Standard treatment for early-stage, estrogen-receptor-positive breast cancers consists of lumpectomy to remove the cancer followed by approximately 6 weeks of radiation therapy (5 days a week) to destroy any cancer cells that may have been left behind. This two-step approach reduces the rate of breast cancer recurrence (the cancer coming back).
But in 2004, this treatment approach changed for older women. Large studies showed that while lumpectomy plus radiation did reduce the rate of recurrence among older women, it didn’t improve their overall survival. Overall survival is the amount of time the women lived, with or without the cancer coming back. So the National Comprehensive Cancer Network (NCCN) modified its treatment guidelines: it made radiation therapy optional for women age 70 and older.
There was debate about the change and many doctors had questions about the potential benefits of radiation for this group of women. So to learn more, researchers looked at the effect of the NCCN recommendation on the use of radiation therapy and on overall survival in older women.
The results were presented at the 2012 American Society for Radiation Oncology Annual Meeting. The researchers found that the treatment guideline change meant that fewer older women diagnosed with early-stage breast cancer were receiving radiation therapy, particularly if they were older than 80.
One study looked at treatment information from 13 NCCN institutions collected from 2000 to 2009. This included information on 1,292 women age 70 and older diagnosed with early-stage breast cancer:
- 94% of women age 70 to 74 got radiation therapy in 2000 compared to 88% in 2009
- 80% of women age 80 and older got radiation therapy in 2000; only 38% did in 2009
Using information from SEER, a large registry of cancer cases from sources throughout the United States maintained by the National Institutes of Health, another study found that:
- 72% of women age 70 or older got radiation therapy from 2000 to 2004 compared to 66% of women from 2005 to 2008
- women age 80 and older (a third of the women in the study) were less likely to get radiation therapy
Despite the overall drop in radiation therapy for older women, some institutions continued to routinely use radiation therapy even after the guideline change. Some cancer centers were up to 10 times more likely than other centers to use radiation therapy to treat older women, even though all the centers followed the same treatment guidelines.
Because these studies had a long follow-up time, it was easy to see the benefits of radiation therapy for older women.
In the study using information from the SEER database:
- cancer-specific survival after 8 years was better in women who got radiation therapy after lumpectomy (95%) compared to women who got only lumpectomy (91%)
- overall survival after 8 years was better in women who got radiation therapy (73%) compared to women who didn’t (49%)
Cancer-specific survival means the women didn’t die from breast cancer. Overall survival means the women didn’t die from breast cancer or any other cause.
Women who got radiation therapy were more likely to be younger than 80, which also could have affected the outcome.
A different study also analyzed the SEER database information and found similar outcomes. Both cancer-specific survival and overall survival were better in women treated with lumpectomy plus radiation:
- overall survival at 10 years was 65% in women who got lumpectomy plus radiation compared to 42% in women who got only lumpectomy
- overall survival at 15 years was 40% in women who got lumpectomy plus radiation compared to 20% in women who got only lumpectomy
These results strongly suggest that the NCCN guidelines may not be appropriate for all older women diagnosed with early-stage breast cancer. Radiation therapy offers benefits to many older women diagnosed with early-stage breast cancer, including lower recurrence rates and better overall survival.
If you’re 70 or older and have been diagnosed with early-stage breast cancer, you and your doctor will consider the characteristics of the cancer, your unique situation, your surgical options, and your treatment options after surgery when creating your treatment plan. If you’ll be having lumpectomy and radiation therapy isn’t recommended, you might want to talk to your doctor about these studies and ask why radiation therapy after surgery isn’t recommended for you.
Using the most complete and accurate information possible, you and your doctor can develop a treatment plan that makes the most sense for you. You can learn more about radiation after breast cancer surgery in the Breastcancer.org Radiation Therapy section.