Before Kenneth B. Schwartz died of terminal lung cancer in 1995, he founded the Kenneth B. Schwartz Center at Massachusetts General Hospital, a facility promoting compassionate treatment for patients in part patterned after the care given by his oncologist—Thomas J. Lynch, Jr.

Now Lynch, the chief of hematology and oncology at the Mass. General Cancer Center, will leave Harvard after 23 years to become the director of the Yale Cancer Center and physician-in-chief of the Smilow Cancer Hospital at Yale New Haven Hospital, Yale announced Wednesday.

“They gave me the opportunity to take some of the lessons I learned in the phenomenal success of MGH and apply it in a setting like Yale,” Lynch said. “It was an opportunity that was irresistible.”

He said that Yale is making a major investment in cancer research, both in clinical care and translational research, and that he has a once in a lifetime opportunity to lead it.

Those who worked with Lynch at Mass. General praised him for both his research and mentorship.

“Tom is a one in a million, a one in a billion leader,” said Jeffrey A. Engelman, a lung cancer specialist who trained under Lynch.

He said that Lynch is a visionary, both in his ability to develop young oncologists and in his research.

“This was his chance to build a cancer center from his own vision and he will be extraordinary.” Engleman said.

He said that Lynch, along with Cancer Center Director Daniel A. Haber, led what was probably the biggest discovery in lung cancer in the last 20 years. Lynch helped identify a new kind of mutation in the EGF receptor that has led to treatment for patients with this genetic mutation.

“Because of this work we now routinely do this genetic test on our patients, and if they have this mutation, they take a pill once a day and have a great chance of achieving remission,” Engleman said. “In lung cancer, remissions are normally hard to come by.”

In addition to his research and clinical work, Lynch founded Rounds, a program at the Schwartz Center that provides a monthly forum for hospital personnel to talk about their experiences during patient treatment. The program has spread to 165 sites around the nation and involves more than 37,000 doctors. Lynch still runs the sessions for over 125 people at Mass. General, according to Julie Rosen, the Schwartz Center’s executive director.

“He is a superb administrator and he is a superb human being,” Rosen said. “He is the doctor you want if you or your family member gets sick.”

—Staff writer Laura G. Mirviss can be reached at lmirviss@fas.harvard.edu.