Davis Jr. who was married to Altovise Davis (now deceased) and had four childrengrew up in Harlem, New York to Vaudeville performer parents and was a member of the “Rat Pack” along with fellow late legends Frank Sinatra, Dean Martin, Peter Lawford (a socialite and brother-in-law to president John F. Kennedy), and variety show host Joey Bishop. They were a close group of friends who often performed together in Vegas casinos and were known for their decadent partying as much as their talent. Davis Jr. lost his right eye in a automobile accident on November 19, 1954, in San Bernardino, California.

As a man who experienced brutal racism ever since going into the army at 18, Davis used his talent to try to gain acceptance. He was known for being one of the first Black entertainers to break through barriers in the mainstream media.”I know the feeling of frustration which surges inside when only color stands between you and the proper respect for human dignity, equal opportunity and, above all, the chance to be treated like a man,” he wrote in 1967. “Slums, lack of quality education, denial of equal job opportunities and so little change to overcome the effects of second-class citizenship.” He asked the entertainment industry “to help eliminate the problems which have created bitterness and despair among so many.”

A Throat Cancer Diagnosis

Known for smoking heavily, Davis Jr. was first diagnosed with throat cancer in September 1989.  One of his doctors at the time, said that he was expected to make a full recovery after undergoing chemotherapy and radiation treatment.

‘”I’ll take the prescribed treatment and, with the help of the good Lord, will be back cooking (performing) by the end of the year,” Davis had said in a statement.

Davis Jr. was back in the hospital a few months later for a gum infection that wound up being a recurrence, and doctors found an even larger sore that was reportedly “inoperable.”

His good pal Frank Sinatra, and countless others, stopped by his home in the weeks before he lost his fight.

Advancements in Therapy for Head and Neck Cancers

In recent years, proton therapy has been used as an alternative to standard radiation, particularly in more sensitive areas like head and neck cancers and lung cancer. (Protons are positively charged particles found in the nucleus of atoms.)

Unlike x-rays, protons are very heavy, and they lose speed quickly. Physicians can better control where the proton releases most of its energy so that the radiation stops at the target, resulting in fewer side effects compared to radiation. Essentially, it spares surrounding tissue. Davis Jr. had problems speaking after treatment for throat cancer.

Related: Proton Therapy: When Is Expensive Cancer Treatment Really Worth it?

The American Cancer Society says that proton therapy, which is often more expensive than standard radiation, delivers “60% less radiation to healthy tissue around the tumor.”

“Traditional x-ray therapy and the newer proton therapy are both types of radiation,” Dr. Keith Cengel from the University of Pennsylvania tells SurvivorNet. They destroy cancer cells by damaging their DNA, or genetic make-up. “X-rays are kind of like a bullet. As they pass through a person, they cause the most damage right under the skin. They keep on passing through your tissues and eventually exit the body. That’s why they can often damage healthy cells along with the cancer cells.