The Unique Mental Impacts of Breast-Conserving Surgery and Mastectomy According to a Multi-Centered Cross Sectional Survey Conducted in Japan

Background: Improving health-related quality of life (HRQOL) has become a fundamental goal of breast cancer management. This study aimed to examine the differences between the QOL outcomes of breast-conserving surgery (BCS) and mastectomy. We also established structural equation models for BCS and mastectomy to elucidate their unique effects on QOL.Methods: Between July 2019 and November 2019, 254 patients, who were scheduled to visit one of four clinics, were recruited for this study. We evaluated HRQOL using various questionnaires, such as the BREAST-Q, EQ-5D-5L, and Hospital Anxiety and Depression Scale (HADS). The relationships among the examined clinical indicators were evaluated using structural equation modeling (SEM). Results: The QOL scores of the BCS group were better than those of the mastectomy group (0.85±0.129 vs. 0.81±0.12, P=0.020). Also, anxiety (2.94±2.95 vs. 3.81±3.08, P=0.025) and depression (2.55±2.77 vs. 3.74±3.19, P=0.002) were less severe in the BCS group than in the mastectomy group. Furthermore, the relationships among QOL status and mental health status were more complex in the BCS group than in the mastectomy group (Chi-square minimization p-value: 0.231 vs. 0.469, respectively). Also, depression directly affected QOL in the mastectomy group (R=-0.47), but not in the BCS group.Conclusions: There were differences in QOL and mental health between the BCS and mastectomy groups. SEM is useful for identifying such differences, which can be used to develop strategies for improving QOL.