Sarcoma Subtypes

A comprehensive resource for the sarcoma community.

Currently, there are over 100 recognized histologic sarcoma subtypes. Below is a comprehensive listing of all intermediate and malignant subtypes of sarcoma as recognized by the World Health Organization (WHO). We have included symptoms and causes, diagnosis and treatment, clinical features, latest research, clinical trials, and current research funding opportunities for each subtype.^*

This is meant to be a comprehensive resource for the sarcoma community, especially people diagnosed and living with sarcoma. We designed this so all information needed about a particular subtype can be found in one location.

Please let us know if there is additional information that you would like to see included here. You can email research@curesarcoma.org with your feedback.

^*If a subtype does not include tabs for clinical trials, latest research, or funding opportunities, it is because there is no current information for that subtype. As new research, trial information, or funding opportunities arise, we will update the information listed.

Adamantinoma of Long Bones

Adamantinoma is a biphasic locally aggressive or malignant tumor characterized by a variety of morphological patterns, with a variable epithelial component within a bland osteofibrous component.

Adult Fibrosarcoma

Adult fibrosarcoma is a rare sarcoma composed of relatively monomorphic fibroblastic tumor cells with variable collagen production and often herringbone architecture. It is a diagnosis of exclusion.

Alveolar Rhabdomyosarcoma

Alveolar rhabdomyosarcoma (ARMS) is a malignant neoplasm composed of a monomorphic population of primitive round cells showing skeletal muscle differentiation. The presence of either a PAX3-FOXO1 or a PAX7-FOXO1 fusion gene is detected in the majority of cases.

Alveolar Soft Part Sarcoma

Alveolar soft part sarcoma (ASPS) is a rare tumor of uncertain histogenesis predominantly affecting the deep soft tissues of the extremities, featuring variably discohesive epithelioid cells arranged in nests, resulting in a distinct alveolar appearance. It is characterized by a specific translocation, der(17)t(X;17)(p11.2;q25), which results in ASPSCR1-TFE3 gene fusion.

Angiomatoid Fibrous Histiocytoma

Angiomatoid fibrous histiocytoma (AFH) is a rare neoplasm of intermediate (rarely metastasizing) malignant potential, mostly occurring in subcutis and characterized by varying proportions of epithelioid, ovoid, or spindle cells arranged in a nodular and often syncytial growth pattern, with hemorrhagic pseudovascular spaces and frequently a peripheral fibrous pseudocapsule with a prominent lymphoplasmacytic cuff.

Angiosarcoma

Angiosarcoma is a malignant vascular neoplasm that variably recapitulates the morphological, immunohistochemical features of endothelial cells.

Angiosarcoma of Bone

Angiosarcoma of bone is a high-grade malignant neoplasm of bone demonstrating endothelial differentiation.

Atypical Fibroxanthoma

Atypical fibroxanthoma (AFX) is a dermal-based mesenchymal neoplasm of uncertain differentiation, in a disease spectrum with pleomorphic dermal sarcoma in sun-damaged skin. Tumors that meet strict diagnostic criteria generally behave in a benign fashion.

Atypical Lipomatous Tumor

Atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDLPS) is a locally aggressive mesenchymal tumor with adipocytic proliferation and nuclear atypia in adipocytes and stromal cells. ALT and WDLPS are synonymous, sharing identical morphology and genetics, with nearly all cases showing MDM2 and/or CDK4 amplification.

Central Atypical Cartilaginous Tumor / Chondrosarcoma, Grade 1

Central atypical cartilaginous tumor / chondrosarcoma, grade 1 (ACT/CS1) is a locally aggressive, hyaline cartilage–producing neoplasm arising in the medulla of bone. Tumors in the appendicular skeleton (long and short tubular bones) are termed ACTs, whereas tumors of the axial skeleton (flat bones, including the pelvis, scapula, and skull base) should be called CS1s. Primary conventional central ACT/CS1s are tumors arising centrally within bone without a benign precursor; secondary conventional central ACT/CS1s are tumors arising centrally in bone in association with a pre-existing enchondroma.

