Single mastectomy is a more cost-effective treatment for nonhereditary cancer in one breast than removing both breasts

U.S. women with unilateral breast cancer are increasingly choosing CPM, which is the surgical removal of the healthy breast along with the cancerous one to prevent the risk of breast cancer occurring in the healthy breast. One national study reported that the CPM rate increased from 1.9 percent in 1998 to 10.2 percent in 2011.¹ However, there is no strong evidence that prophylactic mastectomy improves survival for women with sporadic breast cancer,² and a double mastectomy poses nearly double the risk of postoperative complications.³ On the other hand, most women who have both breasts removed do not need annual screening mammograms.⁴

Researchers, led by Nicolas Ajkay, MD, FACS, assistant professor of surgery at the University of Louisville School of Medicine in Louisville, Ky., conducted this study to help patients and their surgeons in the decision-making process about which operation to choose.

Using a decision tree/probabilities model,⁵ the researchers compared the estimated long-term costs of each operation, follow-up care, and the patient's health-related quality of life after the operation, assuming both ideal and poor outcomes.

"Even under worst-case scenarios, we found that costs and quality of life were superior with unilateral mastectomy," Dr. Ajkay said. "With our study results, I can counsel patients that they may incur a higher cost over their lifetime with a lower quality of life for several months if they choose CPM.'"

Single mastectomy plus 20 years of routine mammograms on the remaining breast costs, on average, $5,052 less than CPM ($13,525 versus $18,577), the research team reported. In estimating costs, the investigators took into account physician and imaging fees, hospitalization, other cancer treatments, and cost-of-living expenses, with all data from 2014 or adjusted to 2014 costs.

From the recent medical literature, the researchers derived the probabilities of ideal outcomes and poor outcomes over 10 years, both with and without breast reconstruction. Poor outcomes included wound complications requiring another operation and, in cases of single mastectomy, the development of breast cancer in the opposite breast five and 10 years later.

To estimate patients' quality of life, Dr. Ajkay and colleagues used the health-related quality of life measure of a quality-adjusted life year (QALY),⁶ in which a year in perfect health has a rating of 1.0 QALY. After 20 years of follow-up care, women who underwent unilateral mastectomy had a net gain of 0.21 QALYs (14.75 versus 14.54 QALYs), which Dr. Ajkay said equates to approximately three months of improved health and quality of life.

For a woman who chooses CPM, a QALY loss of 0.21, according to Dr. Ajkay, could mean "about three months of struggling with surgical complications of reconstruction, lost work productivity, and significant emotional hardship."

Because women who undergo unilateral mastectomy have a much lower rate of breast reconstruction than those who opt for CPM, the researchers also calculated probabilities assuming that all women undergoing single mastectomy also had reconstruction. In that scenario, the cost and QALY were still better than for CPM, according to the study abstract. For an ideal outcome with reconstruction, unilateral mastectomy and screening mammograms reportedly cost $19,158, or $1,234 less than the $20,392 cost of CPM, and the QALY was 0.20 better than that with CPM.

Dr. Ajkay cautioned however that their study results do not apply to women with a familial or genetic risk of breast cancer, who were excluded from participating in this study. He said, "In most clinicians' view, these patients do benefit from CPM."