Abstract P2-14-10: Axillary Reverse Mapping Aids in Reducing the Rates of BCRL in Underserved Ethnically Diverse Population
Authors: Bhimani Fardeen , McEvoy Maureen , Johnson Kelly , Feldman Sheldon 
Published: March 2023

Abstract
Background: Breast Cancer Related Lymphedema (BCRL), is a long-term side effect affecting the patient’s quality of life after lymph node surgery. Historically BCRL is seen in 5-7% and 15-40% of patients undergoing sentinel lymph node biopsy (SLNB) and axillary lymph node dissection (ALND) respectively; with the risk increasing two-fold in low-income and ethnic minority groups. Axillary Reverse Mapping (ARM) is a novel technique to distinguish drainage pathways of the arm and breast, and prior studies have reported significantly lower rates of BCRL with ARM. Lymphatic re-approximation can prevent and/or reduce lymphedema rates in cases where crossover nodes are encountered. Furthermore, blue nodes can be preserved during ALND; however, if resected during ALND, lymphatic venous (LYMPHA) procedure can help to restore lymphatic flow. However, there is a paucity of literature looking at the utility of ARM in ethnically minority groups. Therefore, we aimed to evaluate the prevalence of lymphedema in our patient population with breast cancer undergoing SLNB and ALND using ARM and in turn compare these findings to historical controls.
Materials & Methods: A retrospective study was carried out on patients who underwent axillary surgery with ARM from January 2019 to July 2021. Patient demographics such as age, BMI, gender, and ethnicity were recorded. Patients undergoing mastectomy vs breast conservation with SLNB ± ALND associated with ARM were monitored for lymphedema for a year at 3-month intervals using SOZO® scores, and then for another 2 years clinically. At each follow-up, SOZO® scores were computed using bioimpedance spectroscopy and compared to preoperative baseline scores.
Results: A total of 142 patients’ data was evaluated, of which 83.8% belonged to the minority group (African American = 46, Hispanic = 63, Asian = 10). Mean BMI accounted for 29.1+5.31. Breast conservation surgery and mastectomy were performed in 71.8% (n=102) and 28.1% (n=40) of patients respectively. SLNB was performed on 88.7% (n=126) of the patients and ALND was carried out on 11.3% (n=16). Furthermore, 73.9% (n=105) of the patients underwent radiation therapy. Positive lymph nodes were identified in 24.6% (n=35) of patients. Blue nodes and blue lymphatics were encountered in 17.6% (n=25) and 32.4% (n=46) of patients respectively. Out of the blue nodes identified (n=25), 44% (n=11) were excised and 32% (n=8) were diagnosed as crossover nodes. All the crossover nodes were resected but none of them contributed to the development of lymphedema. Moreover, 90.9% of the patients with blue lymphatics underwent lymphatic re-approximation after excision of the blue nodes. Of the 142 patients, 59 had a three-month follow-up of which 2 patients (3.4%) developed clinical lymphedema diagnosed via SOZO® who had undergone SLNB which resolved by 6-month follow-up. Additionally, compared to the historical incidence of BCRL which accounts for up to 40.4% in ethnic minorities, we found a significantly lower incidence of lymphedema (p&lt; 0.001) in our patient population. Moreover, in our study, ALND and radiation therapy did not contribute to lymphedema rates.
Conclusion: ARM procedure can significantly lower BCRL even in ethnically minority groups. 3.4% of patients undergoing SLNB developed BCRL, which was significantly lower than historically reported data. Furthermore, in our study, no patients who underwent ALND developed lymphedema. Also, crossover nodes or radiation therapy did not contribute to the development of lymphedema after surgery demonstrating the effectiveness of ARM technique. Further studies with larger sample size and longer follow-up duration are necessary to better understand the utility of ARM technique in this population.
Table 1 Baseline characteristics and follow-up data of the patients undergoing Axillary Reverse Mapping with SLNB ± ALND
Citation Format: Fardeen Bhimani, Maureen McEvoy, Kelly Johnson, Sheldon Feldman. Axillary Reverse Mapping Aids in Reducing the Rates of BCRL in Underserved Ethnically Diverse Population [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 P2-14-10.