Intraoperative Radiation Therapy—Convenience and Excellent Outcomes for Breast Cancer Patients
Fellowship-trained breast surgical oncologist Veronica Shim MD, specializes in personalized breast cancer treatment and hereditary women's cancer risk management at Kaiser Permanente’s Oakland Medical Center.
“For many of our patients, breast cancer is a chronic disease—the time between diagnosis and survivorship can be a long journey,” says Dr. Shim. “As a breast surgical oncologist, I work with a team of breast care experts to assist my patients in developing a treatment plan that reflects the patient’s personal values.”
KP Oakland Medical Center offers Intraoperative Radiation Therapy (IRT) to a selected group of early breast cancer patients to provide more convenient option to the traditional radiation method.
What is a breast surgical oncologist?
A breast surgical oncologist specializes in the surgical management of breast cancer from risk reduction to survivorship. At Kaiser Permanente, a breast surgical oncologist works with a team of breast cancer specialists in providing each patient with an expertise-driven coordinated care plan. All of our breast cancer patients, once diagnosed, are evaluated with an interdisciplinary team of specialists, all of whom work primarily on breast cancer. That way a second opinion is built-in to the treatment recommendation.
What is Intraoperative Radiation Therapy (IRT)?
IRT delivers a highly targeted, concentrated dose of radiation directly to the tumor bed during surgery, immediately after the tumor has been removed—unlike traditional radiation therapy in which patients receive multiple, daily treatments after surgery for up to six weeks.
After the tumor has been located and removed, a radiation tool is inserted into the breast cavity via balloon catheter to administer a targeted dose to the site. IRT takes 15-30 minutes.
What are the benefits of IRT?
Most local recurrence occurs in the original tumor bed. IRT helps destroy the microscopic tumor cells that may be left behind after tumor removal. Unlike whole breast external beam radiation therapy, IRT is highly targeted, allowing us to spare more of the healthy tissue, and shield other vital organs from radiation exposure, particularly the heart, lungs, and glands. Women who opt for IRT therapy suffer from fewer skin side effects.
IRT is also far more convenient for our patients. It’s one treatment administered during surgery, versus multiple treatments. External beam radiation requires daily trips to a medical facility for up to six weeks. IRT is administered once, immediately after excision of the tumor during surgery.
Are there downsides to IRT?
IRT has a 5-year follow up data compared to whole breast radiation that has a 20 year follow up data. We only offer IRT to a selected group of women who fit the eligibility criteria, and a close follow up is needed to validate the outcomes. We have set up a database so that we can monitor the outcomes of the IRT treatment among our patients.
Who is a candidate for IRT?
At the Oakland Medical Center, we offer IRT to postmenopausal woman with a new diagnosis of early stage, hormone sensitive breast cancer who opt for lumpectomy (not mastectomy).
How are outcomes compared to whole breast radiation therapy?
In the past three years we have treated close to 200 patients with no local recurrence of cancer. The original trial performed in Europe and the United States following approximately 1000 women over four years yielded nearly identical survival rates with non-inferior local recurrence rate—97.4% for IRT patients vs. 98.1 for those undergoing whole breast external beam radiation treatment.
Kaiser Permanente, kp.org