Yuri Hazawa - Department of Nursing and Surgical Science, Sapporo Medical University Postgraduate School of HealthScience, Sapporo, Japan
Goro Kutomi - Department of Surgery, Surgical Science and Oncology, Sapporo Medical University Postgraduate School ofMedicine, Sapporo, Japan
Hiroaki Shima - Department of Surgery, Surgical Science and Oncology, Sapporo Medical University Postgraduate School ofMedicine, Sapporo, Japan
Toshio Honma - Department of Breast Surgery, Sapporo Breast Surgical Clinic, Sapporo, Japan
Tosei Ohmura - Department of Surgery, Higashi-Sapporo Hospital, Sapporo, Japan
Asaka Wada - Department of Surgery, Surgical Science and Oncology, Sapporo Medical University Postgraduate School ofMedicine, Sapporo, Japan

Background: Improving health-related quality of life (HRQOL) has become afundamental goal of breast cancer management. This study aimed to examine thedifferences between the QOL outcomes of breast-conserving surgery (BCS) andmastectomy. We also established structural equation models for BCS andmastectomy to elucidate their unique effects on QOL. Methods: Between July ۲۰۱۹ and November ۲۰۱۹, ۲۵۴ patients, who werescheduled to visit one of four clinics, were recruited for this study. We evaluatedHRQOL using various questionnaires, such as the BREAST-Q, EQ-۵D-۵L, andHospital Anxiety and Depression Scale (HADS). The relationships among theexamined clinical indicators were evaluated using structural equation modeling (SEM). Results: The QOL scores of the BCS group were better than those of themastectomy group (۰.۸۵±۰.۱۲۹ vs. ۰.۸۱±۰.۱۲, P=۰.۰۲۰). Also, anxiety (۲.۹۴±۲.۹۵vs. ۳.۸۱±۳.۰۸, P=۰.۰۲۵) and depression (۲.۵۵±۲.۷۷ vs. ۳.۷۴±۳.۱۹, P=۰.۰۰۲) wereless severe in the BCS group than in the mastectomy group. Furthermore, therelationships among QOL status and mental health status were more complex inthe BCS group than in the mastectomy group (Chi-square minimization p-value:۰.۲۳۱ vs. ۰.۴۶۹, respectively). Also, depression directly affected QOL in themastectomy group (R=-۰.۴۷), but not in the BCS group. Conclusions: There were differences in QOL and mental health between theBCS and mastectomy groups. SEM is useful for identifying such differences,which can be used to develop strategies for improving QOL.

Quality of life, breast-conserving surgery, mastectomy, structural equation modeling