Self-serving and Self-interest

Self-serving adjective - Overly concerned with one's own desires, needs, or interests.

Self-interest and self-serving are semantically related In some cases you can use "Self-interest" instead a noun phrase "Self-serving".

Self-interest noun - Excessive interest in oneself.

Self-serving and self-interest are semantically related in self-seeking topic. Sometimes you can use "Self-serving" instead a noun phrase "Self-interest".