egocentrism vs self-interest

egocentrism and self-interest both are nouns.

Word	Noun	Adjective	Verb	Adverb
egocentrism	Yes	No	No	No
self-interest	Yes	No	No	No

As nouns, egocentrism and self-interest are synonyms defined as:

egocentrism and self-interest: concern for your own interests and welfare

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

egocentrism (noun)	self-interest (noun)
concern for your own interests and welfare	concern for your own interests and welfare
	taking advantage of opportunities without regard for the consequences for others