Impact of an In-visit Decision Aid on Patient Knowledge About Contralateral Prophylactic Mastectomy: A Pilot Study

Background: Studies have reported that breast cancer patients have limited understanding about the oncologic outcomes following contralateral prophylactic mastectomy (CPM). We hypothesized that an in-visit decision aid (DA) would be associated with higher patient knowledge about the anticipated short and long term outcomes of CPM.

Methods: We piloted a DA which used the SCOPED: (Situation, Choices, Objectives, People, Evaluation and Decision) framework. Knowledge, dichotomized as "low" (≤3 correct) versus "high" (≥4 correct), was assessed immediately after the visit by a 5 item survey. There were 97 DA patients (response rate 62.2 %) and 114 usual care (UC) patients (response rate 71.3 %).

Results: Patient demographic factors were similar between the two groups. Twenty-one (21.7 %) patients in the DA group underwent CPM compared with 18 (15.8 %) in the UC group (p = 0.22). Mean and median knowledge levels were significantly higher in the DA group compared with the UC group for patients of all ages, tumor stage, race, family history, anxiety levels, worry about CBC, and surgery type. Eighty-six (78.9 %) of UC versus 35 (37.9 %) DA patients had low knowledge. Of patients who underwent CPM, 15 (83.3 %) in the UC cohort versus 5 (25.0 %) of DA patients had "low" knowledge.

Conclusions: Knowledge was higher in the DA group. The UC group had approximately three times the number of patients of the DA group who were at risk for making a poorly informed decision to have CPM. Future studies should assess the impact of increased knowledge on overall CPM rates.