On Target - Zooming in on Breast Cancer
Zooming in on Breast Cancer
Date: December 1, 2009
Meet Richard C. Zellars, M.D., assistant professor of oncology and radiation oncology in the Department of Radiation Oncology and Molecular Radiation Sciences at Johns Hopkins. We are proud to report that Dr. Zellars is a graduate of the Johns Hopkins University School of Medicine.
Board Certified by the American Board of Radiology in Radiation Oncology, Dr. Zellars has just completed a successful 25-patient Johns Hopkins clinical trial combining chemotherapy with partial breast irradiation (PBI) to treat breast cancer.
Before Dr. Zellars’ successful trial, the most common sequencing method of radiation and chemotherapy was chemotherapy first, followed by radiation. This sequential treatment lowered rates of toxicity but prolonged the overall treatment course.
Dr. Zellars decided to combine PBI with, arguably, the most common modern chemotherapy, dose-dense doxorubicin and cyclophosphamide.
Dr. Zellars’ team was the first to show that this combination of radiation and chemotherapy can occur with no toxic side effects. The most immediate benefit to women is that the overall breast cancer treatment time is reduced from what was commonly a five-to-six month treatment course to one that lasts less than two months, allowing women to get back to their fully active lives much sooner.
Dr. Zellars notes: “The research mission of our patient centered breast program is not only to facilitate breast radiation therapy, but, also, to increase its efficacy and, most importantly, safety.” Besides making combination therapy safe and effective for breast
cancer, Dr. Zellars is also investigating improving treatment by more accurately locating the lumpectomy cavity by applying PET scanning technology. With PBI, it is tremendously important to target the correct area to spare as much healthy tissue as possible.
Dr. Zellars and his team of medical experts at Johns Hopkins improved on the technique of tumor localization by using a PET scan, which is exceptionally good at picking up inflammation, to detect cancer in the body. The PET scan produces a 3-D image of the lump cavity after a lumpectomy has been performed. If the entire wall is inflamed, it can be used as a marker at which to aim radiation.
In his role as educator as well as clinician, Dr. Zellars is working with Johns Hopkins
engineering graduate students to develop a new ultrasound technique, ultrasound elasticity
Normal breast tissue, scar tissue, and the lump cavity all have different types of elasticity.
When women enrolled in the trial get a CT scan, they will also receive the new ultrasound to see if the ultrasound image can identify the cavity as well as, if not better than, the CT scan.
This is important because women receiving daily radiation treatments can be exposed to too much radiation when the targeted area has to be localized with frequent X-rays. An ultrasound image, however, may be able to provide a more precise target location than X-rays. An additional benefit is that this ultrasound technique can be used daily without any risk to the patient. As with Dr. Zellars’ PET scan improvements, USEI is leading to less healthy tissue being irradiated; a safer and more precise application of radiation.
Members of the Department of Radiation Oncology and Molecular Radiation Sciences at Johns Hopkins build on each other’s work to take cancer care to the next level. Dr. Zellars is presently conducting a cardiac tissue toxicity trial using a medical device created by his colleague, John Wai-Chiu Wong, M.D., who is also profiled in this issue.
Four years ago, scientists at Duke University demonstrated that radiation
delivered to the left breast decreased blood flow to the heart and caused heart problems 15 or more years after breast cancer treatment.
Meanwhile, Dr. Wong developed the Active Breathing Coordinator™ (ABC™), a device that allows the patient to hold her breath at a certain volume during treatment, allowing the chest wall to expand and move the breast away from the heart, and the heart away from the radiation.
Dr. Zellars has set out to prove that the ABC™ device prevents heart damage during left breast radiation treatment. One half of the female patients enrolled in the study are using the ABC™. All of the women had heart scans before receiving radiation and will have another heart scan six months after treatment ends. Changes in blood flow will be traced. This exciting trial should be finished by the end of the year.
We are pleased to announce Dr. Zellars’ latest Johns Hopkins clinical trial, which has just been funded and will begin shortly. Dr. Zellars and his research team will, for the first time, examine cytokines and their relationship to breast cancer and patient response to radiation therapy. Cytokines are proteins and peptides that help run cells. Certain cytokines are signs of the development of breast cancer, as others indicate radiation toxicity.
Dr. Zellars and his team will be taking blood to check cytokine levels. Changes caused by radiation will be predictive of toxicity and how patients will fare from treatment. All of Dr. Zellars’ clinical studies of breast cancer and related topics fit into the mission of the Department of Radiation Oncology and Molecular Radiation Sciences at Johns Hopkins, which is to discover and implement the best treatment for cancer patients.