WHO classification of tumors of soft tissue

The WHO 2002 classification of soft tissue tumours is as follows:

This however has been revised under the 2013 WHO tissue tumour classification system⁴.

Adipocytic tumours

Benign

• lipoma 8850/0*
• lipomatosis 8850/0
• lipomatosis of nerve 8850/0
• lipoblastoma/lipoblastomatosis 8881/0
• angiolipoma 8861/0
• myolipoma 8890/0
• chondroid lipoma 8862/0
• extrarenal angiomyolipoma 8860/0
• extra-adrenal myelolipoma 8870/0
• spindle cell lipoma 8857/0
• pleomorphic lipoma 8854/0
• hibernoma 8880/0

Intermediate (locally aggressive)

• atypical lipomatous tumour/well differentiated liposarcoma 8851/3

Malignant

• liposarcoma:
  • dedifferentiated liposarcoma 8858/3
  • myxoid liposarcoma 8852/3
  • round cell liposarcoma 8853/3
  • pleomorphic liposarcoma 8854/3
  • mixed-type liposarcoma 8855/3
  • liposarcoma, not otherwise specified 8850/3

Fibroblastic/myofibroblastic tumours

Benign

• nodular fasciitis
• proliferative fasciitis
• proliferative myositis
• myositis ossificans
• fibro-osseous pseudotumour of digits
• ischaemic fasciitis
• elastofibroma 8820/0
• fibrous hamartoma of infancy
• myofibroma/myofibromatosis 8824/0
• fibromatosis colli
• juvenile hyaline fibromatosis
• inclusion body fibromatosis
• fibroma of tendon sheath 8810/0
• desmoplastic fibroblastoma 8810/0
• mammary-type myofibroblastoma 8825/0
• calcifying aponeurotic fibroma 8810/0
• angiomyofibroblastoma 8826/0
• cellular angiofibroma 9160/0
• nuchal-type fibroma 8810/0
• Gardner fibroma 8810/0
• calcifying fibrous tumour
• giant cell angiofibroma 9160/0

Intermediate (locally aggressive)

• superficial fibromatoses (palmar/plantar)
• desmoid-type fibromatoses 8821/1
• lipofibromatosis

Intermediate (rarely metastasising)

• solitary fibrous tumour 8815/1
• and haemangiopericytoma 9150/1(incl. lipomatous haemangiopericytoma)
• Inflammatory myofibroblastic tumour 8825/1
• low grade myofibroblastic sarcoma 8825/3
• myxoinflammatory
  • fibroblastic sarcoma 8811/3 (myxoinflammatory fibroblastic sarcoma)
  • infantile fibrosarcoma 8814/3

Malignant

• adult fibrosarcoma 8810/3
• myxofibrosarcoma 8811/3
• low grade fibromyxoid sarcoma 8811/3
• hyalinizing spindle cell tumour
• sclerosing epithelioid fibrosarcoma 8810/3

So called fibrohistiocytic tumours

Benign

• giant cell tumour of tendon sheath 9252/0
• diffuse-type giant cell tumour 9251/0
• deep benign fibrous histiocytoma 8830/0

Intermediate (rarely metastasising)

• plexiform fibrohistiocytic tumour 8835/1
• giant cell tumour of soft tissues 9251/1

Malignant

• pleomorphic ‘MFH’/undifferentiated pleomorphic sarcoma 8830/3
• giant cell ‘MFH’/undifferentiated pleomorphic sarcoma with giant cells 8830/3
• inflammatory ‘MFH’/undifferentiated pleomorphic sarcoma withprominent inflammation 8830/3

Smooth muscle tumours

• angioleiomyoma 8894/0
• deep leiomyoma 8890/0
• genital leiomyoma 8890/0
• leiomyosarcoma (excluding skin) 8890/3

Pericytic (perivascular) tumours

• glomus tumour (and variants) 8711/0
• malignant glomus tumour 8711/3
• myopericytoma 8713/1

Skeletal muscle tumours

Benign

• rhabdomyoma 8900/0
  • adult type 8904/0
  • fetal type 8903/0
  • genital type 8905/0

Malignant

• embryonal rhabdomyosarcoma 8910/3
• (incl. spindle cell, 8912/3
• botryoid (anaplastic) 8910/3
• alveolar rhabdomyosarcoma (incl. solid, anaplastic) 8920/3
• pleomorphic rhabdomyosarcoma 8901/3

Vascular tumours

Benign

• haemangiomas of subcutaenous/deep soft tissue: 9120/0
• capillary haemangioma 9131/0
• cavernous haemangioma 9121/0
• arteriovenous haemangioma 9123/0
• venous haemangioma 9122/0
• intramuscular haemangioma 9132/0
• synovial haemangioma 9120/0
• epithelioid haemangioma 9125/0
• angiomatosis
• lymphangioma 9170/0

Intermediate (locally aggressive)

• Kaposiform haemangioendothelioma 9130/1

Intermediate (rarely metastasizing)

• retiform haemangioendothelioma 9135/1
• papillary intralymphatic angioendothelioma 9135/1
• composite haemangioendothelioma 9130/1
• Kaposi sarcoma 9140/3

Malignant

• epithelioid haemangioendothelioma 9133/3
• angiosarcoma of soft tissue 9120/3

Chondro-osseous tumours 

• soft tissue chondroma 9220/0
• mesenchymal chondrosarcoma 9240/3
• extraskeletal osteosarcoma 9180/3

Tumours of uncertain differentiation 

Benign

• intramuscular myxoma 8840/0 (incl. cellular variant)
• juxta-articular myxoma 8840/0
• deep (‘aggressive’) angiomyxoma 8841/0
• pleomorphic hyalinizing angiectatic tumour
• ectopic hamartomatous thymoma 8587/0

Intermediate (rarely metastasizing)

• angiomatoid fibrous histiocytoma 8836/1
• ossifying fibromyxoid tumour 8842/0 (incl. atypical/malignant)
• mixed tumour 8940/1
• myoepithelioma 8982/1
• parachordoma 9373/1

Malignant

• synovial sarcoma 9040/3
• epithelioid sarcoma 8804/3
• alveolar soft part sarcoma 9581/3
• clear cell sarcoma of soft tissue 9044/3
• extraskeletal myxoid chondrosarcoma 9231/3 ("chordoid" type)
• PNET/extraskeletal Ewing tumour
• pPNET 9364/3
• extraskeletal Ewing tumour 9260/3
• desmoplastic small round cell tumour 8806/3
• extra-renal rhabdoid tumour 8963/3
• malignant mesenchymoma 8990/3
• neoplasms with perivascular epithelioid cell differentiation (PEComa)
• clear cell myomelanocytic tumour
• intimal sarcoma 8800/3