APBI: A Newer Treatment for Breast Cancer
|After a breast cancer diagnosis followed by surgery and partial breast irradiation, Kathryn Steyer, shown with grandson Gibson, is back enjoying life.
Last September, 62-year-old Kathryn Steyer of Greenville heard the news every woman dreads: a breast biopsy revealed she had invasive lobular cancer. The diagnosis came as a complete shock.
Kathryn was discouraged to learn the type of breast cancer she had was fairly aggressive. But she and her doctors were hopeful about a recovery because it was caught early due, in part, to digital mammography – an advanced form of mammogram offered by Miami Valley Hospital.
“It was just a slight shadow. No one even felt a lump,” says Kathryn. “If I hadn’t had a digital mammogram, they might not have seen it.”
The next series of appointments felt like a whirlwind to Kathryn as she learned more about the options for breast cancer treatment. She did some basic research on her own but waited for more information about the specific characteristics of her cancer before considering her options.
Radiating Less Breast Tissue
After a lumpectomy and further testing, Kathryn received some good news. Not only were her lymph nodes free of cancer, but she was a candidate for a newer form of post-operative radiation treatment called Accelerated Partial Breast Irradiation (APBI).
Rebecca Paessun, MD, a radiation oncologist at MVH and clinical assistant professor atWright State University Boonshoft School of Medicine, explains that the concept behind APBI is that radiation can be delivered to only that portion of the breast that contained the tumor (the lumpectomy cavity) and a small area surrounding it.
“Studies indicate that most local recurrences – after lumpectomy and traditional whole-breast radiation treatment – occur in the original tumor site and usually not elsewhere in the breast,” says Dr. Paessun.
While Dr. Paessun says APBI shows great promise for women who want to avoid whole-breast radiation and weeks of daily treatment, there is limited longterm data about APBI available compared to data on traditional whole-breast radiation.
As Dr. Paessun explains, “In carefully selected women with early-stage breast cancer, preliminary data reveals similar results with APBI and whole-breast irradiation.”
There are several ways to deliver APBI. Balloon brachytherapy (i.e., seed implantation) is a common technique in which a catheter – or channel – with a balloon on the end is inserted into the lumpectomy cavity. The balloon is then inflated with water.
During treatment, a computercontrolled radioactive “seed” is passed through the channel into the balloon. The seed is left inside the balloon for several minutes and then removed. The balloon remains within the cavity for the remainder of the patient’s radiation treatment.
Radiating for Fewer Days
|Dr. Paessun displays the balloon brachytherapy device used to implant radioactive seeds into the lumpectomy cavity.
Traditional radiation treatment requires a significant adjustment to one’s lifestyle for up to five to seven weeks and can produce unpleasant side effects, such as fatigue and skin reactions.
In comparison, APBI with balloon brachytherapy requires only five days of twice-daily radiation. Patients undergo their first treatment in the morning and then return in the afternoon for another dose of radiation. Another benefit of APBI is a decreased chance of side effects.
Kathryn, a retired teacher, enjoys a busy life, including conducting school tours for Brumbaugh’s Fruit Farm, so she was happy she was a candidate for APBI. “I was grateful I would need only five days of treatment,” she says.
Although having breast cancer took an emotional toll on Kathryn, her husband and their family and friends, she still can’t believe how short the entire ordeal was. “It was only 30 days from the time I received the phone call about my breast cancer diagnosis until my last day of treatment. Looking back, it seems like a blink of an eye,” she says.
Since Kathryn lives in Greenville, she remained in Dayton during her APBI treatment. She spent time reading or shopping until it was time for her next treatment. Kathryn had watched two sisters-in-law endure lengthy radiation treatments, and that made her own treatment seem more convenient and easier in comparison. “It actually wasn’t too bad at all,” she says in retrospect.
One treatment of APBI with balloon brachytherapy takes about 20 to 30 minutes. Dr. Paessun says it’s critical that patients receive a limited CT scan prior to each treatment to ensure the balloon didn’t shift within the breast and its volume remained the same. “The breast tissue must conform around the balloon,” explains Dr. Paessun. “There can be no significant gaps between the balloon and breast tissue.”
These scans also guide Dr. Paessun’s radiation prescription, including the dosage and time the radiation seed remains in the balloon. Although the number of APBI treatments differs dramatically from traditional wholebreast radiation, the amount of
radiation used is thought to be biologically comparable.
Candidates for APBI
Dr. Paessun emphasizes that not all women with a diagnosis of breast cancer are candidates for APBI treatment.
- A woman should be at least 45 years old. Because younger women have a potentially higher risk of breast cancer reoccurrence, early APBI studies did not include them; therefore, there is limited data on the effectiveness of APBI on younger-age groups.
- Candidates for APBI should have a solitary legion – only one cancer site within the breast – that is less than or equal to three centimeters.
- If cancer exists in the lymph nodes, APBI is not an option, unless the patient is enrolled in a clinical trial.
- The margins around the cancer must also be clear. Preferably a two-millimeter area surrounding the cancerous tissue should be clear of cancer cells.
- The size of the tumor in relation to the size of the breast is also a consideration.
- Patients who test positive for genetic mutations (known as BRCA I and II) should not have APBI. Because such mutations put a woman at higher risk for breast cancer recurrence, more aggressive therapy is indicated.
Dr. Paessun says enhancements are being made by companies that produce balloons for APBI, including larger sizes and different shapes. Some balloons now contain additional interior channels, as well as a channel designed for removing air and fluid around the balloon. These improvements are increasing the number of women eligible for APBI with balloon brachytherapy
and decreasing potential complications.
Besides advances in APBI technology, Dr. Paessun reports that improved diagnostic tests are providing better courses of treatment; and medications taken after breast cancer treatment to reduce the risk of reoccurrence continue to show promise.
|Retired from teaching and recovered from breast cancer, Kathryn Steyer is looking forward to many years as a healthy grandmother.
Such advances are improving the chances for survival for women diagnosed with breast cancer. At MVH, they will find up-to-date technology and skilled medical professionals – doctors, including oncologists and surgeons; physicists, dosimetrists, who calculate the dose of radiation; radiation therapists and specially trained oncology nurses – to help them fight their disease.
Kathryn has high praise for the staff at MVH. “Breast detection and treatment could become routine for them, but they didn’t lose sight of how personal it was to me. They were genuine and caring.”
All Women Are at Risk
It’s well known there’s a link between genetics and the risk of developing breast cancer. But Dr. Paessun warns against a false sense of security among women who have no genetic risk: “Breast cancer is the most common type of female cancer in the U.S. and the second most common cancer death in women. One in eight women in the U.S. will develop invasive breast cancer, but up to 80 percent of those diagnosed have no genetic history of the disease.”
Dr. Paessun stresses that the American College of Radiology recommends annual mammograms for all women age 40 and older, not just those who have a higher risk for breast cancer. For women at high risk, their physicians may recommend screening examinations at an earlier age.