External Beam

This treatment involves a Linear Accelerator, or "linac", that focuses the radiation from outside the body to the affected area of the breast. Depending on the size and extent of the cancer it can include the underarm and chest wall.

Patients who receive breast radiation after lumpectomy are usually treated 5 days a week (Monday through Friday) in an outpatient center for about 6 or 7 weeks, with each treatment lasting a few minutes.

Upon completion of the initial course of radiation a smaller, final, dose of radiation is given to the site where the tumor was removed. This final dose is called a "boost" or "booster dose", which may last from 1 to 2 weeks. This allows the radiation oncologist to deliver a higher total dose of radiation to the area where the tumor was removed. 

External beam radiation has been the standard of care for many years and has proven to be an effective treatment.

Some of the disadvantages to this type of therapy are excess radiation may be delivered to healthy tissue surrounding the treatment area, the overall length of the treatment and access to a treatment center.

Internal Radiation or Accelerated Partial Breast Irradiation (APBI)

Instead of a Linear Accelerator aiming radiation from outside the body, internal radiation, or partial breast irradiation, delivers the dose directly inside the body where the cancer was removed. This allows targeted radiation directly to the lumpectomy cavity and to a small area of tissue surrounding the cavity.

• Axxent Electronic Brachytherapy System is a newer form of APBI. Using a non-radioactive, electronic X-ray source, the system delivers high-dose-rate radiation directly to the lumpectomy site. This is done by inserting a thin catheter, tipped with a balloon, into the cavity left behind after the lumpectomy. The small X-ray tube travels down the center of this catheter and delivers radiation from inside the breast.  The treatment course is typically twice a day for five days. Due to the unique characteristics of the system, minimal shielding is required which can allow medical professionals to stay in the room with you during treatment. 
  
  Also, due to the unique characteristics of this system, less harmful radiation is delivered to surrounding healthy organs and tissue compared to other forms of APBI¹.
  
  
• Another form of ABPI uses a radioactive isotope to deliver radiation directly to the tumor site via a catheter placed inside the lumpectomy cavity. The treatment course is typically twice a day for five days.
  
  
• Interstitial brachytherapy involves the temporary placement of plastic catheters or needles directly into the tumor bed following lumpectomy. These catheters are then loaded with a radioactive isotope to deliver a targeted dose of radiation to the tumor. The treatment course is typically twice a day for five days.

Links to additional information

"Facts to Help Patients Make an Informed Decision"
"Your Partners in Cancer Treatment"