Table 1 The 12 major families of rare cancers developed by the Joint Action on Rare Cancers and the relevant tier-1 categories. Reproduced by Casali and Trama (2020) [5]

Head and neck tumours

• Epithelial tumours of the larynx

• Epithelial tumours of the hypopharynx

• Epithelial tumours of the nasal cavity and sinuses

• Epithelial tumours of the nasopharynx

• Epithelial tumours of major salivary glands and salivary gland type tumours

• Epithelial tumours of the oropharynx

• Epithelial tumours of the oral cavity and lip

• Epithelial tumours of the eye and adnexa

• Epithelial tumours of the middle ear

Digestive system tumours

• Epithelial tumours of the small intestine

• Epithelial tumours of the anal canal

• Epithelial tumours of the gallbladder and extrahepatic biliary duct

Thoracic tumours

• Epithelial tumours of the trachea

• Thymomas and thymic carcinomas

• Malignant mesothelioma

Female genital tumours

• Non- epithelial tumours of the ovary

• Epithelial tumours of the vulva and vagina

• Trophoblastic tumours of the placenta

Male genital and urogenital tumours

• Tumours of the testis and paratestis

• Epithelial tumours of penis

• Extragonadal germ cell tumours

• Epithelial tumours of renal pelvis, ureter, and urethra

Skin cancers and non-cutaneous melanoma

• Mucosal melanoma

• Uveal melanoma

• Adnexal skin carcinomas

• Kaposi sarcoma

Sarcomas

• Soft tissue sarcoma

• Bone sarcoma

• Gastrointestinal stromal tumours

Neuroendocrine tumours (NET)

• NET gastrointestinal pancreatic

• NET lung

• NET other sites

Endocrine organ tumours

• Thyroid cancers

• Parathyroid cancer

• Adrenal cortex cancer

• Pituitary gland cancer

Central nervous system (CNS) tumours

• Glial tumours and others

• Malignant meningioma

• Embryonal tumours of CNS

Paediatric tumours

• Hepatoblastoma

• Neuroblastoma and ganglioneuroblastoma

• Nephroblastoma

• Odontogenic malignant tumours

• Olfactory neuroblastoma

• Pancreatoblastoma

• Pleuropulmonary blastoma

• Retinoblastoma

Haematological tumours

• Lymphoid malignancies

• Myelodysplastic syndromes

• Myeloproliferative neoplasms (including mastocytosis)

• Myelodysplastic/myeloproliferative neoplasms

• Myeloid/ lymphoid neoplasms with eosinophilia and abnormalities of PDGFRA (platelet-derived growth factor receptor alpha), PDGFRB (platelet-derived growth factor receptor beta), or FGFR1 (fibroblast growth factor receptor 1), or with PCM1- JAK2

• Acute myeloid leukaemia and related neoplasms