cancer vs sarcoma

cancer and sarcoma both are nouns.

Word	Noun	Adjective	Verb	Adverb
cancer	Yes	No	No	No
sarcoma	Yes	No	No	No

As nouns, sarcoma is a hyponym of cancer; that is, sarcoma is a word with a more specific, narrower meaning than cancer:

cancer: any malignant growth or tumor caused by abnormal and uncontrolled cell division; it may spread to other parts of the body through the lymphatic system or the blood stream
sarcoma: a usually malignant tumor arising from connective tissue (bone or muscle etc.); one of the four major types of cancer

Other hyponyms of cancer include lymphoma, carcinoma, cancer of the blood, leucaemia, leukaemia, leukemia.

cancer (noun)	sarcoma (noun)
any malignant growth or tumor caused by abnormal and uncontrolled cell division; it may spread to other parts of the body through the lymphatic system or the blood stream	a usually malignant tumor arising from connective tissue (bone or muscle etc.); one of the four major types of cancer