Appendix 1: WHO Classification

Tumours of the nasal cavity, paranasal sinuses and skull base

Carcinomas

  • Keratinizing squamous cell carcinoma
  • Non-keratinizing squamous cell carcinoma
  • Spindle cell (sarcomatoid) squamous cell carcinoma
  • Lymphoepithelial carcinoma
  • Sinonasal undifferentiated carcinoma
  • NUT carcinoma
  • Neuroendocrine carcinoma
  • Adenocarcinoma
    • Intestinal-type adenocarcinoma
    • Non–intestinal-type adenocarcinoma

Teratocarcinosarcoma

Sinonasal papillomas

  • Sinonasal papilloma, inverted type
  • Sinonasal papilloma, oncocytic type
  • Sinonasal papilloma, exophytic type

Respiratory epithelial lesions

  • Respiratory epithelial adenomatoid hamartoma
  • Seromucinous hamartoma

Salivary gland tumours

  • Pleomorphic adenoma

Malignant soft tissue tumours

  • Fibrosarcoma
  • Undifferentiated pleomorphic sarcoma
  • Leiomyosarcoma
  • Rhabdomyosarcoma
  • Angiosarcoma
  • Malignant peripheral nerve sheath tumour
  • Biphenotypic sinonasal sarcoma
  • Synovial sarcoma

Borderline / low-grade malignant soft tissue tumours

  • Desmoid-type fibromatosis
  • Sinonasal glomangiopericytoma
  • Solitary fibrous tumour
  • Epithelioid haemangioendothelioma

Benign soft tissue tumours

  • Leiomyoma
  • Haemangioma
  • Schwannoma
  • Schwannoma

Other tumours

  • Meningioma
  • Sinonasal ameloblastoma
  • Chondromesenchymal hamartoma

Haematolymphoid tumours

  • Extranodal NK/T-cell lymphoma
  • Extraosseous plasmacytoma

Neuroectodermal / melanocytic tumours

  • Ewing sarcoma / primitive neuroectodermal tumours
  • Olfactory neuroblastoma
  • Mucosal melanoma

Tumours of the nasopharynx

Nasopharyngeal carcinoma

Nasopharyngeal papillary adenocarcinoma

Salivary gland tumours

  • Adenoid cystic carcinoma
  • Adenoid cystic carcinoma

Benign and borderline lesions

  • Hairy polyp
  • Ectopic pituitary adenoma
  • Craniopharyngioma

Soft tissue tumours

  • Nasopharyngeal angiofibroma

Haematolymphoid tumours

Notochordal tumours

  • Chordoma

Tumours of the hypopharynx, larynx, trachea and parapharyngeal space

Malignant surface epithelial tumours

  • Conventional squamous cell carcinoma
  • Verrucous squamous cell carcinoma
  • Basaloid squamous cell carcinoma
  • Papillary squamous cell carcinoma
  • Spindle cell squamous cell carcinoma
  • Adenosquamous carcinoma
  • Lymphoepithelial carcinoma

Precursor lesions

  • Dysplasia
  • Squamous cell papilloma & squamous cell papillomatosis

Neuroendocrine tumours

  • Well-differentiated neuroendocrine carcinoma
  • Moderately differentiated neuroendocrine carcinoma
  • Poorly differentiated neuroendocrine carcinoma

Salivary gland tumours

  • Adenoid cystic carcinoma
  • Pleomorphic adenoma
  • Oncocytic papillary cystadenoma

Soft tissue tumours

  • Granular cell tumour
  • Liposarcoma
  • Inflammatory myofibroblastic tumour

Cartilage tumours

  • Chondroma and chondrosarcoma

Haematolymphoid tumours

Tumours of the oral cavity and mobile tongue

Malignant surface epithelial tumours

  • Squamous cell carcinoma

Oral potentially malignant disorders & oral epithelial dysplasia

  • Oral potentially malignant disorders
  • Oral epithelial dysplasia
  • Proliferative verrucous leukoplakia

Papillomas

  • Squamous cell papilloma
  • Condyloma acuminatum
  • Verruca vulgaris
  • Multifocal epithelial hyperplasia

Tumours of uncertain histogenesis

  • Congenital granular cell epulis
  • Ectomesenchymal chondromyxoid tumour

Soft tissue and neural tumours

  • Granular cell tumour
  • Rhabdomyoma
  • Lymphangioma
  • Haemangioma
  • Schwannoma and neurofibroma
  • Kaposi sarcoma
  • Myofibroblastic sarcoma

Oral mucosal melanoma

Salivary type tumours

  • Mucoepidermoid carcinoma
  • Pleomorphic adenoma

Haematolymphoid tumours

  • CD30-positive T-cell lymphoproliferative disorder
  • Plasmablastic lymphoma
  • Langerhans cell histiocytosis
  • Extramedullary myeloid sarcoma

Tumours of the oropharynx (base of tongue, tonsils, adenoids)

Squamous cell carcinoma

  • Squamous cell carcinoma, HPV-positive
  • Squamous cell carcinoma, HPV-negative

Salivary gland tumours

  • Pleomorphic adenoma
  • Adenoid cystic carcinoma
  • Polymorphous adenocarcinoma

