Axillary reverse mapping (ARM): Initial results of phase II trial in preventing lymphedema after lymphadenectomy

Introduction. Axillary reverse mapping (ARM) is unproven in preventing lymphedema. The purpose of this study is to evaluate lymphedema rates with ARM added to lymphadenectomy. Methods. In this IRB approved study, 156 cases of SLNB/ALND from May 2007 to March 2010 were prospectively accrued to the study. Patients with an increase in arm volume greater than 20% over the contralateral side were considered to have lymphedema. Data was collected on identification and variations in lymphatic drainage, nodal status, ARM lymphatics preservation rate, adjuvant treatment (XRT, chemo) and lymphedema rate. Results. 114 patients underwent SLNB only and 42 patients underwent ALND after SLNB, with a SLN identification rate of 100%. Median age was 56.9(±12.5) and BMI was 29.4(±6.9). Mean follow up was 14.6±9.4 months. ARM lymphatics were near or in the SLN field in 45/114 (39%) of the SLNB cases and in 34/42 (81%) of the ALND. ARM nodes were preserved in 92.3% of the cases (144/156). A total of 12 ARM nodes were resected because of crossover or suspicious appearance. The 2 ARM nodes involved by malignancy were in heavily positive axilla (>5 positive nodes). Lymphedema was diagnosed in 3.5% (4/114) of the SLNB cases and 7%(3/42) of the combined SLNB+ALND cases. 2.9% (4/140) of the patients who had the ARM lymphatics preserved and 18.7%(3/16) who had it transected developed clinical lymphedema. No regional recurrences were seen. Conclusion. Preserving the ARM nodes is safe and resulted in a low incidence of postoperative lymphedema after SLNB and ALND.