self-concern vs egoism

self-concern and egoism both are nouns.

Word	Noun	Adjective	Verb	Adverb
self-concern	Yes	No	No	No
egoism	Yes	No	No	No

As nouns, self-concern and egoism are synonyms defined as:

Other synonyms of self-concern include egocentrism, self-centeredness, self-interest.

self-concern (noun)	egoism (noun)
concern for your own interests and welfare	concern for your own interests and welfare
	(ethics) the theory that the pursuit of your own welfare is the basis of morality