PROTON NEWS

Nuclear physicist's work benefits breast cancer patients

Hampton researcher's work helps to fine-tune diagnoses and treatments

Cynthia Keppel
Cynthia Keppel, Ph.D is Scientific and Technical Director at the Hampton University Proton Therapy Institute in Hampton. (Adrin Snider, Daily Press / October 1, 2011)

By Prue Salasky, psalasky@dailypress.com | 757-247-4784
11:29 p.m. EDT, October 1, 2011

Cynthia Keppel talks at the speed of blur.

The race is on to bring proton therapy cancer treatment to the region.

The nuclear physicist, internationally known for her work with protons and neutrons, barely pauses to breathe when explaining her research and the different imaging techniques used to detect breast cancer.

A mammogram is a breast X-ray, in which the tumor, denser than healthy tissue, casts a detectable shadow, she says. It's highly sensitive but not specific enough to prevent unnecessary biopsies 60 percent of the time. Breast specific gamma imaging, on the other hand, radio-labels the tumors and maps their metabolic activity. When set over an X-ray, it gives physicians more specific information.


"It's good for those with scar tissue, denser breasts or implants. It's most important for younger women," says Keppel. For breast cancer patients, Keppel's research over the last decade has translated into technology allowing for more accurate and complete diagnoses and treatments.

And that is contributing to the vastly improved results for breast cancer patients. Once considered an automatic death sentence, breast cancer now has a 90 percent-plus, five-year survival rate for those diagnosed early.

Starting with imaging and diagnostics, Keppel's work has progressed to the use of proton therapy. She is now the scientific and technical director at the Hampton University Proton Therapy Institute, which opened last year. Since 2000 she has earned nine patents, including one to enhance functional breast imaging, and has several more pending. She is the recipient of Virginia's 2011 Outstanding Scientist award.

Keppel, 49, originally crossed disciplines to adapt her findings in nuclear physics at the Jefferson Lab to medical uses at the Center for Advanced Medical Integration, the state's first medical physics program that she founded at Hampton University. Her work there included helping to improve a therapy in which high-dose radiation is delivered internally to a lumpectomy site instead of by an external beam, thereby reducing treatment time to five days from 30 to 40. It also spares more healthy tissue.

"The treatment has very good outcomes and better cosmetic outcomes," she says, noting that it's particularly good for the elderly, the poor, or people in rural areas, who would otherwise have to get treatment every day for weeks.

For her, one discovery has led to another — and another. Increasingly, her focus is on protecting healthy tissue and limiting damage from cancer treatments.

More accurate diagnosis through breast specific gamma imaging, or BSGI, helps to achieve this. The Dilon 6800 gamma ray camera used for this is licensed to Dillon Technologies in Newport News. Clinical scientist Doug Kieper, a company vice president, worked with Keppel on a series of her patents. He describes his specialty as being an interpreter between disciplines, "helping physicians and physicists to understand the language they're both speaking in order to develop devices that meet the needs of patients."

There are two main uses for gamma imaging: after a difficult-to-read mammogram and in planning treatment for people with a known cancer, Kieper says. In the first instance, it detects cancers in almost 10 percent of those tested — as compared to mammograms, which find two cancers per 1,000 screenings — and in the latter it finds additional cancers in between 10 and 14 percent of patients, vital information for surgeons.

Both Riverside and Sentara health systems were quick to adopt the technology in 2007, soon after it became available. While mammography remains "the gold standard" for basic screening, according to Kelley Allison, medical director of Sentara's Dorothy G. Hoefer Breast Center in Newport News, she praises the gamma imaging as an excellent adjunct diagnostic tool.

One of its uses at the center is to shrink a tumor before surgery in patients who are undergoing chemotherapy.

"The trend I'm seeing is that it's a very good test for this," Allison says.

At Peninsula Radiological Associates, which contracts with Riverside, radiologist Curtis Stoldt also uses the molecular imaging process as an enhancement.

"It's less expensive than an MRI," he says. "They are very different technologies, however the indications for doing both procedures are the same."

As a leading force at the Proton Therapy Institute, Keppel continues to focus on sparing healthy tissue. The institute's cancer treatments involve using a proton beam to target and kill cancer cells with sub-millimeter precision.

"When I started work on the institute, she was the first person I put on my team. She has worked wonderfully. I'm proud of her," says HU President William Harvey, who originally hired Keppel out of graduate school as a physics professor 16 years ago.

"It's a wonderful, exciting thing," says Keppel. "It can treat any local tumor. It's so precise. We can drive the radiation just into the tumor."

The center focuses mainly on prostate, head and neck, and pediatric cancers with breast cancer patients currently making up a small minority.

"There's nothing in our head, neck, brain that won't impact our life," she says. "The breast is mostly fat. It's not the same thing as a child's brain." She adds, though, that for some breast tumors the heart or lungs may be involved and proton therapy can reduce the harmful side effects.

For Mary Grace Blair, who completed 33 treatments last month for a recurrence of breast cancer, it was the only radiation option because of a chronic lung disease.

"I have pulmonary fibrosis. We're trying to preserve the lungs," she said in a phone interview from her home in Pennsylvania. "There was no pain. I was in and out within 30 minutes every day. I felt confident it would work without damaging other organs."

The precision involved with proton therapy makes the smallest movement critical and patients must be completely immobilized. Breathing causes breast cancers (and others) to move during treatment, so Keppel has now turned her attention to "respiration motion management" or how best to deliver pinpoint treatment in those cases. To test her team's theories, a high-tech Norfolk company, CIRS, supplies "phantoms" that can mimic any human tissue.

Keppel expects to have the problem solved within a year.

"The next step will be to actually chase the tumor around with the beam," she says.

 

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