Respiratory Gating Techniques for better breast cancer treatment
For women diagnosed with cancer in their left breast, during the treatment they are exposed to incidental dose of radiation to the heart. To avoid, this incidental radiation dose to the heart, new technological advancements have been made with “Respiratory Gating Techniques” wherein the TrueBeam STx radiation technology recognizes this phase of breathing in the patient and treatment happens only when she is holding her breath in that phase. This reduces the incidental radiation dose to the heart of the patient, diagnosed with cancer in her left breast, leading to better quality of life post cancer treatment.
Dr. J Mathangi, Consultant, Radiation Oncologist, BGS Global Hospitals presents her insight into this new technology. With increased awareness and accessibility of screening techniques more women are diagnosed with early stages of breast cancers. The advances in treatment assuring improved survival in early stages, the goal in present era of cancer therapy is slowly shifting from not just curing but also improving the quality of life after cancer treatment.
A woman diagnosed with breast cancer treatment will have to undergo surgery for the removal of the cancerous lump followed by chemotherapy and radiotherapy depending upon the size and stage of the tumor. The combination of treatments amidst the background of pre-existing diseases like diabetes, hypertension and obesity warrants us to concentrate more on reducing long term side effects in such patients.
The breast cancer patients with left sided disease were found to have lesser survival comparatively. Along with the cardio-toxic chemotherapy drugs, incidental radiation to the heart and especially to the left anterior descending artery, one of the main coronary arteries, also plays a probable role for the long term cardiac morbidity.
New methods are being invented everyday all over the world to reduce this incidental dose to the heart. In the deep inspiration phase, the heart becomes globular and shifts away from the left chest wall. So treating the breast and chest wall in such a phase helps us reduced the dose to heart in a simpler way. The 4D CT scan, an improved version of the present day radiotherapy planning CT scan, is done in the deep inspiratory breath hold phase. The gating software in the TrueBeam STx machine recognizes this phase of breathing in that patient and treatment happens only when she is holding her breath in that phase.
Kamal Deep Peter, a 53 year old lady was diagnosed with a lump in the left breast and was operated one year ago for the same followed by chemotherapy. When she came for radiation she was trained for a week for holding her breath in deep inspiratory phase and a 4D CT scan was done in this phase. In the CT scan there was a gross shift of heart away from the chest wall and the left anterior descending artery was totally out of the radiation field. She received very less dose to the heart when compared to her usual treatment methods.
She was very cooperative and felt very happy to be participating and contributing to her own treatment. She also had visual feedback regarding how well she was performing during the training. This helped her cooperate well during the training and treatment. She felt the technique was very simple, effective and not very cumbersome to practice. She also felt very comfortable when doing the same. She completed her treatment and under regular follow-up with the disease in complete remission and with a good quality of life.