The doctor chose a life of self-abnegation providing medical care for the poor around the world.
Self abnegation is a person putting their needs and wants aside for the sake of others.
An example of self abnegation is a mother giving the last of the food in the house to her hungry child.
lack of consideration for oneself or one's own interest; self-denial
The setting aside of self-interest for the sake of others or for a belief or principle.