“Breast Radiation in One Day With IORT”

By Sachin Kamath,  MD

Traditionally, early-stage breast cancer treatment has been treated with surgery (usually lumpectomy) and six weeks of whole breast external beam radiation therapy, either with or without chemotherapy or hormonal therapy.  Not all patients who choose lumpectomy comply with the recommended follow-up radiation treatment because of factors relating to time, money, distance and access to a radiation center.  Neglecting follow-up radiation therapy after lumpectomy can increase the risk of cancer recurrence.   Fortunately, today there is another newer method of delivering radiation to the breast after lumpectomy—intraoperative radiation therapy (IORT)--that allows for a more expedited, convenient treatment schedule.

IORT has been performed successfully over the past several years with good results, but very few centers around the country could afford to have the specially shielded operating rooms that were necessary.  With the advent of electronic  brachytherapy  technology,  like the Xoft eBx  system,  IORT can now be more easily performed  since  a shielded vault is not required.  With breast IORT, the radiation is delivered in a single treatment right to the target tissue (lumpectomy cavity) in the operating room at the time of surgery.  The rationale for IORT is to deliver a high dose of radiation precisely to the target area with minimal exposure to surrounding tissues, which can be displaced or shielded during the IORT procedure.  With conventional radiation techniques after lumpectomy there are some drawbacks. First, the tumor bed, where the highest radiation dose should be applied, can be missed due to the complex localization of the wound cavity even when modern radiotherapy planning is used. Second, the usual delay between surgical removal of the tumor and radiation treatment may allow for repopulation of tumor cells.  These potentially harmful issues can be avoided by delivering IORT directly to the target tissues with IORT, leading to immediate sterilization of any residual tumor cells.  With the Xoft eBx system, a typical IORT treatment for breast cancer can be completed in as little as eight minutes.

Today, more than ever, one of our primary goals in cancer treatment is to provide better targeted therapies.  One of the most exciting innovations in breast cancer treatment recently is intraoperative radiation therapy (IORT).

 Last year, a landmark breast IORT study (TARGIT trial) published in the journal Lancet offers tremendous hope that a single radiation treatment at the time of lumpectomy might be able to replace the more cumbersome and time-consuming radiation treatment options commonly used today to treat patients with early stage breast cancer.  If the excellent results with breast IORT hold up long-term, as hoped and expected, then this approach to early stage breast cancer treatment has the potential to significantly increase the speed and efficiency of patient care while at the same time decreasing the overall cost of care.

Unfortunately, not all patients with early stage breast cancer are candidates for IORT because of technical and/or anatomical difficulties.  However, if we continue our efforts to catch more cases of breast cancer in the earlier stages, then breast IORT using the Xoft eBx system has the potential to improve the quality of the lives of millions of patients over time by freeing them up  to move on with their lives more quickly after receiving the breast cancer diagnosis. 

Two bay area institutions, Stanford and UCSF, participated in the TARGIT study.  Diablo Valley Oncology, a UCSF research affiliate, has been using the Xoft electronic brachytherapy technology for two years and is partnering with local breast surgeons to offer the breast IORT procedure beginning in December 2011 at the Aspen Surgery Center.  Diablo Valley Oncology will be the first practice in the East Bay to offer this procedure to breast cancer patients.