About Partial Breast Irradiation



A typical course of radiation therapy following breast cancer surgery involves 35 daily sessions over seven weeks. But for certain women undergoing lumpectomy, a new radiation technology is allowing a faster return to normal life, with fewer side effects.

In accelerated partial breast irradiation (APBI), a balloon filled with saline is temporarily embedded in the lumpectomy site following excision of the tumor. After careful planning, a radiation source is inserted into the balloon to deliver a sphere of radiation to the surgical cavity twice a day. Each treatment session takes about ten minutes, and the entire course of therapy is completed in just ten sessions over five days.

“Radiation is delivered precisely to where a residual microscopic tumor is most likely to be,” explains Robert L. Hong, MD, Medical Director of Radiation Oncology. “Over 95 percent of recurrences occur in the same quadrant of the primary tumor, typically within one centimeter of the initial malignancy.”

The targeted nature of APBI also means less damage to healthy tissue, and therefore fewer side effects such as fatigue and skin burns.

“The idea is that we can reduce the total volume of radiation by concentrating on the area of greatest risk (the tumor bed) without radiating healthy tissue,” explains radiation oncologist Robert L. Hong, MD.

With the acquisition of MammoSite®, Contura and SAVI applicators, all leading brands of APBI technology, Virginia Hospital Center is the only medical facility in Northern Virginia offering this cutting-edge procedure using all available applicators. Virginia Hospital Center also just upgraded to the newest planning software in June 2009. But APBI is not for everyone. To qualify, candidates typically must be 45 years or older with a single, small tumor (less than 3 cm in diameter), no evidence of metastasis, and a tumor cavity that is at least 7mm from the skin.

Women with multiple tumors or cancers that involve the lymph nodes are more likely to benefit from standard whole breast external beam radiation, which delivers a uniform dose to the entire affected area following mastectomy or lumpectomy. This approach may utilize intensity modulated radiation therapy (IMRT), which often results in a more uniform dose and reduces “hot spots” in the breast.

A current national clinical trial is investigating potential future applications of APBI in younger women and cases where cancer has spread to the lymph nodes.