Many studies done in the 1970s showed that lumpectomy plus radiation to treat women diagnosed with early-stage breast cancer offered the same survival rates as mastectomy. Based on these studies, the U.S. National Institutes of Health released a statement in 1990 saying that lumpectomy plus radiation was preferred over mastectomy to treat early-stage breast cancer.
Still, because younger women in general have a longer life expectancy than older women, researchers have wondered if they had a higher risk of recurrence (the cancer coming back) after lumpectomy and so would benefit more from mastectomy.
A study suggests that younger women diagnosed with early-stage disease get more benefits from mastectomy than lumpectomy plus radiation, while older women get about the same benefits from either type of surgery.
The research was presented on April 30, 2016 at the European Society for Radiotherapy & Oncology Annual Meeting. Read the abstract of “Long-term age dependent failure pattern after BCT vs. mastectomy in low-risk breast cancer patients."
The study followed 1,076 Danish women diagnosed with early-stage breast cancer between 1989 and 1998 for 20 years. The cancers were considered to have a low risk of recurrence because they were smaller than 5 centimeters and had not spread to the lymph nodes.
- 364 women had lumpectomy and radiation therapy
- 712 had mastectomy
None of the women received chemotherapy after surgery.
After 20 years, overall local recurrence rates (the cancer coming back in the same area of the breast where it was originally diagnosed) were:
- 18% for women who had lumpectomy (66 women)
- 6.7% for women who had mastectomy (55 women)
When the researchers looked at the women by age groups, there were some striking differences in local recurrence rates:
- women 45 or younger who had lumpectomy had a 25% recurrence rate, compared to 11% for women older than 45 who had lumpectomy
- women 45 or younger who had mastectomy had a 13% recurrence rate, compared to 3% for women older than 45 who had mastectomy
So women 45 and younger diagnosed with early-stage breast cancer had a higher risk of recurrence compared to older women, no matter which surgery they had.
Younger women who had lumpectomy were 60% to 70% more likely to die from breast cancer 20 years after diagnosis compared to women older than 45 who had lumpectomy. Also, younger women who had a local recurrence were twice as likely to have a distant metastasis -- the cancer coming back in a part of the body away from the breast.
Among women who had a mastectomy, most local recurrences happened in the first 5 years after diagnosis for older women and in the first 10 years for younger women.
"Among the patients younger than 45, local recurrence was associated with distant metastasis, and young patients treated with breast-conserving therapy [lumpectomy] had an increased risk of death during the 20 years, either from their disease or from other causes, compared to those who underwent mastectomy," said Tinne Laurberg, M.D., of Aarhus University Hospital in Denmark, who presented the study. "When future treatment guidelines for young, lymph-node negative patients are refined, the possibility of the negative impact of breast-conserving therapy on survival in these young women should be taken into account.
"We found that among patients older than 45 years receiving BCT, local recurrence was not associated with distant metastasis and the 20-year mortality was not different between BCT and mastectomy," she continued. "These findings are in line with long-term data reported from several randomized trials, confirming that it is safe to offer older, lymph-node negative patients breast conserving therapy and adjuvant radiation therapy."
The researchers said that one limitation of the study was that the women were diagnosed and treated from 1989 to 1998, when cancer treatment wasn’t as effective as it is today. The study also was a population-based study, which means the researchers used information collected before the study was planned. It also means that the women weren’t randomly assigned to get lumpectomy plus radiation or mastectomy. So the women may have had other health problems that might have affected the type of surgery they had. These other health conditions also may have affected their survival. Population-based studies aren’t considered as good as randomized clinical studies.
The study also didn’t look at:
- HER2 status of the cancer
- the distance to the nearest radiation treatment center
- whether the women had earlier radiation to the chest wall
- other health conditions the women may have had (diabetes, circulatory problems, or a bleeding disorder, for example)
All of the above factors can affect the lumpectomy vs. mastectomy decision-making process.
Still, the study has 20 years of follow-up information, which makes the information important. Most studies have only 5 to 10 years of follow-up.
If you’ve been diagnosed with early-stage breast cancer, you and your doctor will talk about a surgical approach that makes the most sense for you and your unique situation. You will take into account a number of factors, including:
- your preferences
- your age
- any other health problems you have
- ALL the characteristics of the cancer
- how close you are to treatment facilities
For more information on factors to consider when deciding on a type of surgery for early-stage breast cancer, visit the Breastcancer.org Mastectomy vs. Lumpectomy page.