Rancho Santa Fe doctor helping bring cancer treatment to ‘next level’ at Scripps Proton Therapy Center


By Joe Tash

Dr. Huan Giap’s path from his native Vietnam to his current job of treating cancer patients with radiation therapy in San Diego took many twists and turns.

As a teenager, Giap was among a group of Vietnamese “boat people” who landed in Thailand, where he spent a year in a refugee camp. Inspired by an American priest he met at the camp, Giap emigrated to the U.S. at age 18, intending to study for the priesthood, but instead earning a master’s degree in nuclear engineering at Texas A&M University.

Giap then decided to go back to school, earning both a medical degree and a doctorate in a special joint program at the University of Texas Health Science Center.

At 50, the Rancho Santa Fe resident is about to embark on the next chapter of his career, as a member of the medical staff of a new proton therapy center under construction in the Carroll Canyon area of Mira Mesa, which will be operated by Scripps Health. Giap joins the center as chief of breast, gastrointestinal and lung proton beam therapy.

The $220 million center is slated to open at the end of this summer, following three years of construction. When completed, the facility will have the capacity to treat 2,400 patients per year.

While he has enjoyed all of his various endeavors over the past three decades, which have included working in a nuclear power plant and serving as chief medical officer for the company that is building the new Scripps proton therapy center, Giap said his true passion is treating patients.

“At heart I’m a clinician, I’m a doctor. That job gives me the most satisfaction,” Giap said.

Giap worked as a radiation oncologist at Scripps Clinic in La Jolla from 1998 to 2008, and served his residency at Loma Linda University Medical Center.

Throughout his career, he has used both traditional X-ray radiation, as well as proton radiation, to treat patients with different forms of cancer.

The major advantage of proton therapy, said Giap and Dr. Carl Rossi, medical director of the new proton therapy center, is that it can target tumors more precisely than traditional X-ray radiation, thus having less impact on surrounding healthy tissue and organs, and causing fewer side effects for patients.

At the heart of the technology is a device called a cyclotron, which is just six feet wide and nine feet tall, but weighs 90 tons. Rossi said the machine is basically a large electro-magnet made of steel, which accelerates the protons to great speeds.

The protons are then directed to the center’s five treatment rooms, where they are focused on the patients’ tumors.

Unlike X-rays, which travel through the body, protons can be directed to stop at very precise points, with accuracy to within two to three millimeters. For example, he said, when proton therapy is used to treat breast cancer, it can stop at the chest wall, and avoid hitting the heart. A recent study found that women treated for breast cancer with X-ray radiation have a higher risk of developing heart disease later in life, because the heart is often exposed to radiation.

Reducing both the short- and long-term side effects of cancer treatment is becoming more important as medical science advances, resulting in more people being cured and living for longer periods after treatment, Rossi said. That is especially true for children, who have a longer life expectancy and are also more susceptible to the harmful side effects of treatment.

With proton therapy, Rossi said, “We treat substantially less good stuff (healthy tissue) to treat the bad stuff (cancer).”

The idea of using proton therapy actually dates back to the 1940s, and initially, very small numbers of patients were treated in physics labs. Today, there are about 12 operating proton therapy facilities in the U.S., with about six more under construction, Rossi said. The new Scripps center will be the second in California and the third west of the Rockies.

In the past, proton therapy has been used for pediatric cancer, as well as prostate and lung cancer and brain tumors, Giap said. It’s increasingly being used for breast cancer, and tumors of the gastrointestinal tract, he said. Proton therapy is most beneficial for localized tumors, as opposed to cancers that are widespread in the body.

“Proton therapy is a piece of the puzzle, bringing cancer treatment to the next level,” he said.

“It’s exciting for San Diego County. I’m so happy to be a part of it,” Giap said.

Giap and his wife, Anna, moved to Rancho Santa Fe about 10 years ago. Their two children, Fantine, 20, and Bosco, 19, attended R. Roger Rowe School. Both are now in college, and plan to follow their father into the field of radiation oncology, Giap said.

Rossi, who worked with Giap at Loma Linda, said the new center is fortunate to have doctors such as Giap on staff.

“He was the most brilliant person we had come through in the 20 years I was at Loma Linda,” Rossi said of his colleague.

Fast Facts


Huan B. Giap, M.D., Ph. D.


Chief of breast, gastrointestinal and lung proton beam therapy at the new Scripps Proton Therapy Center, now under construction in Mira Mesa.


Medical degree, University of Texas Health Science Center; doctorate, medical physics, University of Texas Graduate School of Biomedical Science; bachelor’s and master’s degrees in nuclear engineering, Texas A&M University.


Wife, Anna; daughter, Fantine, 20, and son, Bosco, 19


Rancho Santa Fe

Current Book:

“Cha: A biography of Father ‘Joe’ Devlin, SJ,” by Raymond Devlin

Favorite movie/book/musical:

“Les Misérables”


“Your time is limited, so don’t waste it living someone else’s life. Don’t be trapped by dogma — which is living with the results of other people’s thinking. Don’t let the noise of others’ opinions drown out your own inner voice. And most important, have the courage to follow your heart and intuition. They somehow already know what you truly want to become. Everything else is secondary.” — Steve Jobs