Central Chondrosarcoma, Grades 2 and 3

Grade 2 and 3 central chondrosarcomas are central (intramedullary), intermediate-grade (grade 2) and high-grade (grade 3) malignant cartilaginous matrix-producing neoplasms.

CIC-rearranged Sarcoma

CIC-rearranged sarcoma is a high-grade round cell undifferentiated sarcoma defined by CIC-related gene fusions, most often CIC-DUX4.

Clear Cell Chondrosarcoma

Clear cell chondrosarcoma is a low-grade malignant cartilaginous epiphyseal neoplasm characterized by lobules of cells with abundant clear cytoplasm.

Clear Cell Sarcoma of Soft Tissue

Clear cell sarcoma (CCS) of soft tissue is a malignant mesenchymal neoplasm, typically involving deep soft tissue and most often characterized by EWSR1-ATF1 fusion, harboring a distinctive nested growth pattern and melanocytic differentiation.

Composite Haemangioendothelioma

Classic composite haemangioendothelioma (CHE) is a locally aggressive, rarely metastasizing vascular neoplasm, containing an admixture of histologically distinct components. An aggressive form showing neuroendocrine marker expression has also been described.

Conventional Chordoma

Conventional chordoma is a malignant tumor with a phenotype that recapitulates notochord and that usually arises in bones of the axial skeleton.

Dedifferentiated Chondrosarcoma

Dedifferentiated chondrosarcoma is a high-grade subtype of chondrosarcoma with the bimorphic histological appearance of a conventional chondrosarcoma component with abrupt transition to a high-grade, non-cartilaginous sarcoma.

Dedifferentiated Chordoma

Dedifferentiated chordoma is a chordoma with a biphasic appearance, characterized by conventional chordoma and high-grade sarcoma.

Dedifferentiated Liposarcoma

Dedifferentiated liposarcoma (DDLPS) arises from atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDLPS) and progresses to a high-grade, non-lipogenic sarcoma. Most cases show MDM2 and CDK4 amplification, and a well-differentiated component may be absent.

Dermatofibrosarcoma Protuberans

Dermatofibrosarcoma protuberans (DFSP) is a superficial, locally aggressive fibroblastic neoplasm, having a cellular storiform appearance and carrying a COL1A1-PDGFB or related fusion.

Desmoid Fibromatosis

Desmoid fibromatosis is a locally aggressive but non-metastasizing deep-seated (myo)fibroblastic neoplasm with infiltrative growth and propensity for local recurrence.

Desmoplastic Fibroma of Bone

Desmoplastic fibroma of bone is an extremely rare locally aggressive bone tumor composed of bland spindle cells set in abundant collagen, with histology reminiscent of desmoid-type fibromatosis.

Desmoplastic Small Round Cell Tumor

Desmoplastic small round cell tumor (DSRCT) is a malignant mesenchymal neoplasm composed of small round tumor cells associated with prominent stromal desmoplasia, polyphenotypic differentiation, and EWSR1-WT1 gene fusion.

EBV-Associated Smooth Muscle Tumor

EBV-associated smooth muscle tumor is a smooth muscle tumor associated with EBV infection, usually in the setting of immunosuppression.

Ectomesenchymoma

Ectomesenchymoma is an exceedingly rare multiphenotypic sarcoma consisting of both mesenchymal and neuroectodermal lines of differentiation. This biphasic neoplasm is composed of areas resembling rhabdomyosarcoma intermixed with variable neuronal/neuroblastic components.

Embryonal Rhabdomyosarcoma

Embryonal rhabdomyosarcoma (ERMS) is a malignant soft tissue tumor with morphological and immunophenotypic features of embryonic skeletal muscle.

Epithelioid Haemangioendothelioma

Epithelioid haemangioendothelioma is a malignant vascular neoplasm composed of epithelioid endothelial cells within a distinctive myxohyaline stroma; most cases are characterized by the presence of a WWTR1-CAMTA1 gene fusion. A small subset of tumors show distinct morphology, with well-formed vessels lined by epithelioid endothelial cells with abundant eosinophilic cytoplasm, and are characterized by a YAP1-TFE3 fusion.

