What did Augustus have in the fault in our stars?

Furthermore, what does Augustus die from in the fault in our stars?

So yeah Augustus died due to cancer which stopped his heart but at times i wonder that wouldn't the story be more beautiful if he had lived and be with Hazel, for Hazel. So Augustus has struggled with osteosarcoma cancer in his right leg and when he got a artificial leg he was cleared from his cancer.

Thereof, why did Augustus Waters die?

Because July 2 is the day Augustus Waters, played by Ansel Elgort (above left), died of cancer.

I feel so fortunate that an intellectual giant like yourself would deign to operate on me.” “Augustus, perhaps you'd like to share your fears with the group.” “I fear oblivion,” he said without a moment's pause. “I fear it like the proverbial blind man who's afraid of the dark.”