Every woman diagnosed with early-stage breast cancer faces a decision about what type of surgery to have. Together with her doctors, she will have to choose between breast-conserving surgery (BCS), also called lumpectomy, and mastectomy. BCS preserves the breast, removing the tumor and a rim of surrounding tissue, whereas mastectomy removes the entire breast. Patients with early-stage disease (with the main tumor less than 4 cm across and 3 or fewer lymph nodes positive for cancer) are usually eligible for either BCS or mastectomy. More importantly, lumpectomy followed by radiation is just as effective as mastectomy. One would think most women would choose BCS as a less invasive (and breast-conserving!) procedure, but the numbers tell a different story.
Mastectomy used to be the routine surgical treatment for breast cancer, including early-stage cancer, up until the mid-1980s. In 1990, the National Institutes of Health (NIH) Consensus Development Conference on Treatment of Early-Stage Breast Cancer recommended BCS for the majority of women with stage I or II breast cancer. By the mid-1990s, BCS had become the predominant type of surgery for early breast cancer. An analysis performed in 1999 estimated that from 1985 through 1989, approximately 35% of women with stage I cancer underwent BCS, and in the next 5 years (1990-1995) the percentage jumped to 60%. For women with stage II breast cancer, the percentage rose from 19% to 39%.
Why did this dramatic shift take place? The reason is that multiple clinical studies showed that survival after either of two surgeries is very much the same, especially when BCS is followed by radiation treatment. Published in 2002, a 20-year follow-up of women who had either BCS or mastectomy convincingly showed that overall survival after lumpectomy with radiation was equivalent to overall survival after mastectomy. Many studies have followed, reaching the same conclusion. The Susan G. Komen Foundation has compiled data from numerous trials comparing the two procedures, which clearly show no difference in overall survival after many years of follow-up.
With the recommendation of BCS in 1990, the medical community was happy to be able to offer women both a less invasive and traumatic surgical option, and women, it seems, were happy to have this choice. But fast-forward just about 10 years, and you will see that the trend was not there to stay. The numbers tell it all: a 2001 study of over 16,000 women with stage I and II breast cancer revealed that fewer women (42.6%) had chosen BCS, preferring mastectomy.
Bilateral mastectomy for unilateral cancer (removal of both breasts when only one has a tumor) is also on the rise. A 2014 analysis of close to 190,000 early-stage breast cancer cases revealed that, in California, the percent of women choosing bilateral mastectomy increased from 2.0% in 1998 to 12.3% in 2011. The same study also showed that removal of just one breast carried a somewhat higher risk of overall mortality than lumpectomy—a finding that certainly doesn’t encourage the use of mastectomy.
And a recent JAMA Surgery analysis of 1.2 million women calculated that, between 2003 and 2011, the number of women who chose mastectomy increased by 34%. Surprisingly, this increase was more pronounced in women whose cancers were the smallest and did not involve their lymph nodes. Moreover, the rate of bilateral mastectomy increased even more dramatically, from 1.9% in 1998 to 11.2% in 2011, similar to the 2014 study mentioned above.
The question is, of course, why? Why choose an intrusive surgery versus a relatively easy one if both produce the same rate of cure? An obvious answer would be that women are not well informed when they make their choices. However, a 2009 study in the Journal of Clinical Oncology analyzed decision-making in 125 women who were eligible for either procedure. The title of this study was, tellingly: “Can Women with Early-Stage Breast Cancer Make an Informed Decision for Mastectomy?” And the answer was no. These 125 women were exceptionally well informed about the risks and had received extensive counseling from medical teams. Ninety-eight percent of them showed they understood that the survival benefits are the same for both procedures; nevertheless, 35% chose mastectomy.
To understand why, let’s consider the general pros and cons of mastectomy. There are two main forces that influence a woman’s decision to have BCS versus mastectomy: the desire to keep one’s breast versus the fear that cancer will come back in the same breast. But these are not the only considerations. Other factors are at play include the following:
In favor of mastectomy:
- Lumpectomy is often followed by radiation, which is time-consuming and could cause scarring. However, this concern is partially offset by the option of hypofractionated radiotherapy (higher doses of radiation given over a shorter time).
- During breast conserving surgery, the surgeon might find that the tumor is more invasive than initially thought, and it is difficult to obtain clear margins. In this case, the surgeon might switch mid-operation to mastectomy.
- If the tumor returns after lumpectomy and radiation, a repeat radiation treatment is not an option, and mastectomy will most likely be performed. In this case, the previous radiation treatment might also complicate breast reconstruction.
- After mastectomy (especially bilateral, in which both breasts are removed), there is no need to undergo mammography examinations and experience the anxiety inevitably associated with them.
- BCS does not require hospitalization, and recovery after BCS goes much faster. Mastectomy is a far more serious procedure that sometimes results in complications, such as lymphedema (swelling of the arm).
- Drainage tubes are not usually placed after BCS, but they are used after mastectomy. Drainage tubes may be used for a few days or weeks after surgery to help fluid buildup at the surgical site exit the body.
- Pain and discomfort after BCS are much less, and breast reconstruction is usually unnecessary.
- Having a mastectomy does not mean that a woman can forego chemotherapy after surgery. This decision of whether to have chemotherapy is based on the tumor characteristics, not on the type of surgery, and chemotherapy can be given after either BCS or mastectomy.
- Mastectomy, especially when performed with immediate reconstruction, results in a very high (30%-50%) risk of complications such as infection, poor healing, or problems with implants.
- After lumpectomy, a woman can change her mind and undergo mastectomy, but mastectomy is permanent.
- Breast reconstruction is not always possible immediately after mastectomy (during the same surgery session). If breast reconstruction is not performed right after mastectomy, it means another surgery must be scheduled.
It is clear that the list of ‘cons’ for mastectomy is longer. It is also likely that some very personal (and likely emotional) considerations go into each patient’s decision. In the end, when all odds are equal, the decision belongs to the patient.
It seems appropriate to end this essay with the conclusion of the 2009 study mentioned above:
“Although conventional wisdom may view BCS as the preferred treatment, a notable proportion of well-informed women choose mastectomy. …subjective preferences underlie decision making. The systematic use of a decision aid before the surgical consultation may help women make informed, values-based decisions, while clearly reducing decisional conflict.”
http://www.nejm.org/doi/full/10.1056/NEJMoa022152 NEJM 2002
http://jco.ascopubs.org/content/19/8/2254.abstract?ijkey=aa5d96bdb3a2b65f2145c6197013a546e868f7eb&keytype2=tf_ipsecsha JCO 2001
http://www.ncbi.nlm.nih.gov/pubmed/25182099 JAMA 2014
http://jco.ascopubs.org/content/27/4/519.long#ref-6 JCO 2009
JAMA S 2015