Epithelioid Haemangioendothelioma of Bone

Epithelioid haemangioendothelioma of bone is a low- to intermediate-grade malignant neoplasm arising from the bone, composed of epithelioid endothelial cells within a distinctive myxohyaline stroma.

Epithelioid Haemangioma of Bone

Epithelioid haemangioma of bone is a locally aggressive vascular neoplasm arising in bone, composed of cells that have an epithelioid morphology and endothelial differentiation.

Epithelioid Sarcoma

Epithelioid sarcoma (ES) is a malignant mesenchymal neoplasm that exhibits partial or complete epithelioid cytomorphology and immunophenotype. Two clinicopathological subtypes are recognized: the classic (or distal) form, characterized by its proclivity for acral sites and pseudogranulomatous growth pattern, and the proximal-type (large cell) subtype, which arises mainly in proximal/truncal regions and consists of nests and sheets of large epithelioid cells.

Ewing Sarcoma

Ewing sarcoma is a small round cell sarcoma showing gene fusions involving one member of the FET family of genes (usually EWSR1) and a member of the ETS family of transcription factors.

Extrarenal Rhabdoid Tumor

Extrarenal rhabdoid tumor is a highly malignant soft tissue tumor, mainly affecting infants and children, that consists of characteristic rounded or polygonal neoplastic cells with glassy eosinophilic cytoplasm containing hyaline-like inclusion bodies, eccentric nuclei, and macronucleoli. Morphologically and genetically identical tumors also arise in the kidney and brain. The majority of tumors are characterized by biallelic alterations of the SMARCB1 gene leading to loss of expression of SMARCB1 (INI1).

Extraskeletal Myxoid Chondrosarcoma

Extraskeletal myxoid chondrosarcoma (EMC) is a malignant mesenchymal neoplasm of uncertain differentiation characterized by abundant myxoid matrix, multilobular architecture, and uniform cells arranged in cords, clusters, and reticular networks. These tumors are characterized by NR4A3 gene rearrangement. Despite the name, there is no evidence of cartilaginous differentiation.

Extraskeletal Osteosarcoma

Extraskeletal osteosarcoma is a malignant tumor characterized by the production of osteoid or bone matrix by neoplastic cells, and it arises without connection to the skeletal system.

Fibrocartilaginous Mesenchymoma

Fibrocartilaginous mesenchymoma is a locally aggressive neoplasm composed of spindle cells with mild cytological atypia, nodules of hyaline cartilage–containing areas resembling growth plate-like cartilage, and bone trabeculae.

Fibrosarcoma of Bone

Fibrosarcoma of bone is a spindle cell malignant neoplasm of bone composed of relatively monomorphic fibroblastic tumor cells with variable collagen production and a fascicular (commonly herringbone) architecture. The diagnosis is one of exclusion.

Gastrointestinal Stromal Tumor

Gastrointestinal stromal tumor (GIST) is a mesenchymal neoplasm with variable behavior, characterized by differentiation towards the interstitial cells of Cajal.

Giant Cell Fibroblastoma

Giant cell fibroblastoma is a locally aggressive fibroblastic neoplasm, closely related to dermatofibrosarcoma protuberans (DFSP), arising primarily in children and characterized by the presence of multinucleated giant cells, pseudovascular spaces, and a COL1A1-PDGFB fusion.

Giant Cell Tumor Of Bone

Giant cell tumor of bone is a locally aggressive and rarely metastasizing neoplasm composed of neoplastic mononuclear stromal cells with a monotonous appearance admixed with macrophages and osteoclast-like giant cells. A small subset of cases are malignant.

Giant Cell Tumor Of Soft Tissue

Giant cell tumor of soft tissue is morphologically similar to but genetically unrelated to giant cell tumor of bone.

Glomus Tumour

Glomus tumor is a mesenchymal neoplasm composed of cells resembling the perivascular modified smooth muscle cells of the normal glomus body.

