Abstract
Breast cancer is the second most common cancer diagnosed among women in the United States following skin cancer. About one-third of women cancer patients have breast cancer. Following lung cancer, breast cancer has the second highest death rate compared to other types of cancer. Radiation therapy is a common way to treat breast cancer after surgery; it can significantly decrease the breast cancer recurrent rate. For early breast cancer treatment, breast-conserving surgery followed by radiation therapy is highly recommended compared to mastectomy. Since most of the local recurrences occur near the tumor bed, additional boost radiation to the tumor bed benefits patients of all age groups. In this dissertation, we developed an innovative imaging/therapy integrated system by using radionuclide Ir-192 for breast cancer. Three major studies have been completed. First of all, we proofed the possibility of using Ir-192 as an external source for breast imaging by Monte Carlo simulation. Secondly, we built an imaging assembly in a physical laboratory setting to further validate the imaging ability of Ir-192 source. Thirdly, a preliminary 3-D conformal treatment plan was created by using a commercially available treatment planning system to evaluate the treatment capability of using Ir-192 source in the future. Based on our studies, a new platform which combines imaging and treatment via a single radiation source (Ir-192) can potentially be implemented in the future for image-guided radiation therapy. In this context, patients are not required to undergo an external imaging modality to guide the brachytherapy treatment, so the dual-function radiation source can simplify the procedure and increase the efficiency. In addition, it will streamline the device and cut down the cost significantly.