When a woman is diagnosed with breast cancer, the treatment of preference is breast conserving therapy (BCT) with adjuvant radiotherapy. During BCT, titanium clips are placed in the excision cavity intraoperatively for postoperative localisation of the cavity. It is important to be able to accurately localize positive resection margins postoperatively, in order to make a plan for radiotherapy in which the tumour bed receives sufficient dose while dose on healthy tissue is minimized.
This has proved to be a great challenge. The most important reasons for this are the deformability of breast tissue and the inaccuracy with which the orientation of the lump is recorded. Therefore, a new method has been developed, 3D Margin Mapping (3DMaMa), to improve postoperative localization of positive resection margins. With 3DMaMa, clips are placed both in the excision cavity and on the lump. Thereafter, a 3D reconstruction of the lump is made. This method is already being tested on patients. It is important to verify whether 3DMaMa is superior to the conventional method. Our goal is to create an experimental setup which allows us to determine the difference between the expected and the true location of the positive resection margins, so that the deviation of 3DMaMa and of the conventional method can be compared.