade fibromyxoid sarcoma

  • Cellular; spindle-epithelioid cells with vague fascicular pattern

  • Pale eosinophilic cytoplasm

  • Monomorphic ovoid nuclei; occasional mitotic activity

  • Areas of fibrous stroma; delicate curvilinear vasculature

  • IHC: MUC4

  • RNA-seq: FUS::CREB3L1 gene fusion

Low-grade fibromyxoid sarcoma

  • Cellular; spindle-epithelioid cells with vague fascicular pattern

  • Pale eosinophilic cytoplasm

  • Monomorphic ovoid nuclei; inconspicuous mitotic activity

  • Areas of fibrous stroma; delicate curvilinear vasculature

  • IHC: MUC4

  • RNA-seq: FUS::CREB3L2 gene fusion

Low-grade fibromyxoid sarcoma

  • Lobulated; variable cellularity; spindle-epithelioid cells with vague fascicular pattern

  • Pale eosinophilic cytoplasm

  • Monomorphic ovoid nuclei; occasional mitotic activity

  • Prominent hyalinized stroma forming so-called "pseudorosettes"; delicate curvilinear vasculature

  • IHC: MUC4

  • FISH: FUS-rearrangement

  • PMID: 9414192