It’s a pod-shaped machine that uses gamma radiation to target breast cancer tumors.
And it could make a big difference for women in treatment for early stage breast cancer.
The device also has the potential to shorten radiation treatment time and reduce harsh side effects.
Late last year, the GammaPod was cleared by the U.S. Food and Drug Administration (FDA) for use in patients with early stage breast cancer in conjunction with breast-conserving surgery.
The clearance was granted to Xcision Medical Systems, LLC.
Dr. Elizabeth M. Nichols is assistant professor of radiation oncology at the University of Maryland School of Medicine and clinical director of the Department of Radiation Oncology at the University of Maryland Medical Center.
Nichols is the principal investigator for the clinical feasibility study of the device.
She told Healthline that the University of Maryland Medical Center expects to be offering the treatment to patients by June 1.
UT Southwestern Medical Center in Dallas, Allegheny General Hospital in Pittsburg, and Ottawa Hospital in Ontario also anticipate introducing treatment with GammaPod within a year.
How GammaPod works
The patient lies on her stomach with her breast in a vacuum-assisted cup to prevent movement.
Rather than radiating the entire breast, GammaPod targets the tumor with focused beams of radiation from 36 rotating sources.
One treatment can take anywhere from 5 minutes to 40 minutes, depending on the specific treatment plan.
The GammaPod can send higher doses of radiation to the tumor than standard radiation.
Nichols said women involved in the study report that treatment hasn’t been painful or uncomfortable.
They also said they appreciated the fact that fewer sessions were necessary.
It’s for very specific patients
The GammaPod is not appropriate for every woman with breast cancer.
According to the FDA, GammaPod has not been shown to be as effective as whole-breast radiation therapy and is not intended to replace it.
“This would be considered a form of partial breast radiation, typically given for early-stage breast cancer, which would be stages 0, 1, and 2,” said Nichols. “It can be used on any type of breast cancer, even the rare subtypes. It’s dependent on stage.”
With regular radiation machines, a woman with early stage breast cancer might receive partial breast radiation twice a day for a week or two.
Nichols said the GammaPod can deliver treatment in just one to three sessions.
“It’s combining technology we use in other body sites such as brain, lung, and liver tumors. It’s taking stereotactic body radiation therapy and now being able to apply it to the breast,” she explained.
“The biggest point I try to make is that GammaPod is for select patients with early stage breast cancer. It’s not a technology that will apply to all women with breast cancer. Patients will be evaluated by a medical professional to figure out if they are a good candidate. We always want to do what’s best to cure the cancer. That’s our primary goal. If GammaPod is the right tool, that’s great. If not, there are other ways of delivering radiation,” said Nichols.
How it may improve breast cancer treatment
Nichols made it clear that GammaPod won’t affect whether a patient needs chemotherapy.
“Chemotherapy is independent of the need for radiation. Generally speaking, the patients who qualify for GammaPod would usually be women who do not need chemo. Most women who have a higher risk breast cancer will likely benefit from whole breast radiation,” she continued.
Dr. Wendy Woodward, professor and chief of the Clinical Breast Radiotherapy Service at The University of Texas MD Anderson Cancer Center, spoke to Healthline about radiation treatment.
“Radiation, to a certain degree, is an insurance policy for most patients. Most have already had surgery and/or chemotherapy and there’s a potential risk of [cancer] cells left behind. Radiation is an additional measure to ensure that cancer doesn’t come back,” she said.
“There’s an effort to make it more convenient. In some cases, it can be done in three or four weeks. There’s interest in doing it faster if you’re only treating the highest risk areas around the lumpectomy cavity. A lot of data suggests that for properly selected patients, it’s safe and effective to treat the tumor bed cavity and margin in a week,” said Woodward.
For women with more advanced breast cancer, partial breast radiation isn’t enough. Usually, these women have a mastectomy.
“There’s a risk of cells left behind in the chest wall or in unremoved lymph nodes. To help eliminate that risk, high-risk or lymph node-positive women are offered radiation to the whole chest wall and undissected lymph nodes,” said Woodward.
Radiation kills tumor cells by damaging their DNA. However, that radiation also has the power to damage healthy tissues near the tumor.
Woodward said the most common short-term side effects are skin redness and irritation and fatigue.
In the longer term, all tissues that are radiated can be affected. Tissues and muscles in the breast, shoulder, or back can feel tighter or firmer.
“The ribs are not at high risk, but you can have a rib fracture. The heart and lung can be affected if they’re in the treatment field, but we work hard to eliminate the heart from the field. You can have increased risk of heart disease 5 to 15 years later. There is a low chance of lung irritation. And it can increase the risk of arm swelling from treating lymph nodes,” explained Woodward.
By delivering radiation precisely where it’s needed, healthy tissue and organs such as the heart and lungs can be spared.
“What GammaPod is hoping to do is reduce the number of treatments. The burden of proof will be on those centers that have one to show this is feasible and is a good idea. How fast can you go? Will one treatment be more toxic or safe and easy? It’s not just can you — but should you. The long-term side effects remain to be seen with GammaPod,” said Woodward.
What women with breast cancer need to know
Woodward has some advice for women facing decisions about radiation for breast cancer.
“If radiation is recommended, what is the likelihood it will work and what is the expected toxicity? With whole breast radiation, we have decades of data on tens of thousands of women. If you’re interested in partial breast radiation and know it’s a reasonable option and recommended based on data, ask for details and data specific for that type of treatment,” she said.
“Some patients really enjoy being on the cutting edge of moving science forward. Some women prefer the tried and true. Just be sure to get the information you need to make a good decision for you. The FDA gives the green light to study and collect data. The outcome is not totally known yet,” said Woodward.
She noted that the clinical study involved only 17 patients.
Partial breast radiation and whole breast radiation are covered under most insurance policies. According to Nichols, radiation costs are typically billed by the number of treatments.
It’s too soon to know, but it’s possible that GammaPod could result in healthcare savings for insurance companies and across the board.
The future of GammaPod
Nichols believes it’s possible that there will eventually be a role for GammaPod in later stage breast cancer.
“There’s potential that GammaPod could be used for a boost treatment in cancer that has metastasized. In a more advanced setting, radiation therapy is given every day for four to five weeks in a row. Then five or six more treatments are focused on the surgery cavity at the end. GammaPod could be done in one treatment to replace that. But right now it’s only for early stage breast cancer,” she explained.
Nichols said that use of GammaPod for metastatic breast cancer is being explored in clinical trials.
“For some other cancers we combine radiation and immunotherapy and we can actually see all spots improve when done in combination. This hasn’t been done in breast cancer so much. We’re exploring giving treatment to the primary tumor in the breast and the potential for inducing an overall response. That’s a concept we’re looking at and hope to get funding for,” said Nichols.
Researchers in the United States and Europe are also looking at whether GammaPod can help some patients avoid surgery altogether.
“In clinical trial we’re hoping we’ll increase the number of women with no cancer left behind. We’re hoping to give radiation alone and follow the women long term,” she explained.
Nichols said there’s a whole portfolio of clinical trials opening in the near future, with a range of endpoints that include quality of life for breast cancer patients.