Bilateral Prophylactic Mastectomy / Screening Mammography for High-Risk Women

Bilateral Prophylactic Mastectomy Rarely More Cost-Effective Than Screening Mammography for High-Risk Women

By The ASCO Post
Posted: 5/1/2015 12:00:35 PM
Last Updated: 5/1/2015 12:00:35 PM

Key Points:
•Bilateral prophylactic mastectomy becomes more cost-effective than screening mammography alone at a lifetime breast cancer risk of 50% and should be reserved for women with a very high risk of breast cancer.
•Annual screening with a combination of mammography and magnetic resonance imaging (MRI) was never more cost-effective than bilateral prophylactic mastectomy at any risk level.
•Additional screening modalities for use in high-risk women with a lower cost than MRI are needed.
Annual screening mammography is significantly more cost-effective than bilateral prophylactic mastectomy in managing the care of most women at high risk for breast cancer. Women with a known BRCA gene mutation, which carries an exceptionally high risk, are a notable exception.

These were the findings of a study presented at the American Society of Breast Surgeons Annual Meeting by lead researcher Brandy Edwards, MD, of the University of Virginia. The study found that a woman’s projected lifetime breast cancer risk must reach approximately 50% for bilateral prophylactic mastectomy to deliver cost benefits for the number of lives saved. The typical woman’s risk of breast cancer is 12% averaged over the course of her lifetime. Factors such as a family breast cancer history, certain benign breast conditions, and hormone use place a woman at elevated risk.

“Cost-effectiveness analysis is an increasingly important tool to aid in clinical decision-making, particularly in today’s age of health-care reform,” said Dr. Edwards. “Previous studies have made the economic case for prophylactic procedures in women with BRCA mutations or in contralateral mastectomies for patients with cancer in the other breast. This is the first study to demonstrate that a woman without breast cancer or a known genetic mutation must have substantial risk to cost-justify prophylactic surgery.”

Study Details

The study relied on a Markov model, a validated statistical methodology utilized in numerous scientific studies to simulate effects that change over time. Model parameters included costs, sensitivity and specificity of screening modalities, and mortality rates. The study assumed a 90% breast cancer risk reduction with bilateral prophylactic mastectomy. It focused on patients beginning at age 30 and assumed that full lifetime risk would be met at age 80. Sensitivity analyses were conducted to assess how changes in the model parameters affected the results.

“Based on information in the published literature, we also adjusted the model to account for expected patient preferences for bilateral prophylactic mastectomy compared to screening,” noted Dr. Edwards. “These numbers also demonstrate that bilateral prophylactic mastectomy should primarily be considered in women with very high risk. When accounting for these patient preferences, an approximate 50% lifetime risk still emerged as the point where bilateral prophylactic mastectomy would be considered a cost-effective alternative to screening. However, while cost-effectiveness studies are a valuable tool to compare interventions, the results should not be the sole criterion for deciding whether or not a certain treatment should be used or covered by health insurance. At the end of the day, this is a highly personal decision that must be made on a patient-by-patient basis.”

Affordable Screening Technologies Needed

The study also found that annual screening with a combination of mammography and magnetic resonance imaging based on Medicare reimbursement rates was never more cost-effective than bilateral prophylactic mastectomy at any risk level and that the additional survival benefit associated with combined screening is very small when compared with mammography screening alone.

“Today, technology brings significant breakthroughs in the diagnosis and treatment of disease at a rapid pace,” concluded Dr. Edwards. “But, physicians have to examine costs and benefits because health care is not an infinite resource. Clearly there is a need for additional affordable screening technologies for women at high risk for breast cancer. While prophylactic mastectomy is appropriate for some women, it can carry steep costs, both economically and in quality of life, because prophylactic surgery isn’t without risk.”