Cancer vs doer

Cancer and doer both are nouns.

Word	Noun	Adjective	Verb	Adverb
Cancer	Yes	No	No	No
doer	Yes	No	No	No

As nouns, doer is a hypernym of Cancer; that is, doer is a word with a broader meaning than Cancer:

Other hypernyms of Cancer include actor, worker.

Cancer (noun)	doer (noun)
type genus of the family Cancridae	a person who acts and gets things done
the fourth sign of the zodiac; the sun is in this sign from about June 21 to July 22
a small zodiacal constellation in the Northern Hemisphere; between Leo and Gemini
(astrology) a person who is born while the sun is in Cancer