Intrabeam Photoradiosurgery System

Intraoperative Radiotherapy is a type of Partial Breast Irradiation in which the entire radiation therapy treatment is given during surgery, immediately following the removal of the breast cancer. Intraoperative Radiotherapy permits breast cancer surgery and radiotherapy to be given on a single day, instead of the usual practice of administering radiotherapy over 6-7 weeks after surgery.

Photo A

Photo B

Figure 1. Photo A shows the Photon Radiosurgery System. Photo B shows Intrabeam Photon Radiosurgery system covered by one of several different-sized applicators (arrow) designed to fit the lumpectomy cavity.

The Intrabeam PRS System is placed in the lumpectomy cavity following removal of the berast cancer (See Figure 2)

Drawing A

Drawing B

Figure 2. Drawing A showing breast and lumpectomy cavity (star) after removal of breast cancer. Drawing B shows Intrabeam Photon Radiosurgery System and applicator (arrow) positioned within the lumpectomy cavity. Bright red area shows portion of breast receiving the highest dose of radiotherapy

The Photon Radio System is capable of delivering radiation to the inside of the breast targeting breast tissue immediately surrounding the lumpectomy cavity. This permits the entire treatment to be given in a single dose. Also, since Targeted Intraoperative Radiotherapy can be placed dierctly into the lumpectomy cavity, radiotherapy can be given to the parts of the breast that need it most, while sparing the nearby normal breast, chest, and shoulder from the effects of radiation.

Single-Day Targeted Intraoperative Radiotherapy is designed to administer the highest dose of radiotherapy to a distance of 1cm (1/3 inch) surrounding the lumpectomy cavity. This portion of the breast is at the greatest risk of developing a breast cancer recurrence. As a result, this area is targeted for radiotherapy. Although the untreated parts of the breast may still may develop a breast cancer recurrence, we know that the vast majority of breast cancer recurrrences develop in the region of the breast immediately surrounding the original breast cancer. For this reason, the study investigators believe that Single-Day Targeted Intraoperative Radiotherapy may be safely given to women who have well defined, completely removed breast cancers.