New Breast Cancer Imaging During Treatment

There’s a new non-invasive technology to help conquer a little-known problem in breast cancer treatment, and I asked a radiation oncologist some questions to help us better understand the development.

Many breast cancer patients aren’t aware that their lumpectomy cavity — or area where the cancerous tumor was removed from — can move and change shape from day-to-day after surgery and before radiation treatment begins. Lumpectomy cavity movement makes delivering targeted radiation more difficult, possibly leading to under-treatment or to unnecessary exposure of healthy tissue to radiation.

Physicians are beginning to address the challenge of lumpectomy movement with a new FDA-cleared application of 3-D ultrasound called the Clarity Breast System. The system helps doctors locate the tumor cavity in real-time during planning and treatment.

Dr. Joseph Imperato, a radiation oncologist and medical director of radiation oncology at Lake Forest Hospital in Lake Forest, Illinois, answered my questions about the Clarity Breast System. Dr. Imperato relates why he believes the new system is beneficial to breast cancer patients and further explains how this 3D-ultrasound technology is being applied for the first time in the planning and treatment of breast cancer.

As a radiation oncologist, do you prefer working with the 3-D ultrasound technology of the Clarity System over other methods for locating a lumpectomy cavity? If so, how does it help you tailor treatment?

Dr. Joseph Imperato: Given the extended duration of a course of radiation treatment, a practical solution to the problem of lumpectomy cavity movement is to visualize the cavity on a daily basis prior to delivering radiation to ensure precise targeting. For many years, we relied solely on computed tomography (CT) imaging as the standard tool used for radiation treatment planning. However, CT is limited in its ability to visualize certain soft tissues, such as lumpectomy cavities, particularly in its ability to distinguish them from the adjacent scar or normal tissue. Historically, in the treatment room, physicians have relied on the surgery scar to serve as a marker to localize the lumpectomy cavity. Several studies have found that locating the lumpectomy cavity based solely on this scar may result in a partial miss of the cavity in over 50 percent cases. We have the capability of doing daily X-rays in the treatment room to try to see the cavity, but the images are often unclear, and this is extra radiation that we definitely want to avoid in breast patients. With a lack of alternatives for ensuring precision, many physicians have no option but to expand the treatment margins to accommodate for this movement, exposing additional healthy tissue to radiation.

3D-ultrasound such as the FDA-cleared Clarity System is a much-needed alternative for addressing lumpectomy cavity changes. Ultrasound is a proven technology that many patients may positively associate with memories of pregnancy and the first images of their unborn babies. What’s more, it is a gentle imaging alternative with no radiation and no need to place anything inside the patient. With Clarity, 3D ultrasound is used to visualize the cavity at the time of planning to make sure we target the right areas for treatment. Then at the time of treatment, we reuse Clarity to make sure we are hitting that target every day. For the first time, radiation oncologists are able to increase their certainty and confidence in treating the target in the breast, without any added imaging radiation dose. This confidence could allow radiation oncologists to tighten the margins we are treating, resulting in reduced radiation exposure to the surrounding healthy tissue.

Why it is important to image the tumor cavity daily?

Dr. Joseph Imperato: Clinical evidence suggests that patients who are diagnosed early respond well to breast conservation treatment, a lumpectomy followed by a course of radiation treatment with a very targeted boost at the end of the treatment to minimize the chance of recurrence. While we all understand that radiation is necessary to destroy cancerous cells, both patients and their physicians often worry about the side effects of radiation to healthy tissue and the organs near the breast. The fact that a breast lumpectomy cavity can move or change shape within days and weeks of surgery makes this issue all the more complex.

Changes in size, shape and location of the lumpectomy cavity can occur due to tissue healing and scarring, as well as daily patient setup, which can put the patient at risk for under-treatment of the target or unnecessary radiation exposure to healthy tissue. The Clarity System visualizes the precise location and size of the tumor cavity during treatment planning and then daily in “real time,” with each targeted boost portions of treatment. Patients gain the peace of mind that their radiation treatment is being delivered directly to the area where it is needed most while minimizing exposure to healthy tissue.

Does the use of Clarity System require additional visits to a medical office or hospital?

Dr. Joseph Imperato: No, the Clarity System does not require the patient to come in for additional visits. During radiation treatment planning, Clarity is used to create an ultrasound-CT fusion image, which is then compared to daily ultrasounds taken on each consecutive day of radiation treatment, to get an actual visual image and location of the tumor cavity on a regular basis. This makes it more practical for the patients and for our staff since no additional appointments are required.

Many women are familiar with ultrasounds, but how is a 3-D ultrasound system different from traditional ultrasounds?

Dr. Joseph Imperato: Most women associate an ultrasound with the memories of seeing their unborn child for the first time. However, many women are not aware of the important role that ultrasound plays in the detection and, more recently, even in the treatment of breast cancer. Ultrasound is used because it is a very easy way of clearly seeing soft tissue structures, like breast tumors or cavities. It is advantageous because, unlike X-rays, it does not involve any radiation to the patient. It is also an affordable solution that is easy to implement in hospitals. With the Clarity System, 3D-ultrasound technology is being applied for the first time in the planning and treatment of breast cancer.

In general, do health insurance companies typically cover the use of Clarity System during breast cancer treatment?

Dr. Joseph Imperato: Image guided radiation therapy (IGRT) with the Clarity System is covered by many insurance companies who recognize it as an integral part of any targeted treatment.

(Image via Resonant)