A study suggests that having mammograms twice per year after lumpectomy finds a cancer recurrence (or a new cancer) earlier than only one mammogram per year after surgery.
A woman diagnosed with early-stage breast cancer who has lumpectomy to remove the cancer usually has radiation therapy after surgery. Her treatment plan also may include chemotherapy and hormonal therapy. These treatments are given after lumpectomy to lower the risk of the cancer coming back (recurrence). Still, breast cancer recurrence does happen.
Also, the risk of developing a new, second breast cancer in the same or opposite breast is much higher than average after being diagnosed with breast cancer. About 10% to 20% of women who have lumpectomy to remove early-stage breast cancer will have a recurrence of that cancer or develop a new, second breast cancer.
Doctors often recommend an aggressive screening plan after lumpectomy to make sure that any new or recurring breast cancer is found early, when it's most treatable. This might mean having mammograms more often than once per year, which is the recommendation for women 40 and older with average breast cancer risk.
In this study, researchers looked 10,750 mammograms done in 2,329 women who had lumpectomy to remove early-stage breast cancer between 1997 and 2008. After surgery, it was recommended that all the women have two screening mammograms per year. Five years after surgery, most mammograms were being done twice per year, but about 10% were being done only once per year.
The mammograms found 158 breast abnormalities and 114 of these (72%) were breast cancer. The researchers compared the characteristics of the breast cancers found by mammograms done twice per year to cancers found by mammograms done only once per year.
Cancers found by mammograms done twice per year were:
- More likely to be stage 0 or stage 1: 94% of cancers found by twice-yearly mammograms were stage 0 or stage 1 compared to only 73% of cancers found by once-per-year mammograms. Generally, the lower the cancer's stage at diagnosis, the easier it is to treat and the better the prognosis.
- Smaller in size: Cancers found by twice-yearly mammograms were about 11.5 millimeters (mm) in size compared to an average of 15.3 mm for cancers found by once-per-year mammograms. Generally, the smaller the cancer at diagnosis, the easier it is to treat and the better the prognosis.
- More likely not to have spread to nearby lymph nodes: 98% of cancers found by twice-yearly mammograms hadn't spread to nearby lymph nodes (called node-negative) compared to 91% of cancers found by once-per-year mammograms. Generally, node-negative breast cancers have a better prognosis than cancers that have spread to the lymph nodes.
These results suggest that cancers found by mammograms done twice per year after lumpectomy may have a better prognosis than cancers found by mammograms done once per year after lumpectomy. Still, the study only looked at the characteristics of the cancers at diagnosis, not the treatment outcomes. So we don't know if women who had two mammograms per year after lumpectomy had better survival compared to women who had only one mammogram per year after lumpectomy. More research, including looking at treatment outcomes, is needed before we know for sure that two mammograms per year after lumpectomy should be the standard.
If you've been diagnosed with early-stage breast cancer and are having lumpectomy, you and your doctor likely will develop a screening plan that's more aggressive than average to find any cancer recurrence or a new, second breast cancer. Your plan may include frequent exams by your doctor, breast self-exams, mammograms, or other imaging tests, such as MRI. The study reviewed here suggests that two mammograms per year after surgery may make sense. Sticking with your screening plan is just as important as making the plan. After your treatment is done, you may be tempted to skip some follow-up screening tests. Don't -- there's only one of you, and you and your future deserve the best care possible.
It's also important to do all you can to lower your risk of recurrence or a new, second breast cancer. Visit the Breastcancer.org Lowering Risk for People with a Personal History page to learn more.