Radiation 'Boost' Can Prevent Breast Cancer Recurrence

Oct. 29, 2007— -- After battling breast cancer and being pronounced free of the illness, women are looking for anything that can help them stay healthy. Now it appears that an additional boost of radiation may help keep the disease at bay, according to a new study released Monday at the annual meeting of the American Society for Therapeutic Radiology and Oncology.

The study finds that women who receive the extra dose of radiation treatment are almost two times more likely to be cancer-free after 10 years than the women who had the traditional radiation therapy treatment.

Young women — below the age of 40 — showed more benefits after the extra treatment, but it helped all women to some degree.

"We are very pleased with these results. We see more than 80 percent of the patients still alive 10 years after treatment has ended," says study author Dr. Harry Bartelink, a radiation oncologist at the Netherlands Cancer Institute in Amsterdam. "In this study, we were able to analyze why the young patients were having this benefit. We are gaining more insight."

Previous research by the same group showed similar results, but this research was able to analyze how the benefits were greater for younger women.

Even though only 5 percent of breast cancer cases occur in women under 40, this group tends to have a higher rate of cancer recurrence, because they have many more years for the cancer to creep back.

"We are also finding ways to reduce the need for mastectomies, which leads to a better quality of life," says Bartelink.

Reconsidering the Rules of Radiation

Treating breast cancer in its early stages usually involves surgery to remove the tumor (lumpectomy), followed by radiation therapy to the breast over a six- to eight-week period to destroy any remaining cancerous cells.

"After lumpectomy, the whole breast is at risk of recurrence, but the area at greatest risk is the tumor bed," says Dr. Marisa Weiss, president and founder of breastcancer.org.

"Therefore, the dose of radiation required to eradicate cells in the tumor bed is greater than the dose required to treat the rest of the breast."

Radiation oncologists typically give the whole breast a smaller amount, and increase the dosage for the location of the tumor.

Doctors in this study — the largest ever to examine radiation treatments in women with breast cancer — gave one extra dose of radiation to this localized area where the lumpectomy was performed. The "boost" method became the standard of breast cancer care after the initial results with the same group of women were released five years ago, which was five years after their treatment ended.

"Since the overall [initial] study was 'positive' for adding the boost in the past, it has been the standard of care to do this for all women for several years now," says Dr. Harold Burstein, assistant professor of medicine at Harvard Medical School.

Bartelink says there is little risk to the added dose of radiation. "The one thing that can happen is that the amount of fibrosis [scar tissue] rises, from 1 to 4 percent. But this can be mediated through better surgical techniques."

Other doctors agree that the risks for the additional radiation are minimal. "This extra dose is not a high dose. So the extra side effects are marginal," says Weiss. She adds that patients can expect "just a little more transient swelling, tenderness and redness."

Personalized Breast Cancer Treatment Coming Soon

The researchers are looking to the future, for more ways to improve radiation therapy for women with breast cancer.

"We have just started another trial, with 1,800 women," says Bartelink. "Using tumor material we take from biopsies, we can predict which patients will need radiation, and how much they will need."

This type of personalized treatment for breast cancer may reduce the risk of breast cancer recurrence as well as reduce the need for mastectomies, according to Bartelink.

"Boosts do decrease the recurrences at the tumor bed," says Dr. Anne Rosenberg, a breast surgeon at Jefferson Medical College in Philadelphia. "This is especially important in young women, where their life expectancy is greater, and so the risk of recurrence in the future is greater."

Study author Bartelink is optimistic about future advances in radiation therapy.

"This is a major step forward, especially for the younger women," he says. "We are continuing to learn more."