@quimbie

From Google: "McQueen underwent a controversial program developed by William Donald Kelley, a former orthodontist who had his license revoked in 1976."

https://www.mesothelioma.com/blog/steve-mcqueen-and-mesothelioma-an-actor-and-veterans-last-battle/ -- Quotes:

"Many scientists regarded Dr. Kelly’s methods as quackery. Dr. Kelly’s spin on Gerson Therapy was based on the belief that all cancers stem from a lack of a pancreatic enzyme. This method of treatment centered around unorthodox methods, including: ...

"The treatment also included a daily dose of laetrile, a cancer drug created from the pits of apricots. The drug was never approved by the U.S. Food & Drug Administration (FDA). The National Cancer Institute (NCI) described its use as ineffective and dangerous. In later studies, it was shown this type of therapy actually worsened the patient’s quality of life. As McQueen sought out this controversial treatment in Mexico, ...

"McQueen’s supposed recovery was short-lived. Although his American doctors previously warned McQueen that his heart wasn’t strong enough for surgery, his new doctors operated anyway. The surgery itself went smoothly. The doctors removed some tumors from his neck. But, McQueen died from cardiac arrest the next day. He was 50 years old."

To quote a very old saying, "The patient died, but the operation was a success."