AHRQ Data: Mastectomies Increased 36 Percent From 2005 to 2013

While breast cancer rates remained constant between 2005 and 2013, the rate of women undergoing mastectomies increased 36 percent, including a more than tripling of double mastectomies, according to new AHRQ data. Both single and double mastectomies are increasingly performed as outpatient procedures, and the overall proportion of mastectomies performed in hospital-based ambulatory surgery settings reached 45 percent in 2013. “This brief highlights changing patterns of care for breast cancer and the need for further evidence about the effects of choices women are making on their health, well-being and safety,” said AHRQ Director Richard Kronick, Ph.D. “More women are opting for mastectomies, particularly preventive double mastectomies, and more of those surgeries are being done as outpatient procedures.” Choosing a mastectomy rather than breast-conserving treatment, or electing to undergo a double mastectomy rather than single mastectomy, may be based on physician advice, fear of cancer recurrence or desire for cosmetic symmetry. The choice may also be influenced by a family history of breast cancer, or mutations in the BRCA1 andBRCA2 gene. AHRQ’s analysis shows a twofold increase in double mastectomies for women who don’t have cancer, although the number of women making this choice remains low. Find more data on the topic in “Trends in Bilateral and Unilateral Mastectomies in Hospital Inpatient and Ambulatory Settings, 2005-2013,” a statistical brief from AHRQ’s Healthcare Cost and Utilization Project. Click here for an infographic and here for a blog post from AHRQ’s Claudia Steiner, M.D., M.P.H., about the findings.

Highlights

Between 2005 and 2013, the rate of hospital-based bilateral overall rate of mastectomy increased 36 percent, from 66 to 90 per 100,000 adult woment. The rate of hospital-based bilateral mastectomies (inpatient and outpatient combined) more than tripled, from 9.1 to 29.7 per 100,000 adult women, whereas the rate of unilateral mastectomies remained relatively stable at around 60 per 100,000 women.

Women who had a bilateral mastectomy in 2013 were about 10 years younger than those who had a unilateral mastectomy.

From 2005 to 2013, the rate of bilateral outpatient mastectomies increased more than fivefold and the inpatient rate nearly tripled. The rate of unilateral mastectomies nearly doubled in the outpatient setting but decreased 28 percent in the inpatient setting. By 2013, nearly half of all matectomies were performed outpatient.

Regardless of hospital setting, between 2005 and 2013, bilateral mastectomies with cancer more than tripled and bilateral mastectomies without cancer more than doubled. The rate of unilateral mastectomies without cancer also increased (by 38 percent), but the rate of unilateral mastectomies with cancer remained stable.

The proportion of hospital-based mastectomies shifted away from unilateral mastectomies with breast cancer and toward bilateral mastectomies, with and without breast cancer. By 2013, more than one in four hospital-based mastectomies were bilateral with cancer.

Trends in Bilateral and Unilateral Mastectomies in Hospital Inpatient and Ambulatory Settings, 2005-2013

Claudia A. Steiner, M.D., M.P.H., Audrey J. Weiss, Ph.D., Marguerite L. Barrett, M.S., Kathryn R. Fingar, Ph.D., M.P.H., and P. Hannah Davis, M.S.

Introduction

Mastectomy (surgical removal of the breast) is a common procedure used in the treatment of breast cancer. Although 97-99 percent of breast cancers occur in only one breast,¹ some women choose also to remove the healthy breast—a contralateral prophylactic mastectomy (CPM). Reasons that women elect to undergo CPM include physician advice, fear of a subsequent breast cancer diagnosis, desire for cosmetic symmetry, family history of breast cancer, and genetic susceptibility to breast cancer due to mutations in the BRCA1 and BRCA2genes.^2,3 Some women, such as those with a genetic predisposition to breast cancer, may choose to have prophylactic bilateral mastectomy without occurrence of cancer in either breast.

Research indicates that the proportion of women choosing mastectomy over breast-conserving surgery, such as lumpectomy, increased from 1998 to 2011.⁴ Much of this increase is attributed to an increase in bilateral mastectomy involving early-stage cancer in one breast and CPM of the other breast.⁵ Indeed, among women undergoing treatment for early-stage breast cancer, the percentage of those having CPM increased more than fivefold between 1998 and 2011 (from 1.9 to 11.2 percent).⁶ During this approximate time period, from 2002 through 2012, the incidence of breast cancer overall remained stable at around 130 per 100,000 women.⁷

At the same time that mastectomies have been increasing, research suggests that mastectomy procedures are shifting to an outpatient setting.⁸ In 2003, approximately 22 percent of mastectomies across 17 States were performed in a hospital outpatient setting.⁹ By 2012, about 42 percent of mastectomies were done outpatient.¹⁰

This Healthcare Cost and Utilization Project (HCUP) Statistical Brief presents data on bilateral and unilateral mastectomies among adult women in two hospital settings: hospital inpatient and hospital-based ambulatory surgery. The analysis is limited to hospitals within 13 States—representing more than one-fourth of the U.S. population—for which bilateral versus unilateral mastectomies could be identified in both the inpatient and ambulatory surgery settings. Bilateral mastectomies with a cancer diagnosis are likely unilateral mastectomies for cancer with a CPM. Bilateral mastectomies without a cancer diagnosis are likely prophylactic bilateral mastectomies. Unilateral mastectomies without a cancer diagnosis are likely CPMs following a prior unilateral mastectomy with cancer in the other breast.

In this Statistical Brief we provide an overview of characteristics of mastectomies by hospital setting (inpatient and ambulatory surgery) in 2013. We present trends in the overall rates of bilateral and unilateral mastectomies and by hospital setting from 2005 through 2013. The cumulative percentage change over the 9-year time period in the rate of mastectomies based on hospital setting and presence of breast cancer also is provided. Finally, the proportion of all hospital-based mastectomies by type of mastectomy and presence of breast cancer is presented. All differences noted in the text differ by at least 10 percent.

Findings

Characteristics of hospitalizations for mastectomy, 2013
Table 1 presents characteristics of bilateral and unilateral mastectomies performed in the hospital inpatient setting compared with the hospital-based ambulatory surgery setting in 2013.