An international randomised controlled trial to compare targeted intra-operative radiotherapy boost with conventional external beam radiotherapy boost after lumpectomy for breast cancer in women with a high risk of local recurrence.
Women diagnosed with breast cancer usually have an operation to remove the whole breast (mastectomy) or just the tumour (lumpectomy). Following surgery, many women have radiotherapy to the operated breast or chest wall. This treatment aims to prevent cancer returning by killing any cancer cells in the remaining breast tissue and nearby lymph nodes (under the arm, for example). It takes 3-5 weeks, depending on the schedule used.
Some patients with more aggressive cancers receive additional radiotherapy, called a boost. This is given to the part of the breast that used to contain the tumour, to increase the chances of killing any remaining cancer cells. It requires 3-8 extra visits to hospital, depending on the schedule used.
Experts have developed a way to give boost radiotherapy during surgery. After the tumour has been removed, radiotherapy is given directly to the remaining breast tissue using specially designed equipment. The breast is then sewn together as normal.
Giving boost radiotherapy during surgery may have some advantages. The surgeon is able to place the equipment directly onto the breast tissue that surrounded the tumour, ensuring it all gets irradiated. Breast tissue swells up with fluid after surgery as part of the healing process. This fluid is slowly absorbed back into the body and some experts think that any cancer cells left in the breast could be absorbed into the body with it. Receiving boost radiotherapy during surgery may kill these cells before they are absorbed. Patients may find this treatment more convenient as they will not have to make the extra 5-8 visits to hospital afterwards.
TARGIT-B aims to examine whether intraoperative boost radiotherapy is as effective as standard boost radiotherapy. Women who are at increased risk of their cancer returning following lumpectomy are eligible to take part.
Participants will be randomised in equal numbers between two treatment arms:
SHORE-C is interested in examining QoL aspects of these treatments. Radiotherapy given after surgery for breast cancer can have long term effects on arm and shoulder movement and cause painful swelling of the arm. Intraoperative radiotherapy delivers an intense radiation dose which could be harmful to skin. Previous research suggests that this more intense radiotherapy does not interfere with surgical wound healing or lead to any permanent skin changes, however we will be able to examine this more fully in Targit-B.
We will measure QoL using the FACT B+4 questionnaire which has been specifically designed for patients following surgery and radiotherapy for breast cancer. We will also measure daily living activities using the EQ-5D questionnaire. Participants will be asked to complete these questionnaires before randomisation, 6, 12, 18, and 24 months later, then annually for a further three years (8 times altogether).