Purpose: The purpose of this study was to measure the degree to which informed women chose mastectomy, and to reveal their reasons for this choice.
Patients and methods: This was a prospective cohort study of patients radiographically and pathologically eligible for either mastectomy or breast-conserving surgery (BCS; n = 125). Participants completed questionnaires at three time points: baseline, after viewing a decision aid, and after a surgical consultation. Questionnaires assessed clinical history, preference for participation in decision making, information comprehension, values, decisional conflict, and preferred treatment.
Results: Of 125 participants, 44 (35%) chose mastectomy. Most understood that BCS and mastectomy offer an equivalent survival benefit (98%) and that BCS has a slightly higher local recurrence risk (63%); most accurately identified the magnitude of ipsilateral local recurrence risk (91%). Values assigned to three treatment attributes/outcomes ("remove breast for peace of mind," "avoid radiation," and "keep breast") clearly discriminated between patients choosing mastectomy or BCS. High decisional conflict scores improved after both the decision aid and surgical consultation.
Conclusion: Although conventional wisdom may view BCS as the preferred treatment, a notable proportion of well informed women choose mastectomy. Whereas prior studies have linked objective factors to treatment choice, this study reveals subjective preferences that underlie decision making. The systematic use of a decision aid before the surgical consultation may help women make informed, values-based decisions, while clearly reducing decisional conflict.