Radiation of Just Part of the Breast Can Stop Cancer's Return
A long-term study comparing two types of radiation treatment for early breast cancer found that accelerated partial breast radiation (APBI) appeared to do as well as standard whole breast radiation for keeping cancer at bay.
The study looked at 10-year recurrence rates. The findings mean the partial breast procedure may offer women another choice for treating early-stage breast cancer.
"APBI is a safe and less invasive treatment as compared to whole breast irradiation," said the study's lead author, Dr. Icro Meattini, an associate professor at the University of Florence in Italy. "It is cost-effective and the overall treatment time is diminished."
He said a full course of APBI treatment requires 10 days. In comparison, whole breast radiation requires at least three to four weeks, but typically takes about six weeks.
In early breast cancer, radiation therapy may be used after surgery (commonly called lumpectomy) that removes only the tumor and some surrounding tissue. When a tumor is removed, however, there's always a concern that cancer cells might be left behind. Radiation therapy can destroy any remaining cancer cells, according to the American Cancer Society (ACS).
Just as it sounds, whole breast radiation exposes the entire breast to radiation and can take up to seven weeks, the ACS says. If a higher dose of radiation is used, the course of treatment is considerably shorter.
Accelerated partial breast radiation relies on a higher dose of radiation that is concentrated on only part of the affected breast, according to the ACS.
The current study included 520 women with stage 1 or stage 2 breast cancer. Most had hormone-receptor positive, HER-2 negative breast cancer. All were over 40 and most were over 50. Participants were randomly assigned to receive either whole or partial breast radiation.
Their five-year follow-up found no significant difference in survival rates or tumor recurrence.
At 10 years, 3.3% of those given partial breast radiation and 2.6% of those who had whole breast radiation experienced a recurrence of breast cancer. Researchers said this difference wasn't statistically significant.
Breast cancer specific survival at 10 years was also similar: 97.6% for women who had partial breast radiation and 97.5% for those who had whole breast radiation.
As debate about the right course of treatment continues, Meattini said that in well-selected patients, APBI should be considered an option.
He noted that partial breast treatment had better outcomes for skin problems due to radiation and for breast appearance, as rated by both doctors and patients.
The findings were scheduled to be presented Thursday at the San Antonio Breast Cancer Symposium. Findings presented at meetings are typically viewed as preliminary until they've been published in a peer-reviewed journal.
Dr. Stephanie Bernik, chief of breast service at Mount Sinai West in New York City, called the study "exciting news" for patients with early stage breast cancer. She wasn't involved with the research.
"This study showed that the 10-year rates of recurrence were similar to the five-year rates, and adds to the growing body of research that suggests more is not always better," Bernik said.
Because APBI cuts the time needed to complete a full course of treatment, Bernik said it makes radiation therapy an option for more women.
Accelerated partial breast radiation "will open the door to this modality to women that previously opted for mastectomies due to inability to get to a radiation facility," she said. "Many women do not live close to a treatment center, but might now consider spending a week away from home compared to over a month."
The shorter treatment time also allows patients to get back to work and family faster, Bernik noted.
But, she added, larger studies may be needed to confirm the findings and ensure overall safety.
Learn more about breast cancer radiation options from the American Cancer Society.
SOURCES: Icro Meattini, M.D., associate professor, radiation oncology, University of Florence, and clinical oncologist, Florence University Hospital, Italy; Stephanie Bernik, M.D., chief, breast service, Mount Sinai West, New York City, and associate professor of surgery, Ichan School of Medicine at Mount Sinai; presentation, San Antonio Breast Cancer Symposium, San Antonio, Texas, Dec. 12, 2019