Pathology: dermatofibrosarcoma protuberans
Dermatofibrosarcoma protuberans
Cellular; circumscribed; spindle cells with storiform pattern
Pale eosinophilic cytoplasm
Monomorphic ovoid nuclei; occasional mitotic activity
IHC: CD34
RNA-seq: COL1A1::PDGFB gene fusion
Dermatofibrosarcoma protuberans
Spindle cells with storiform pattern
Pale eosinophilic cytoplasm
Monomorphic ovoid nuclei; occasional mitotic activity
RNA-seq: COL1A1::PDGFB gene fusion
Dermatofibrosarcoma protuberans
Aneurysmal; circumscribed; spindle cells with storiform pattern
Pale eosinophilic cytoplasm
Monomorphic ovoid nuclei; occasional mitotic activity
Blood-filled cavity; haemosiderin deposition
RNA-seq: COL1A1::PDGFB gene fusion
Dermatofibrosarcoma protuberans
Cellular; circumscribed; spindle cells with storiform pattern
Pale eosinophilic cytoplasm
Monomorphic ovoid nuclei; occasional mitotic activity
IHC: CD34
RNA-seq: COL1A1::PDGFB gene fusion
Dermatofibrosarcoma protuberans
Infiltrative; spindle-stellate cells with fascicular-storiform pattern
Pale eosinophilic cytoplasm
Monomorphic ovoid nuclei; inconspicuous mitotic activity
IHC: CD34
RNA-seq: COL1A1::PDGFB gene fusion
Dermatofibrosarcoma protuberans
Infiltrative; spindle cells with fascicular-storiform pattern
Pale eosinophilic cytoplasm
Monomorphic ovoid nuclei; occasional mitotic activity
Entrapment of subcutaneous adipose tissue with so-called "honeycomb" pattern
IHC: CD34
RNA-seq: COL1A1::PDGFB gene fusion
Dermatofibrosarcoma protuberans
Infiltrative; spindle-ovoid cells with fascicular-storiform pattern
Pale eosinophilic cytoplasm with indistinct cell borders
Monomorphic ovoid nuclei; inconspicuous mitotic activity
IHC: CD34
RNA-seq: COL6A3::PDGFD gene fusion
PMID: 30014607
Dermatofibrosarcoma protuberans, pigmented (Bednar tumour)
Infiltrative; spindle cells with fascicular-storiform pattern
Pale eosinophilic cytoplasm
Monomorphic ovoid nuclei; occasional mitotic activity
Clusters of elongated cells with dense pigmentation
IHC: CD34
RNA-seq: COL1A1::PDGFB gene fusion
Dermatofibrosarcoma protuberans, myxoid
Protuberant; circumscribed; spindle-stellate cells with fascicular-storiform pattern
Scant eosinophilic cytoplasm
Monomorphic ovoid nuclei with small nucleoli; inconspicuous mitotic activity
IHC: CD34
RNA-seq: COL1A1::PDGFB gene fusion
Dermatofibrosarcoma protuberans, metastatic
Spindle-stellate cells with vague fascicular pattern
Pale eosinophilic cytoplasm
Ovoid nuclei with mild pleomorphism; occasional mitotic activity
Collagenous-myxoid stroma
IHC: CD34
RNA-seq: COL1A1::PDGFB gene fusion
Dermatofibrosarcoma protuberans, metastatic
Spindle-stellate cells with vague fascicular pattern
Pale eosinophilic cytoplasm
Ovoid nuclei with mild pleomorphism; occasional mitotic activity
Collagenous-myxoid stroma
IHC: CD34
RNA-seq: COL1A1::PDGFB gene fusion
Dermatofibrosarcoma protuberans, fibrosarcomatous (fibrosarcoma ex-DFSP)
Cellular; spindle cells with "herringbone" pattern
Pale amphophilic cytoplasm
Ovoid elongated nuclei with mild pleomorphism; conspicuous mitotic activity
RNA-seq: COL1A1::PDGFB gene fusion
Dermatofibrosarcoma protuberans, fibrosarcomatous (fibrosarcoma ex-DFSP)
Cellular; spindle cells with "herringbone" pattern
Pale amphophilic cytoplasm
Ovoid elongated nuclei with mild pleomorphism; conspicuous mitotic activity
IHC: CD34
RNA-seq: COL1A1::PDGFB gene fusion
Dermatofibrosarcoma protuberans, neoadjuvant imatinib
Varied morphology:
Hypocellular spindle cells; sclerotic / hyalinized background
Hypocellular spindle-stellate cells; myxoid background
Hypercellular spindle cells with storiform pattern; scattered nuclear pleomorphism
RNA-seq: COL1A1::PDGFB gene fusion