Haematolymphoid tumours

  • Hodgkin lymphoma
  • Burkitt lymphoma
  • Follicular lymphoma
  • Mantle cell lymphoma T-lymphoblastic leukaemia/lymphoma
  • Follicular dendritic cell sarcoma

Tumours and tumour-like lesions of the neck and lymph nodes

Tumours of unknown origin

  • Carcinoma of unknown primary
  • Merkel cell carcinoma
  • Heterotopia-associated carcinoma

Haematolymphoid tumours

Cysts and cyst-like lesions

  • Branchial cleft cyst
  • Thyroglossal duct cyst
  • Ranula
  • Dermoid and teratoid cysts

Tumours of salivary glands

Malignant tumours

  • Mucoepidermoid carcinoma
  • Adenoid cystic carcinoma
  • Acinic cell carcinoma
  • Polymorphous adenocarcinoma
  • Clear cell carcinoma
  • Basal cell adenocarcinoma
  • Intraductal carcinoma
  • Adenocarcinoma, NOS
  • Salivary duct carcinoma
  • Myoepithelial carcinoma
  • Epithelial–myoepithelial carcinoma
  • Carcinoma ex pleomorphic adenoma
  • Secretory carcinoma
  • Sebaceous adenocarcinoma
  • Carcinosarcoma
  • Poorly differentiated carcinoma
  • Lymphoepithelial carcinoma
  • Squamous cell carcinoma
  • Oncocytic carcinoma
  • Sialoblastoma

Benign tumours

  • Pleomorphic adenoma
  • Myoepithelioma
  • Basal cell adenoma
  • Warthin tumour
  • Oncocytoma
  • Lymphadenoma
  • Cystadenoma
  • Sialadenoma papilliferum
  • Ductal papillomas
  • Sebaceous adenoma
  • Canalicular adenoma and other ductal adenomas

Non-neoplastic epithelial lesions

  • Sclerosing polycystic adenosis
  • Nodular oncocytic hyperplasia
  • Lymphoepithelial sialadenitis
  • Intercalated duct hyperplasia

Benign soft tissue lesions

  • Haemangioma
  • Lipoma/sialolipoma
  • Nodular fasciitis

Haematolymphoid tumours

  • Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma)

Odontogenic and maxillofacial bone tumours

Odontogenic carcinomas

  • Ameloblastic carcinoma
  • Primary intraosseous carcinoma, NOS
  • Sclerosing odontogenic carcinoma
  • Clear cell odontogenic carcinoma
  • Ghost cell odontogenic carcinoma

Odontogenic carcinosarcoma

Odontogenic sarcomas

Benign epithelial odontogenic tumours

  • Ameloblastoma
    • Ameloblastoma, unicystic type
    • Ameloblastoma, extraosseous/peripheral type
    • Metastasizing ameloblastoma
  • Squamous odontogenic tumour
  • Calcifying epithelial odontogenic tumour
  • Adenomatoid odontogenic tumour

Benign mixed epithelial & mesenchymal odontogenic tumours

  • Ameloblastic fibroma
  • Primordial odontogenic tumour
  • Odontoma
  • Dentinogenic ghost cell tumour

Benign mesenchymal odontogenic tumours

  • Odontogenic fibroma
  • Odontogenic myxoma/myxofibroma
  • Cementoblastoma
  • Cemento-ossifying fibroma

Odontogenic cysts of inflammatory origin

  • Radicular cyst
  • Inflammatory collateral cysts

Odontogenic and non-odontogenic developmental cysts

  • Dentigerous cyst
  • Odontogenic keratocyst
  • Lateral periodontal cyst and botryoid odontogenic cyst
  • Gingival cysts
  • Glandular odontogenic cyst
  • Calcifying odontogenic cyst
  • Orthokeratinized odontogenic cyst
  • Nasopalatine duct cyst

Malignant maxillofacial bone and cartilage tumours

  • Chondrosarcoma
  • Mesenchymal chondrosarcoma
  • Osteosarcoma

Benign maxillofacial bone and cartilage tumours

  • Chondroma
  • Osteoma
  • Melanotic neuroectodermal tumour of infancy
  • Chondroblastoma
  • Chondromyxoid fibroma
  • Osteoid osteoma
  • Osteoblastoma
  • Desmoplastic fibroma

Fibro-osseous and osteochondromatous lesions

  • Ossifying fibroma
  • Familial gigantiform cementoma
  • Fibrous dysplasia
  • Cemento-osseous dysplasia
  • Osteochondroma

Giant cell lesions and simple bone cyst

  • Central giant cell granuloma
  • Peripheral giant cell granuloma
  • Cherubism
  • Aneurysmal bone cyst
  • Simple bone cyst

Haematolymphoid tumours

  • Solitary plasmacytoma of bone

Tumours of the ear

Tumours of the external auditory canal

  • Squamous cell carcinoma
  • Ceruminous adenocarcinoma
  • Ceruminous adenoma

Tumours of the middle and inner ear

  • Squamous cell carcinoma
  • Aggressive papillary tumour
  • Endolymphatic sac tumour
  • Otosclerosis
  • Cholesteatoma
  • Vestibular schwannoma
  • Meningioma
  • Middle ear adenoma

Paraganglion tumours

  • Carotid body paraganglioma
  • Laryngeal paraganglioma
  • Middle ear paraganglioma
  • Vagal paraganglioma
Last update: 28 June 2017