Guidelines for Guidelines: An Assessment of the American Society of Breast Surgeons Contralateral Prophylactic Mastectomy Consensus Statement.

Abstract

The rates of contralateral prophylactic mastectomy (CPM) have markedly increased in the US over the past 2 decades. These trends have been observed in all patient age groups, cancer stages, races, and in all geographic regions of the US. In the most recently published analyses from the Surveillance Epidemiology and End Results database, the CPM rates were still increasing with no plateau. Most patients who undergo CPM do not have strong genetic or familial risk factors for developing contralateral breast cancer. Recent survey studies have demonstrated that breast cancer patients substantially overestimate the risk of contralateral breast cancer and have unrealistic outcomes from CPM. Moreover, in a survey study among active members of the American Society of Breast Surgeons (ASBrS), Yao et al. concluded that 39.2 % of respondents had a ‘low level of knowledge about CPM’. Given the gaps in knowledge among both patients and surgeons, the publication of the ASBrS consensus statement is timely. In 1993, the Society of Surgical Oncology (SSO) developed a position statement on the use of CPM, which was most recently edited and updated in March 2007. Since the last revision of this position statement, many important studies have been published evaluating the risks of contralateral breast cancer, outcomes after CPM, and patients’ perceptions and preferences. The ASBrS consensus statement appropriately incorporates most of this relevant recent research. In the strongest language to date, the consensus statement recommends that CPM should be ‘discouraged’ for patients with an average risk of contralateral breast cancer. This population of patients represents the vast majority of women who undergo CPM in the US. The statement further concludes that ‘CPM should be considered’ for selected groups at significant risk of contralateral breast cancer (including carriers of BRCA 1 or 2 deleterious mutations). Furthermore, ‘CPM can be considered’ for selected groups at lower risk of contralateral breast cancer (including other gene mutation carriers). Additionally, ‘CPM may be considered’ for non-oncologic reasons (including limiting contralateral breast surveillance). Finally, ‘CPM should be discouraged’ for patients with advanced primary-stage breast cancer and patients who are in overall poor health or at very high risk of associated complications. In recent years, there has been a rapid proliferation in the number and scope of published clinical practice guidelines and consensus statements. To address the substantial variation in the clinical guideline development processes, the Institute of Medicine (IOM) published eight standards in ‘Clinical Practice Guidelines We Can Trust’ in 2011. Although there are subtle differences between consensus statements and clinical practice guidelines, both should be transparent, multidisciplinary, evidence-based, and intended to provide guidance to clinicians and patients. The ASBrS CPM consensus statement adheres to some, but not all, of the IOM standards. For example, the IOM recommends that the clinical guideline development group be multidisciplinary, balanced, and include current/former Society of Surgical Oncology 2016