George Hahn, radiation biologist who pioneered heat treatment for cancer, dies at 98

A personal tragedy spurred Hahn, who had escaped Nazi Europe as a child, to pursue a career seeking new therapies for cancer.

- By John Sanford

George Hahn

George Hahn, PhD, a professor emeritus of radiation oncology at Stanford Medicine who pioneered the use of heat to help treat cancer, died March 10 at his home in Carmel Highlands, California. He was 98.

“Dr. Hahn put his heart into his work, always thinking of the patients who could one day benefit from his research advances,” said Lloyd Minor, MD, dean of the Stanford School of Medicine and vice president of medical affairs at Stanford University. “We should all aspire to the humanity and selflessness he demonstrated as a scientist and mentor. We will miss him tremendously.”

Hahn arrived at a career in biomedical science by way of personal tragedy. His second-eldest son, David, was 10 years old when he was diagnosed, in 1961, with non-Hodgkin lymphoma. David was treated at Stanford Hospital under the care of Malcolm Bagshaw, MD, a leading radiation therapist who later served as Stanford Medicine’s founding chair of the Department of Radiation Oncology. At the time, however, chemotherapy agents to treat the disease didn’t exist. David died about a year later.

David’s death spurred Hahn to devote his career to cancer research. He was in his late 30s when he enrolled in the biophysics PhD program at Stanford Medicine, having already earned a master’s degree in physics at the University of California, Berkeley, nearly a decade earlier. Even before matriculating, he began working in Bagshaw’s lab.

“One of the most remarkable things about my father is what he did with his grief,” said Hahn’s daughter, Nina Hahn, a veterinarian living in Carmel Valley, California. “He turned it into research.”

In a handwritten letter to Hahn in 1993, Bagshaw wrote, “There is no doubt that our first meeting was most crucial when we planned strategy to try to arrest David’s relentlessly progressive neoplasm. Perhaps I should not recall that sadness in this letter but that is a part of our lives and I think of it.”

Hahn earned his PhD in 1966 and was hired the same year as an assistant professor of radiology. He went on to a distinguished career as a researcher and mentor.

“George became a well-respected leader in radiation biology,” said Sarah Donaldson, MD, professor emerita of radiation oncology.

Escape from Nazi Europe

George Max Hahn was born Jan. 30, 1926, in Vienna to Jewish parents. After Anschluss — the incorporation of Austria into the German Reich — in 1938, Hahn went to the Netherlands through Kindertransport, the organized project to move Jewish children out of Nazi-controlled territory. (His older sister was taken to England.)

He lived in an orphanage in Holland until his parents managed to secure visas to the United States. They settled in Sacramento, California, where Hahn attended C.K. McClatchy High School. He enlisted in the Army toward the end of World War II. Because he was fluent in German, he was transferred to the Counter Intelligence Corps, where he assisted with the arrest and interrogation of Gestapo and Waffen-SS personnel.

Returning to California after the war, he enrolled at UC Berkeley with funding from the G.I. Bill, earning a bachelor’s degree in 1952 and master’s degree in 1955 in physics. As an undergraduate student, he married Joyce Webb, whom he had known in high school.

George Hahn and his wife, Joyce, bought a second home in Guatemala after retiring.
Courtesy of the Hahn family

He worked at Firestone Tire and Rubber Co., which at the time had a defense contract to develop a guided missile, before joining, in 1957, the faculty of the Naval Postgraduate School in Monterey, where he taught electronics. After the death of his son in 1962, he left the job to begin graduate studies focused on cancer research at Stanford Medicine.

Research and mentorship

Hahn co-authored some 200 scientific papers. He conducted groundbreaking research on the use of hyperthermia — the heat treatment of cancer cells — to make tumors more vulnerable to radiation and chemotherapy. With funding from the National Cancer Institute, he led a multiyear investigation into how heat and ultrasound influenced drug responses in cancer.

Hahn was a founding member of the Hyperthermia Society and served as president of the Radiation Research Society from 1998 to 1999.

Today, Hahn’s discoveries are reflected in the hyperthermic treatments of certain sarcomas, melanomas and abdominal cancers, said George A. Fisher, MD, PhD, professor of oncology and the Colleen Haas Chair in the School of Medicine.

And while high-energy, focused heat ablation is more often used to treat cancers today than the relatively low-temperature application of heat Hahn was studying, his work helped pave the way to new therapies, Fisher said.

“The idea of heating tumors led to high-microwave ablation, radiofrequency ablation and different ways of applying heat to deeper tumors,” Fisher said. “We use those treatments routinely now for metastasis in the liver, for instance. But we do them at very high temperatures, whereas George’s expertise was in the use of more moderate temperatures and how it affected tumor cells.”

There are many personal stories of how George Hahn impacted the lives of young people, gave them an opportunity, gave them some guidance and helped them.

Hahn was known as a generous and supportive mentor to students and trainees. When Fisher was in his early 20s and, with no research experience, trying in vain to get a job at Stanford Medicine, Hahn allowed him to volunteer in his lab. There, Fisher received training in research techniques and eventually landed a paid job as a lab technician. Hahn and one of his colleagues then nominated Fisher to be a doctoral student in the cancer biology program, which was new at the time. Hahn served as Fisher’s PhD adviser.

“There are many personal stories of how George Hahn impacted the lives of young people, gave them an opportunity, gave them some guidance and helped them,” said Donaldson, who, as a resident at the Stanford School of Medicine from 1969 to 1972, worked in Hahn’s lab.

“He was a very distinguished faculty member but very approachable, and he always made time for students and trainees,” she said. “He didn’t assert himself with grandiosity. He was rather humble.”

Fisher recalled that when a supermarket tabloid exaggerated some of Hahn’s findings, writing that hyperthermia was going to cure cancer, Hahn was flooded with letters from cancer patients worldwide asking him for access to the treatment.

“For several weeks straight, George was still in his office after I would leave the laboratory at 6 or 7 p.m.,” Fisher said. “And what he was doing was personally writing to every person who wrote him asking for that treatment to say how sorry he was that it was not ready for prime time, and how he hoped that their loved ones would do OK with standard treatments. That’s the kind of guy he was.”

Falling for Central America

After retiring from Stanford Medicine in 1993, Hahn and his wife, Joyce, traveled extensively. Earlier, they had visited Central America and fallen in love with the region, Nina Hahn said. They bought a house in Panajachel, Guatemala, around 1990, and both became deeply interested in Mayan culture and art. Hahn also wrote several books, including a memoir titled The Lottery and a fictionalized biography of Alan Turing, the mathematician and computer scientist.

Joyce died in 2016. In addition to his daughter, Nina, Hahn is survived by two sons, Peter Hahn of Saranac Lake, New York, and Jack Hahn of San Francisco; four grandchildren; and seven great-grandchildren.

In lieu of flowers, donations may be made to the Guatemala Friends Scholarship Program.

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