Granular Cell Tumor

Granular cell tumor is a tumor showing neuroectodermal differentiation and composed of epithelioid to polygonal cells with copious eosinophilic, distinctively granular cytoplasm.

Haemosiderotic Fibrolipomatous Tumor

Haemosiderotic fibrolipomatous tumor (HFLT) is an unencapsulated, locally aggressive neoplasm composed of adipocytes, haemosiderin-laden spindle cells, and haemosiderin-laden macrophages.

High-Grade Surface Osteosarcoma

High-grade surface osteosarcoma is a high-grade malignant bone-forming neoplasm arising on the surface of the bone.

Infantile Fibrosarcoma

Infantile fibrosarcoma (IFS) is a malignant fibroblastic tumor most commonly occurring in infancy, frequently characterized by an ETV6-NTRK3 fusion. It is a locally aggressive and rapidly growing tumor that only rarely metastasizes.

Inflammatory Leiomyosarcoma

Inflammatory leiomyosarcoma (LMS) is a malignant neoplasm showing smooth muscle differentiation, a prominent inflammatory infiltrate, and near-haploidization.

Inflammatory Myofibroblastic Tumour

Inflammatory myofibroblastic tumor (IMT) is a distinctive, rarely metastasizing neoplasm composed of myofibroblastic and fibroblastic spindle cells accompanied by an inflammatory infiltrate of plasma cells, lymphocytes, and/or eosinophils.

Intimal Sarcoma

Intimal sarcomas are malignant mesenchymal tumors arising in large blood vessels of the systemic and pulmonary circulation and also in the heart. The defining feature is predominantly intraluminal growth with obstruction of the lumen of the vessel of origin and seeding of emboli to peripheral organs.

Kaposi Sarcoma

Kaposi sarcoma (KS) is a locally aggressive endothelial proliferation that usually presents with cutaneous lesions in the form of multiple patches, plaques, or nodules, but it may also involve mucosal sites, lymph nodes, and visceral organs. KS is uniformly associated with HHV8 infection, and it represents an example of virus-induced vascular proliferation.

Leiomyosarcoma

Leiomyosarcoma (LMS) is a malignant neoplasm composed of cells showing smooth muscle differentiation.

Leiomyosarcoma of Bone

Leiomyosarcoma (LMS) of bone is a primary malignant neoplasm of bone showing smooth muscle differentiation.

Lipofibromatosis

Lipofibromatosis is a rare, recurrent pediatric soft tissue tumor, often affecting the hands and feet. It features a mix of mature fat, short fascicles of bland spindle cells, and lipoblast-like cells at the interface of the spindle cell and lipomatous components.

Low-Grade Central Osteosarcoma (LGCOS)

Low-grade central osteosarcoma (LGCOS) is a low-grade malignant bone-forming neoplasm that originates within the intramedullary cavity and consists of fibroblastic tumor cells with low-grade nuclear atypia and well-formed neoplastic bony trabeculae.

Low-Grade Fibromyxoid Sarcoma

Low-grade fibromyxoid sarcoma is a malignant fibroblastic neoplasm characterized by alternating collagenous and myxoid areas, deceptively bland spindle cells with a whorling growth pattern, and arcades of small blood vessels. These tumors consistently have either FUS-CREB3L2 or FUS-CREB3L1 gene fusions.

Low-Grade Myofibroblastic Sarcoma

Low-grade myofibroblastic sarcoma is a rarely metastasizing mesenchymal neoplasm, often having fibromatosis-like features, which tends to arise in the head and neck region.

Malignant Melanotic Nerve Sheath Tumor

Malignant melanotic nerve sheath tumor (MMNST) is a rare peripheral nerve sheath tumor composed uniformly of Schwann cells showing melanocytic differentiation, usually arising in association with spinal or autonomic nerves. It is variably associated with Carney complex and frequently shows aggressive clinical behavior. PRKAR1A mutations and loss of PRKAR1A protein expression are seen in the overwhelming majority of cases.

