Women diagnosed with early-stage breast cancer who got a lower dose of radiation therapy for a shorter time after lumpectomy had the same outcome as women who got standard radiation therapy treatment (a higher dose for a longer time).
The results were presented at the 2008 American Society for Therapeutic Radiology and Oncology meeting.
Radiation therapy after breast cancer surgery is usually given as 25 treatments -- you're treated 5 times per week for 5 weeks. A Gray is the way radiation oncologists measure the dose of radiation therapy; 50 Gray is the usual amount given during the 5 weeks.
More than 1,200 women participated in this study. All of them were diagnosed with early-stage breast cancer with no lymph node involvement and all had lumpectomy. Half of the women then got standard radiation therapy (a total of 50 Gray of radiation over 5 weeks). The other half got a shorter course of radiation therapy (a total of 42.5 Gray of radiation over 3 weeks). Because the short course of radiation therapy was given over only 3 weeks, the amount of radiation given at each treatment was higher than the standard treatment. The doctors wanted to find out if this would cause more side effects. Overall, the total amount of radiation therapy given with the short course was lower than the standard course (42.5 Gray instead of 50 Gray).
The researchers followed the women for 10 years after the radiation therapy was completed and compared the women who got the short course to the women who got the standard course. The results:
- The risk of breast cancer coming back was about the same no matter which course of radiation therapy a woman got. Over 10 years, 6.2% of the women who got the short course had the cancer come back, compared to 6.7% of the women who got the standard course.
- The chances of good or excellent cosmetic results were the same.
- The risk of moderate or severe skin problems were similar.
- The risk of moderate or severe problems in the tissue under the skin (subcutaneous tissue) were similar.
Scheduling daily trips to the doctor's office for radiation therapy treatment is a problem for some women. Because it means fewer office visits, the shorter course may be easier to schedule. The shorter radiation course is common after lumpectomy for early-stage breast cancer with no lymph node involvement in Canada, but isn't as popular in the United States.
The results of this study are similar to those from other research. Still, more research is needed before shorter radiation therapy schedules are more widely used. If radiation therapy is part of your treatment plan, you might want to talk to your doctor about this study and if a shorter radiation therapy course makes sense for your unique situation. Together, you and your doctor can make the best choice for YOU.