ABSTRACT
INTRODUCTION: Many landmark trials have challenged the need for extensive axillary surgery and radiation in breast cancer patients. De-escalation of axillary treatment could potentially result in less breast cancer-related lymphedema (BCRL). Our study aims to define the incidence and trends of BRCL over the last 15 years. METHOD(S): Since 2005, our institution has prospectively screened breast cancer patients for lymphedema during and after treatment with a Perometer. 2,334 women diagnosed with breast cancer with baseline arm volume measurements and at least 2 follow-up measurements were divided into 3 cohorts based on date of surgery (Cohort 1: 2005-2010, Cohort 2:2011-2016, Cohort 3: 2016-2022). The cohorts were selected to coincide with publications of the landmark trials NSABP B-32, ASCOG Z0011, ASCOG Z1071, and EORTC 10981-22023 AMAROS which demonstrated safety in reducing the number of axillary lymph node dissections (ALND). Lymphedema was defined as a relative volume change of 10% or greater from preoperative baseline at least 3 months post-operatively. In cases of bilateral surgery, the weight-adjusted arm volume change equation was utilized. Cohort, age, BMI, axillary surgery type, chemotherapy timing, radiation type, and surgery type were all included in the multivariate analysis. RESULT(S): The overall incidence of BCRL was 12.8%, with a 29.6% incidence for those undergoing ALND and a 6.4% incidence for those undergoing sentinel lymph node biopsy. While the number of ALND performed decreased between cohorts (Figure 1), there was no significant difference in BCRL between assigned cohorts (HR 1.02 (95% CI [0.69, 1.51], p=0.930 for cohort 3 vs cohort 1). On multivariate analysis, significant associations with development of BCRL were identified with older age (HR 1.02;95% CI [1.01, 1.03], p=0.002), higher BMI (HR 1.05;95% CI [1.04, 1.07], p< 0.0001) and ALND (HR increased the risk of (HR 3.67;95% CI [2.62, 5.13], p< .0001). Regional lymph node radiation was not significantly associated with BCRL. CONCLUSION(S): Despite a reduction in the number of ALND performed over time, we did not see a dramatic reduction in the incidence of BCRL. Interestingly, between cohort 2 and cohort 3 there was a stable incidence of ALND which could be related to the COVID pandemic with an increase in more advanced cancers and a decrease in the ability to screen patients for BCRL during that time period.