Malignant Peripheral Nerve Sheath Tumour

Malignant peripheral nerve sheath tumor (MPNST) is a malignant spindle cell tumor often arising from a peripheral nerve, from a pre-existing benign nerve sheath tumor, or in a patient with neurofibromatosis type 1 (NF1). In the absence of these settings, particularly in sporadic de novo or radiotherapy-associated tumors, the diagnosis can be more challenging and is based on the histological and immunohistochemical features suggesting Schwannian differentiation.

Mesenchymal Chondrosarcoma

Mesenchymal chondrosarcoma is a high-grade, malignant, biphasic, primitive mesenchymal tumor with a well-differentiated, organized hyaline cartilage component.

Myoepithelioma, Myoepithelial Carcinoma

Myoepithelioma, myoepithelial carcinoma, and mixed tumor are myoepithelial tumors of soft tissue – a group of uncommon neoplasms that share morphological, immunophenotypic, and genetic features with their counterparts in salivary gland and skin. Benign myoepithelial tumors of soft tissue include myoepithelioma and mixed tumor. Malignant myoepithelial tumors of soft tissue are designated myoepithelial carcinomas.

Myxofibrosarcoma

Myxofibrosarcoma comprises a spectrum of malignant fibroblastic neoplasms with variably myxoid stroma, pleomorphism, and a distinctive curvilinear vascular pattern.

Myxoid Liposarcoma

Myxoid liposarcoma (MLPS) is a malignant tumor of uniform round to oval cells with small lipoblasts in a jelly-like stroma and a branching capillary network. It typically has FUS-DDIT3 or, less commonly, EWSR1-DDIT3 fusion transcripts. High-grade, more cellular tumors previously called round cell liposarcoma are included in this category.

Myxoid Pleomorphic Liposarcoma

Myxoid pleomorphic liposarcoma is an exceptionally rare, aggressive adipocytic neoplasm, typically occurring in children and adolescents. Myxoid pleomorphic liposarcoma shows mixed histological features of conventional myxoid liposarcoma and pleomorphic liposarcoma and lacks the gene fusions and amplifications of myxoid liposarcoma, atypical lipomatous tumor, and dedifferentiated liposarcoma.

Myxoinflammatory Fibroblastic Sarcoma

Myxoinflammatory fibroblastic sarcoma (MIFS) is an infiltrative, locally aggressive fibroblastic neoplasm that typically arises in the distal extremities. It is characterized by pleomorphic fibroblastic cells with macronucleoli in a myxohyaline background with a variably prominent inflammatory cell infiltrate.

NTRK-Rearranged Spindle Cell Neoplasm (Emerging)

NTRK-rearranged spindle cell neoplasms (outside infantile fibrosarcomas) represent an emerging group of molecularly defined rare soft tissue tumors, spanning a wide spectrum of morphologies and histological grades and showing frequent coexpression of S100 and CD34 by immunohistochemistry. The tumors are most often characterized by a monomorphic spindle cell phenotype, variable stromal hyalinization, and infiltrative growth. This provisional category includes the recently described lipofibromatosis-like neural tumors and tumors that closely resemble peripheral nerve sheath tumors (PNSTs).

Ossifying Fibromyxoid Tumor

Ossifying fibromyxoid tumor (OFMT) is a rare mesenchymal neoplasm of uncertain differentiation, with cords and trabeculae of ovoid cells embedded in a fibromyxoid matrix, often surrounded by a complete or incomplete peripheral shell of lamellar bone, having potential for local recurrence and metastasis (especially when showing malignant features)

Osteoblastoma

Osteoblastoma is a locally aggressive bone-forming tumor, morphologically similar to osteoid osteoma but with growth potential and generally > 2 cm in dimension.

Osteosarcoma

Osteosarcoma is an intramedullary high-grade sarcoma in which the tumor cells produce bone.

Palmar and Plantar Fibromatosis

Palmar and plantar fibromatoses are benign fibroblastic/myofibroblastic nodules that typically develop in the volar aspect of the hands and fingers or the plantar aponeuroses.

