Newswatch: March 2006

One-day breast-cancer treatment may be possible, according to new study

Physicians in Canada are studying the effectiveness of permanent radiation seed implants following lumpectomy as an alternative to whole or partial breast irradiation for early-stage breast-cancer patients. This type of radiation would cut treatment time for certain patients from several weeks to 1 day.

For early-stage breast cancer, women often undergo a lumpectomy to remove the tumor followed by radiation therapy to kill any cancer cells that could remain. Most women undergo external beam radiation therapy (EBRT), which is given every day, Monday through Friday, for 6 to 8 weeks. Physicians have been experimenting with ways to shorten this treatment. One technique used by a growing number of radiation oncologists involves the use of temporary radiation implants. These radiation sources are delivered through a catheter into the breast, usually twice per day for 1 week.

In this ongoing study, the first of its kind, researchers wanted to see if it was possible to use permanent implants—similar to what many men receive for treating prostate cancer—to combat the cancer with only one treatment. These implants, about the size of a grain of rice, would not be removed daily like with the temporary implants. Instead, the radioactive seeds would deliver radiation to the breast area for a number of weeks until they were no longer radioactive. The advantage over the temporary implants is that the patient has to undergo only one surgical procedure to receive the radiation, versus 10 treatments over 1 week for temporary implants.

The current treatment standard of lumpectomy followed by EBRT is proven to keep the cancer from returning, but 38% of women develop significant toxicity, which can compromise their quality of life. According to early returns from the study, which began in May 2004, 44 patients have been treated successfully with the permanent implants. So far, none have evidence of their cancer returning, and acute skin irritation is 6 times less frequent when compared to EBRT.

"The main motivation was to see if we could reduce the burden of treatment for women suffering from early-stage breast cancer," said Jean-Philippe Pignol, MD, PhD, lead author of the study and radiation oncologist at Sunnybrook and Women's College Health Sciences Centre (Toronto). "The seed implants reduce the treatment to a one-time event compared to the current standard of daily treatments over many weeks. The seeds also reduce the amount of radiation that the normal breast tissue receives, which lessens the chance of the patient developing problems that affect their post-cancer quality of life. The great thing is that the patient can go home right after the procedure and live a normal life, while receiving her radiation."

Preliminary results of the study, "First Report of a Permanent Breast PD Seed Implant as Adjuvant Radiation Treatment for Early-State Breast Cancer," were discussed and published in the January 1, 2006, issue of the International Society for Therapeutic Radiation Oncology*Biology*Physics, the official journal of the American Society for Therapeutic Radiology and Oncology (ASTRO of Fairfax, Va). For more information on radiation therapy for breast cancer, please visit www.rtanswers.org.