Ewing's tumour vs British spelling

Ewing's tumour and British spelling both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ewing's tumour	Yes	No	No	No
British spelling	Yes	No	No	No

Ewing's tumour (noun)	British spelling (noun)
malignant tumor in bone marrow (usually in the pelvis or in long bones)	English orthography used in the UK, Ireland and most of the Commonwealth (characterized by 'analyse', 'centre' and 'useable')