Papillary Intralymphatic Angioendothelioma

Papillary intralymphatic angioendothelioma (PILA) is an uncommon, rarely metastasizing, superficial lymphatic vascular tumor, showing tufting and hobnail endothelial proliferations within lymphatic channel lumina, in a background of lymphatic vascular proliferation or lymphangioma.

Parosteal Osteosarcoma

Parosteal osteosarcoma is a low-grade malignant bone-forming neoplasm that arises on the cortical surface of bone.

PEComa (Perivascular Epithelioid Tumour)

PEComas are mesenchymal neoplasms composed of perivascular epithelioid cells (PECs) – distinctive epithelioid cells that are often closely associated with blood vessel walls and that express both melanocytic and smooth muscle markers.

Perineurioma

Perineuriomas of soft tissue are nearly always benign peripheral nerve sheath tumors composed entirely of perineurial cells. Intraneural and mucosal perineuriomas also exist.

Periosteal Chondrosarcoma

Periosteal chondrosarcoma is a malignant cartilaginous neoplasm that occurs on the surface of bone in close association with the periosteum and invades the underlying cortex or is > 5 cm.

Periosteal Osteosarcoma

Periosteal osteosarcoma is a malignant, predominantly chondroblastic, intermediate-grade bone-forming sarcoma arising on the surface of the bone, typically underneath the periosteum.

Phosphaturic Mesenchymal Tumor

Phosphaturic mesenchymal tumors (PMTs) are morphologically distinctive neoplasms that cause tumor-induced osteomalacia (TIO) in most affected patients, usually through production of FGF23.

Pleomorphic Liposarcoma

Pleomorphic liposarcoma is a pleomorphic, high-grade sarcoma containing variable numbers of pleomorphic lipoblasts. No areas of atypical lipomatous tumor/well-differentiated liposarcoma or other lines of differentiation are present.

Pleomorphic Rhabdomyosarcoma

Pleomorphic rhabdomyosarcoma is a high-grade pleomorphic sarcoma, usually of adults, composed of bizarre brightly eosinophilic polygonal, round, and spindle cells that display skeletal muscle differentiation.

Plexiform Fibrohistiocytic Tumour

Plexiform fibrohistiocytic tumor is a rare dermal and subcutaneous neoplasm showing plexiform architecture and biphasic morphology, composed of nodules of histiocytoid cells and bundles of myofibroblastic spindle cells.

Poorly Differentiated Chordoma

Poorly differentiated chordoma is a poorly differentiated neoplasm with notochordal differentiation, usually arising in the axial skeleton, and characterized by loss of SMARCB1 expression.

Pseudomyogenic Haemangioendothelioma

Pseudomyogenic haemangioendothelioma is a rarely metastasizing endothelial neoplasm that occurs more frequently in young adult males. It often presents as multiple discontiguous nodules in different tissue planes and histologically mimics a myoid tumor or epithelioid sarcoma.

Retiform Haemangioendothelioma

Retiform haemangioendothelioma is a locally aggressive, rarely metastasizing vascular lesion, characterized by distinctive arborizing blood vessels lined by endothelial cells with characteristic hobnail morphology.

Round Cell Sarcoma With EWSR1-Non-ETS Fusions

Round cell sarcomas with EWSR1–non-ETS fusions are round and spindle cell sarcomas with EWSR1 or FUS fusions involving partners unrelated to the ETS gene family.

Sarcoma With BCOR Genetic Alterations

Several groups of primitive round cell sarcomas show BCOR genetic alterations, resulting in oncogenic activation and BCOR overexpression. Although these pathological entities show distinct clinical presentations, there is overlap with regard to morphology, immunoprofile, and gene expression, suggesting a shared pathogenesis. The first group is characterized by sarcomas with BCOR-related gene fusions, most frequently BCOR-CCNB3. The second group shows internal tandem duplication (BCOR-ITD), which has been described in infantile undifferentiated round cell sarcomas and primitive myxoid mesenchymal tumors of infancy.

Sclerosing Epithelioid Fibrosarcoma

Sclerosing epithelioid fibrosarcoma is a rare malignant fibroblastic neoplasm characterized by epithelioid fibroblasts arranged in cords and nests and embedded in a dense sclerotic hyalinized stroma. A subset of sclerosing epithelioid fibrosarcomas are related morphologically and molecularly to low-grade fibromyxoid sarcoma.

