Project Summary/Abstract In the United States, young women with early-stage breast cancer are increasingly choosing to have their unaffected breast removed, a procedure known as contralateral prophylactic mastectomy (CPM) or bilateral (“double”) mastectomy. The clinical benefits of CPM (e.g., no survival benefit) are minimal and there are documented harms, including an increased risk of surgical complications and the potential for negative quality of life sequelae. Additionally, the American Society of Breast Surgeons and Choosing Wisely guidelines recommend against the routine use of CPM among average risk women with unilateral breast cancer. Prior research has suggested that the risks and benefits of breast cancer surgery are not being optimally communicated and that some women have inaccurate perceptions about breast cancer risks that are likely impacting their choice of surgery. Life-stage specific factors (e.g., breastfeeding, body image) can make surgical decisions particularly complex for young women and young women report high levels of decisional conflict regarding the surgical decision. To optimally support young women making decisions about breast cancer surgery, we developed CONSYDER, a web-based decision support tool tailored to the unique concerns of young patients. In our pilot study, all women who used CONSYDER found it helped them understand the pros and cons of surgery and clarify their values around this highly preference sensitive decision. CONSYDER is innovative in its approach to decision support in that integrates supportive care resources to help manage stress and anxiety around diagnosis as part of the decision tool. These resources were valued by patients, demonstrating the acceptability of this approach that acknowledges their psychosocial needs. We are now proposing a pragmatic, stepped-wedge, multicenter trial that incorporates a Type II hybrid effectiveness-implementation design. We will test the effectiveness of CONSYDER in reducing decisional conflict before surgery among 800 young women seeing a breast cancer surgeon at Yale Smilow Cancer Center, Weill Cornell Medicine, Dana-Farber Cancer Institute, and Duke Cancer Institute. Concurrently, we will use a mixed-methods approach, including surveys and semi-structured interviews with patients and providers, to evaluate the value and implementation of CONSYDER. Implementation outcomes will include feasibility of delivery, adoption and fidelity across sites, uptake of key features, and sustainability. Our pragmatic study will test the effectiveness and implementation of an intervention designed to promote shared decision-making and reduce decisional conflict in young women with breast cancer. We expect findings from the proposed study not only to demonstrate the effectiveness of this novel intervention but also to inform the optimal delivery and broader dissemination of CONSYDER, enabling patient-centered support for the highest quality preference-sensitive decisions for young women with breast cancer facing surgery.

Project Narrative Rates of contralateral prophylactic mastectomy (CPM) have been increasing in the United States among young women with breast cancer. The proposed pragmatic study will evaluate the effectiveness of CONSYDER, a decision support tool for young women making breast cancer surgical decisions, in improving decision quality, thereby potentially reducing CPM, while also evaluating CONSYDER’s implementation across 4 different health systems. We expect findings to not only demonstrate the effectiveness of this intervention but also to inform the optimal delivery of CONSYDER, enabling broader dissemination of this intervention in the future.