egocentric vs self-serving

egocentric is a noun but self-serving is not a noun.

Word	Noun	Adjective	Verb	Adverb
egocentric	Yes	Yes	No	No
self-serving	No	Yes	No	No

As adjectives, egocentric and self-serving are synonyms defined as:

egocentric and self-serving: concerned chiefly or only with yourself and your advantage to the exclusion of others

Other synonyms of egocentric include egoistic, egoistical, self-centered, self-centred, self-seeking, selfish.

egocentric (noun)	self-serving (noun)
a self-centered person with little regard for others

egocentric (adjective)	self-serving (adjective)
concerned chiefly or only with yourself and your advantage to the exclusion of others	concerned chiefly or only with yourself and your advantage to the exclusion of others