Abstract P1-12-05: The Impact of Adjuvant Chemotherapy, Including Taxanes, on Breast Cancer-Related Lymphedema Risk

Abstract BACKGROUND: Adjuvant chemotherapy, particularly taxane-based chemotherapies, which are used to treat high-risk breast cancers, has been shown to be efficacious in prolonging overall survival. However, the impact of such therapies on risk of breast cancer-related lymphedema (BCRL) is yet to be fully understood. Available studies have contradictory findings as to whether or not taxanes increase BCRL risk. Unfortunately, methodological flaws, such as not incorporating a preoperative baseline arm volume measurement or utilizing flawed measurement techniques and diagnostic criteria, result in misdiagnosis of the primary outcome of BCRL and it is therefore difficult to draw conclusions from these studies. As such, a more comprehensive understanding of the potential risks associated with these treatment modalities can improve quality of care as patients are better prepared to face a potentially devastating sequela of breast cancer treatment. PURPOSE: The purpose of this study is to determine if chemotherapy administered in the adjuvant setting is an independent risk factor of BCRL, as well as to assess any specific risks of taxane-based chemotherapy on BCRL. METHODS: From 2005 to 2021, 2049 patients treated for breast cancer were enrolled in a prospective BCRL screening trial and screened from preoperative baseline through last follow-up. Screening included objective arm volume measurements via perometry. Chemotherapy data and clinicopathological and demographic characteristics were collected directly from the electronic medical record. Patients who had not received neoadjuvant chemotherapy were eligible for the current study; they were classified based on whether they had received taxane-based chemotherapy, non-taxane chemotherapy only, or no chemotherapy. Relative volume change (RVC) increase ≥10% from preoperative baseline >3 months postoperatively was used to define BCRL. Patients were censored at cancer recurrence or most recent clinic visit. We fit a Cox regression model to estimate adjusted hazard ratios (aHR) for BCRL. The model was adjusted for baseline BMI, axillary lymph node dissection (ALND), regional lymph node radiation (RLNR), age at diagnosis, and smoking history. RESULTS: The eligible cohort included 1759 patients, including 564 (32%) who received taxane-based chemotherapy and 104 (6%) who received non-taxane chemotherapy only. The median follow-up time for the entire cohort was 58 months. 141/1759 (8%) of patients developed BCRL. The median time to develop BCRL was 21 months post-operatively. Compared to no chemotherapy, the aHR associated with taxane-based chemotherapy was 1.04 (95% CI 0.37, 1.8; p = 0.62). Compared to no chemotherapy, the aHR for non-taxane chemotherapy was 0.82 (95% CI 0.67, 1.6; p = 0.86). There was no significant difference between taxane and non-taxane therapies in terms of BCRL risk (p = 0.55). ALND, RLNR, and high BMI remained independent risk factors for BCRL, consistent with the published literature. CONCLUSION: The receipt of adjuvant chemotherapy and specifically adjuvant taxane-based chemotherapy were not associated with increased risk of BCRL in this cohort of 1759 patients at risk of and prospectively screened for BCRL. Citation Format: Amanda W. Jung, Brooke Juhel, Louisa H. Smith, Cheryl L. Brunelle, Elizabeth K. Hausman, Loryn K. Bucci, George E. Naoum, Alphonse G. Taghian. The Impact of Adjuvant Chemotherapy, Including Taxanes, on Breast Cancer-Related Lymphedema Risk [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-12-05.