Breast Edema Following Breast-Conserving Surgery and Radiotherapy: Patient-Reported Prevalence, Determinants, and Effect on Health-Related Quality of Life.

BACKGROUND: The association between lymphedema of the arm and impaired health-related QoL (HR-QoL) has led to changes in clinical practice. However, data on lymphedema of the breast (ie, breast edema) are lacking. We prospectively evaluated patient-reported prevalence and determinants of breast edema and its effect on patient-reported HR-QoL and breast pain. METHODS: We prospectively included 836 patients undergoing breast-conserving surgery followed by radiotherapy between October 2013 and October 2016 (UMBRELLA cohort). Patient-reported breast edema, HR-QoL, and breast pain were assessed by means of European Organisation for Research and Treatment of Cancer-C30/BR23 before starting radiotherapy and at 3, 6, 12, and 18 months thereafter. We assessed which patient, tumor, and treatment characteristics were associated with breast edema. With mixed-effects models, we assessed the impact of breast edema on patient-reported HR-QoL domains and breast pain over time, adjusting for confounders. RESULTS: Within a median follow-up of 28 months (interquartile range [IQR] = 15), 207 (24.8%) patients reported breast edema at some point in time. Prevalence of breast edema was highest at 6 months (12.4%, 95% confidence interval [CI] = 10.0 to 14.7). Larger tumor size, oncoplastic surgery, axillary lymph node dissection, locoregional radiotherapy, radiotherapy boost on the tumor bed, and adjuvant chemotherapy were associated with breast edema. Breast edema was independently associated with more breast pain and with poorer QoL, physical functioning, and body image. CONCLUSIONS: Breast edema occurs frequently within the first year after breast-conserving surgery and radiotherapy and is independently associated with impaired HR-QoL and more breast pain. This information is important for use in clinical practice and should be discussed with patients during shared decision making.