Results of a study presented at this month’s San Antonio Breast Cancer Symposium disrupts traditional thinking about the long-term survival rates of breast-conserving therapy (lumpectomy and radiation) compared to mastectomy for early-stage breast cancers.
Using the medical records of 37,207 women who were diagnosed with early-stage breast cancer between 2000 and 2004, Dutch researchers found that 76.8% of women who had breast-conserving therapy survived for at least 10 years, compared to just 59.7% of women who had mastectomy. This study was observational: researchers only looked at survival rates; they didn’t analyze factors like other health conditions or family history, for example, that may have affected patient survival. (Women who fared better tended to be younger and had less threatening tumor characteristics; researchers corrected for tumor size and nodal status.)
These results are somewhat surprising, since for many years, standard thinking has been that survival rates for the two types of treatment were about the same. Although other observational studies have reached different conclusions when comparing survival rates between lumpectomy with radiation and mastectomy, some randomized clinical trials—the best kind of research—found that survival rates were about the same, but they didn’t assess post-treatment longevity beyond 5 years.
Mastectomy rates in the U.S. have been steadily rising for the past decade. More women who have early-stage breast cancer and are candidates for lumpectomy and radiation—those who have stage I or stage II breast tumors that are smaller than 5 centimeters and are contained within the breast—are choosing mastectomy instead. This study suggests that may not be the best long-term choice.
Women who choose mastectomy over breast-conserving therapy have different reasons for doing so: they want to avoid having radiation, they don't live near a facility that offers radiation therapy, or they erroneously believe that mastectomy will eliminate all possibility of recurrence. It doesn’t, because it is impossible to surgically eliminate every bit of breast tissue or every breast cancer cell.
Additional research is needed to corroborate these findings, this study does underscore the widespread philosophy in the medical community that for someone with early-stage breast cancer, especially those with small tumors, breast-conserving therapy is the treatment of choice. If you are trying to decide between a lumpectomy and radiation or mastectomy, it is important to understand the implications, recovery and long-term side effects of both before you make your decision.