Can You Pause Radiation for Triple-Negative Breast Cancer? A Study Says No
Interrupting radiation therapy treatment after surgery for triple-negative breast cancer for two or more days led to worse overall survival, according to a study.
The research was published online on July 3, 2023, by the Journal of the National Cancer Institute. Read the abstract of “Effect of Treatment Interruptions on Overall Survival in Patients with Triple Negative Breast Cancer.”
Triple-negative breast cancer is invasive breast cancer that is:
estrogen receptor-negative
progesterone receptor-negative
HER2-negative
The cells in triple-negative breast cancer don’t have receptors for the hormones estrogen or progesterone and don’t make too much of the HER2 protein. So triple-negative breast cancers don’t respond to hormonal therapy medicines or the medicines that target the HER2 protein.
Early-stage, triple-negative breast cancer is often treated with radiation and chemotherapy after surgery.
Overall survival is how long people live, whether or not the cancer comes back or grows.
Radiation therapy schedules
A traditional external whole-breast radiation schedule includes about 25 treatments — one treatment five days a week for five to seven weeks.
Because a five- to seven-week nearly daily commitment is difficult for many people, doctors developed a radiation therapy schedule that involves fewer treatments delivering higher doses of radiation during each treatment. This shorter schedule — called an accelerated or a hypofractionated schedule — allows people to receive about the same radiation dose in a three- to five-week schedule.
But a hypofractionated scheduled still means a near daily commitment for three to five weeks. It can be difficult to schedule vacations or other travel if you’re receiving radiation therapy. In other cases, doctors may recommend taking time off from radiation therapy to allow skin to heal.
Studies looking at radiation for lung and prostate cancer found that people who had very few or no interrupted treatment days had better overall survival than people who had more interrupted treatment days.
In this study, the researchers wanted to see if taking a break from radiation therapy for early-stage and locally advanced triple-negative breast cancer affected outcomes.
Locally advanced breast cancer is breast cancer that has spread to tissue near the breast, but not to parts of the body away from the breast.
About the study
The researchers analyzed the records of 35,845 women who received treatment for early-stage or locally advanced triple-negative breast cancer between 2010 and 2014. All the information came from the National Cancer Database. The National Cancer Database includes information collected from more than 1,500 Commission on Cancer-accredited facilities. It is overseen by the American College of Surgeons.
Half the women were older than 58 years and half were younger; 74% of the women were white. About 56% of the women in the study had private health insurance. Nearly 60% of the women had lumpectomy and about 40% had mastectomy.
Women who had more than 15 interrupted treatment days were excluded from the study.
The researchers defined the number of interrupted treatment days as the difference between the total number of days from the start to the end of radiation treatment, including both initial treatment and boost treatment, if appropriate, and the total number of expected treatment days. The researchers added two weekend days for every five treatment days because they assumed that radiation therapy was only given on week days.
Overall:
14,625 women had zero to one interrupted treatment days
14,292 women had two to five interrupted treatment days
4,962 women had six to 10 interrupted treatment days
1,966 women had 11 to 15 interrupted treatment days
The researchers’ analysis showed that more interrupted treatment days were linked to worse overall survival.
Compared with women with zero to one interrupted treatment days, women with:
two to five interrupted treatment days were 6.9% more likely to die
six to 10 interrupted treatment days were 24% more likely to die
11 to 15 interrupted treatment days were 27% more likely to die
“To our knowledge, this is the first study reporting on the association between treatment interruptions during radiation therapy and overall survival in the setting of patients with non-metastatic triple-negative breast cancer,” the researchers wrote. “Patients with a greater number of interrupted treatment days experienced progressively worse [overall survival].”
What this means for you
According to Marisa Weiss, MD, Breastcancer.org founder and chief medical officer, who is also a radiation oncologist, care without delays is extremely important, especially for women diagnosed with triple-negative breast cancer.
“Still, it’s not just as simple as length of time under treatment and missed days,” she explained. “We need to understand what is going on that’s causing these delays. It probably has to do with other factors that also can affect outcomes, such as other health conditions a person might have, including side effects from treatment.”
Dr. Weiss went on to explain that other barriers related to social determinants of health likely play a role, including:
access to health insurance
job inflexibility related to getting care
not having a job and the benefits that come with a job
transportation, nutrition, child care, and elder care problems
housing security
Dr. Weiss emphasized that the message is to avoid delays and interruptions in treatment.
It makes sense to talk to your doctor about how to manage any skin side effects you may have before you start radiation therapy. This way, you can start managing side effects before they become severe and avoid pausing treatment.
If you think that you might have problems making it to radiation therapy appointments, ask your doctor about a shorter, hypofractionated radiation schedule.
"Radiation needs to start in a timely manner,” Dr. Weiss added. “Then once you start your treatment course, it needs to continue without interruptions.”
— Last updated on December 4, 2023 at 4:40 PM