Axillary Reverse Mapping?Factors Affecting ARM Node Detection and Its Role in Preventing Lymphedema in Node Negative Early Breast Cancer Patients

Abstract

Background: Sentinel lymph node (SLN) imaging is an established tool, while axillary reverse mapping (ARM) for early breast cancer is still evolving. Lymphedema is a vexing complication that can be avoided if ARM node is preserved. Objective: Our primary objective is to study the factors influencing ARM node identification in Positron emission tomography (PET) -reported node negative early breast cancer patients, and our secondary objective is to study the incidence of lymphedema in 18Fluoro Deoxy Glucose node negative (i.e., noncancerous node) breast cancer patients undergoing axillary lymph node dissection (ALND) by preserving the ARM node. Materials and methods: Forty-eight arms of 45 breast cancer pooled patients with FDG negative nodes underwent sentinel lymph node, SLN imaging using the 99mTc Sulfur colloid (99mTc SC, filtered), prior to surgery to rule out microscopic nodal disease. All patients were subjected to ARM on the day of surgery prior to mastectomy ? ALND. Results: Factors (technical and clinicopathological) affecting ARM node identification were analyzed. Colloid preparation was optimized based on heating temperature, duration of heating, radiochemical purity, labeling efficiency, and particle size. Ideal parameters were identified. 18 patients underwent both mastectomy and ALND. 99 SLN were harvested. ARM nodes were successfully identified in all patients. 98 percent of ARM nodes were found at locations different from breast draining nodes, i.e., SLN. No significant differences were observed between the incidence of SLN metastases and clinico pathological features. Conclusions: ARM is yet to be recognized as an imaging tool in routine practice. This study shows that standardization of technique can successfully avoid adverse factors that can affect ARM node identification. Only 2 out of 45 patients (4%) developed lymphedema, which is quite encouraging, indirectly validating the hypothesis that arm draining node is different from nodes draining the breast; hence, preserving ARM node can avoid lymphedema.

Keywords

• SLN
• ALND
• 99mTc sulfur colloid
• lymphedema
• ARM