Family and friends are devastated by the death of Paul Kalanithi.
Kalanithi made a video for Stanford about being a surgeon-turned-patient.
He was diagnosed with stage four lung cancer in 2013. He wrote about it in an op-ed in the New York Times titled "How Long Have I Got Left".
"Medical training is very future-oriented. You're always thinking about five years down the line. I don't know what' I'll be doing. I may be dead, I may not be. And, so it is not all that useful to spend a lot of time thinking about the future, beyond lunch," Kalanithi said in the video.
In his parting words to his daughter Cady, he says she has given him "a joy unknown to me in all my prior years. In this time, right now, that is an enormous thing."
Kalanithi was 37 years old.
He and his wife, Dr. Lucy Kalanathi, supported the Bonnie J. Addario Lung Cancer Foundation, to raise money for research and treatment.
Kalanithi's brother, Suman Kalanithi, wrote in an email Tuesday that Paul died peacefully and on his own terms, surrounded by family. He is survived by his wife and daughter, parents, and two brothers.
The family is working on memorial arrangements, according to Stanford Medicine.
Donations can be made to the Dr. Paul Kalanithi Memorial Fund at Stanford or to the Lung Cancer Foundation.
Bay City News contributed to this report.