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Prophylactic Mastectomy

What is Prophylactic Mastectomy?

Prophylactic mastectomy (also called preventive mastectomy) is the surgical removal of both breasts to help prevent breast cancer. Prophylactic mastectomy is a controversial procedure among members of the medical community. Many physicians do not believe that surgically removing a woman’s breast is appropriate unless it is performed as a treatment for breast cancer. However, based on recent scientific findings that show prophylactic mastectomy to be effective at preventing breast cancer, other physicians believe that certain individuals at especially high risk of breast cancer who are very worried about developing the disease may benefit from having prophylactic mastectomy. According to a statement from the American Cancer Society Board of Directors, "only very strong clinical and/or pathological indications warrant doing this type of "preventive operation."

A woman's decision to have prophylactic mastectomy should be made carefully with physicians and counselors and should be a decision comfortable to the woman. Women considering the procedure should discuss their decision with close family members, friends, or other women who have previously undergone prophylactic mastectomy, if possible.

During a prophylactic mastectomy, the surgeon removes the entire breast, with its skin and nipple. This is called a simple or total mastectomy (see the mastectomy section for additional information). Because the operation is not being performed for cancer treatment, lymph node removal is not necessary. Prophylactic mastectomy can usually followed by immediate or delayed breast reconstruction.

Who is a Candidate for Prophylactic Mastectomy?

Women should be aware that prophylactic mastectomy is an irreversible procedure and the decision to have the surgery should be made very carefully. Women considering the procedure should consult several physicians (preferably breast cancer specialists) who can provide specific information on the woman's individual risk of breast cancer. Physicians should also provide information on side effects, complications, and options for breast reconstruction (and the associated risks of reconstruction). It is also recommended that women who are considering prophylactic mastectomy discuss the procedure with a professional counselor who has experience dealing with patients who are considering this preventive option.

Women who are at high risk of breast cancer who may wish to consider prophylactic mastectomy after weighing other preventive options for breast cancer include:

  • Those with a strong family history of breast cancer (especially if the breast cancer was diagnosed among several first-degree relatives, mother or sisters, before age 50)
  • Those who have tested positive for the BRCA1 or BRCA2 gene mutations
  • Those who have a personal history of breast cancer and are at high risk for a recurrence
  • In some cases, those who have been diagnosed with lobular carcinoma in situ (a marker for increased breast cancer risk)
  • Less commonly, those at risk of breast cancer who also have breast microcalcifications (tiny calcium deposits) or who have very dense breast tissue which makes it difficult to detect breast cancer with imaging exams, such as mammography. 

Also, some women who have had multiple breast biopsies revealing non-cancerous conditions, which have caused scar tissue and other complications that may make it difficult to detect breast cancer in the future, may wish to consider prophylactic mastectomy.

According to a past statement from the American Cancer Society Board of Directors, "only very strong clinical and/or pathological indications warrant doing this type of "preventive operation."

Is Prophylactic Mastectomy Effective?

Since most of the breast tissue is removed during prophylactic mastectomy, the chances that a woman will develop breast cancer are significantly reduced. A study conducted by Lynn C. Hartman, MD of the Mayo Clinic in Rochester, Minnesota and her colleagues found that prophylactic mastectomy can reduce the likelihood that a woman will develop breast cancer by at least 90%.  (1)  Similarly, a study published in the Journal of the American Medical Association in September 2010, found that among 247 women who were at genetically high risk of developing breast cancer and who underwent preventive mastectomies, none developed breast cancer during the three years of follow up after the surgeries, compared to 7% of more than 1300 women in the study who opted not to have their breasts removed. (2)

However, having a prophylactic mastectomy does not guarantee that a woman will never develop breast cancer. It is impossible for surgeons to remove every breast cell during mastectomy, and therefore, some breast tissue cells will remain. According to Dr. Hartman, if only three cells are left, cancer could develop from those three cells. In the Mayo Clinic study, three of the 214 women who had prophylactic mastectomy developed breast cancer within 14 years of having the surgery.

While prophylactic mastectomy reduces the chances of developing breast cancer, some women identified to be at high-risk of breast cancer will never develop the disease, and thus, prophylactic mastectomy is not necessary for these women. However, in another study published in the Journal of the American Medical Association found that the majority of women who opt for prophylactic mastectomy to lower their risk of breast cancer are satisfied with their decision.(3)

In that study, Marlene H. Frost, RN, PhD of the Mayo Clinic and her colleagues studied 572 women with a family history of breast cancer who had prophylactic mastectomy between 1960 and 1993. The researchers found that 70% of the women were satisfied with the procedure, 11% were neutral, and 19% were dissatisfied. The majority of women also reported no change or favorable effects on their emotional stability, level of stress, self-esteem, sexual relationships, feelings of femininity, and satisfaction with their body appearance.

What are Alternatives to Prophylactic Mastectomy to Help Lower Breast Cancer Risk?

For women at high risk of breast cancer, there are a number of options available besides prophylactic mastectomy to reduce the chances of developing the disease.

Alternative Options for Women at High Risk of Breast Cancer
  • Frequent monitoring by a physician
  • Taking tamoxifen
  • Enrolling in the STAR clinical trial

Frequent monitoring: Many women at high risk for breast cancer are closely monitored by physicians with frequent clinical breast exams and mammograms (at an interval determined by the physician). All women should also practice monthly breast self-exams and see a physician immediately if they notice any changes or abnormalities. The earlier breast cancer is detected, the greater the chances for successful treatment and survival.

Guidelines for all women: Because breast cancer affects approximately 1 in 8 women, all women should follow recommended screening guidelines to help detect breast cancer in its earliest stages, when the chances for survival are the greatest. The American Cancer Society, the American College of Radiology, the American College of Surgeons and the American Medical Association recommend the following:

  • All women between 20 and 39 years of age should practice monthly breast self-exams and have a physician performed clinical breast exam at least every three years.
  • All women 40 years of age and older should have annual screening mammograms, practice monthly breast self-exams, and have yearly clinical breast exams.
  • Women with a family history of breast cancer or those who test positive for the BRCA1 or BRCA2 gene mutations may want to talk to their physicians about beginning annual screening mammograms earlier than age 40, as early as age 25 in some cases.

Tamoxifen: In 1998, the U.S. Food and Drug Administration (FDA) approved the use of the drug tamoxifen for women who are at high risk of developing breast cancer. In a National Adjuvant Breast and Bowel Project (NSABP) study of 13,388 women at high risk of breast cancer (determined by family history, etc.), researchers found that the use of tamoxifen for a period of five years reduced the incidence of breast cancer by 49%. Most physicians who prescribe tamoxifen to help prevent breast cancer recommend that women take it for a period of five years. Tamoxifen has been shown to cause a number of side effects in some women, most commonly hot flashes, and poses a slight increase in the risk for endometrial cancer (cancer of the lining of the uterus), blood clotting, and other conditions. Click here to learn more about tamoxifen.

 

Additional Resources and References

Updated: September 2010