by Chester County Hospital
As more patients survive breast cancer, the long-term toxicities of their treatment are becoming more important.
"Our goal now, as we minimize the invasiveness of cancer treatments is to maximize the quality of life after the treatment," says Andre A. Konski, MD, Medical Director of Radiation Oncology at Chester County Hospital in West Chester, PA.
Breast cancer patients, specifically, who undergo radiation therapy are often exposed to incidental radiation doses to the heart and lungs. This can increase the risk for lung disease and ischemic heart disease (IHD), a condition where narrowing arteries allow less blood and oxygen to reach the heart. Ultimately, this can lead to a heart attack, especially in women suffering from left-sided breast cancer. A 2013 study published in The New England Journal of Medicine found that the increased risk begins within a few years after exposure and continues for at least 20 years.
But the combination of a groundbreaking technique and device is significantly reducing that risk. The moderate deep inspiration breath hold (mDIBH) used in conjunction with Elekta’s Active Breathing Coordinator (ABC), a noninvasive device that enables the patient to pause their breathing during radiation treatment to stop internal motion, allows the radiation beam to be applied with better precision.
What It Means
Radiation Therapy is essential in breast cancer treatment. In breast conservation therapy for invasive cancer and post-mastectomy radiotherapy for high-risk disease, it reduces the risk of local-regional recurrence and improves the likelihood of survival. The aim of such therapy is pretty straightforward: to deliver an optimal dose of radiation to the tumor while minimizing the dose to the surrounding healthy tissue. But it's a process made complicated by the proximity of critical organs which are constantly moving and adapting with normal functions.
With the ABC, the tumor is immobilized during the pause, allowing the clinician to maximize radiation to the site and also largely avoid the heart, lungs, and healthy tissue. A 2016 study in Practical Radiation Oncology found that the combination of the mDIBH and ABC reduced radiation to the heart, on average, by 20 percent or more in 88 percent of patients. This was achieved without any appreciable loss of coverage of the targeted tissue, a rate considerable enough to "justify routine use of ABC".
In fact, the ABC has been in routine use at Chester County Hospital since early this year. Dr. Konski says it has dramatically reshaped protocol; it is now used on every patient with left-sided breast cancer. "We're giving these women a greater opportunity to maximize their quality of life after their treatment has been completed," he says.
How It Works
This is how it works: By the patient holding their breath during the radiation therapy -- via the mDIBH -- the heart moves backward and downward, away from the breast area and out of the way of the radiation beam. When the radiation treatment is delivered, the patient uses a mouthpiece to breathe, and then a valve in the mouthpiece closes to help them hold their breath for about 20 seconds. After that time, the valve reopens and the patient can breathe normally.
If 20 seconds sounds a bit intimidating, it's only a benchmark. Throughout the treatment, the patient remains in control of the ABC by pressing a handheld thumb switch. If it's released at any time, the treatment stops and the mouthpiece valve opens so the patient can breathe normally again. Often, only a few pauses are needed. So, if a patient is ever struggling to hold their breath, or even suddenly begins to panic, they can halt everything without compromising the treatment.
As therapies continue to evolve at an incredible rate and in once unfathomable directions, cancer survivors are living far longer than they were just a decade or two ago. Priorities are evolving, too. Now, instead of simply combatting the cancer, physicians like Dr. Konski and researchers are concerning themselves with preserving the quality of life on the other side of that treatment. The mDIBH and ABC combination is among the first of what are likely to become a steady procession of strides toward that end.
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