Secondary Osteosarcoma

Secondary osteosarcoma is osteosarcoma arising in abnormal bone.

Secondary Peripheral Atypical Cartilaginous Tumor / Chondrosarcoma, Grade 1

Secondary peripheral atypical cartilaginous tumor / chondrosarcoma, grade 1 (ACT/CS1) is a locally aggressive, hyaline cartilage–producing neoplasm arising within the cartilaginous cap of a pre-existing osteochondroma. Tumors in the appendicular skeleton can be called peripheral ACTs, whereas tumors of the axial skeleton (including the pelvis, scapula, and skull base) can be called peripheral CS1s.

Secondary peripheral chondrosarcoma, grades 2 and 3

Grade 2 and 3 secondary peripheral chondrosarcomas are intermediate-grade to high-grade malignant cartilaginous matrix–producing neoplasms originating at the surface of the bone in a pre-existing osteochondroma.

Solitary Fibrous Tumour

Solitary fibrous tumor (SFT) is a fibroblastic tumor characterized by a prominent, branching, thin-walled, dilated (staghorn) vasculature and NAB2-STAT6 gene rearrangement.

Spindle Cell / Sclerosing Rhabdomyosarcoma

Spindle cell / sclerosing rhabdomyosarcoma is a type of rhabdomyosarcoma that has fascicular spindle cell and/or sclerosing morphology.

Superficial CD34-Positive Fibroblastic Tumour

Superficial CD34-positive fibroblastic tumor is a distinctive low-grade neoplasm of the skin and subcutis, characterized by a fascicular to sheet-like proliferation of spindled cells with abundant, eosinophilic, granular to glassy cytoplasm, marked nuclear pleomorphism, a low mitotic count, diffuse CD34 expression, and frequent aberrant keratin immunoreactivity.

Synovial Chondromatosis

Synovial chondromatosis is a locally aggressive neoplasm consisting of multiple hyaline cartilaginous nodules involving the joint space, subsynovial tissue, or tenosynovium (extra-articular subtype). A small subset of cases are malignant.

Synovial Sarcoma

Synovial sarcoma (SS) is a monomorphic blue spindle cell sarcoma showing variable epithelial differentiation. SS is characterized by a specific SS18-SSX1/2/4 fusion gene.

Tenosynovial Giant Cell Tumor

“Tenosynovial giant cell tumor” refers to lesions that arise from the synovium of joints, bursae, and tendon sheaths, exhibiting synovial differentiation. The very uncommon malignant tenosynovial giant cell tumor is defined by the coexistence of a benign tenosynovial giant cell tumor with overtly malignant areas or by recurrence of a typical giant cell tumor as a sarcoma.

Tufted Angioma And Kaposiform Haemangioendothelioma

Kaposiform haemangioendothelioma (KHE) is a rare, often deep-seated, vascular neoplasm usually presenting in children, characterized by lobular infiltrates of capillaries and spindled endothelial cells associated with lymphatic vessels. Tufted angioma (TA), a more superficial lesion, is otherwise essentially identical to KHE. Together, KHE and TA are responsible for virtually all instances of the platelet-trapping syndrome Kasabach–Merritt phenomenon (KMP).

Undifferentiated Pleomorphic Sarcoma

Undifferentiated pleomorphic sarcoma (UPS) is a pleomorphic malignant neoplasm of bone with no identifiable line of differentiation; this is a diagnosis of exclusion.

Undifferentiated Sarcoma

Undifferentiated soft tissue sarcoma (USTS) shows no identifiable line of differentiation when analyzed by presently available technology. At present, this is a heterogeneous group and a diagnosis of exclusion, although genetic subgroups (particularly in the round cell group) have emerged. Not included are dedifferentiated types of specific soft tissue sarcomas (e.g., dedifferentiated liposarcoma), in which the high-grade component is commonly undifferentiated.

Main Content