Axillary reverse mapping: Is it feasible in locally advanced breast cancer patients?

Axillary dissection is associated with a high incidence of lymphedema, which has been brought down with the introduction of sentinel lymph node biopsy (SLNB) in patients with early breast cancer. However, sentinel lymph node biopsy is not widely accepted in patients of locally advanced breast cancer (LABC) [T3N1, Any T4, Any N2-3 with no distant metastasis] after neo-adjuvant chemotherapy (NACT) and these patients routinely undergo axillary lymph node clearance. Axillary reverse mapping (ARM) with blue dye has the potential to differentiate the arm lymphatics from the breast lymphatics and it can be used to decrease lymphedema in patients undergoing ALND by preserving these lymphatics. However, ARM in LABC patients is yet to be accepted as the standard of care.

51 patients of locally advanced breast carcinoma were included in the study from May 2011 to May 2012. All patients received neo-adjuvant chemotherapy followed by modified radical mastectomy. Axillary reverse mapping (ARM) was carried out using blue dye. 2 ml of methylene blue dye was injected intradermal, upper medial aspect of the ipsilateral arm. The number, size and site and distribution of lymph nodes identified were recorded and the nodes were labelled as ARM nodes and complete axillary dissection was carried out.

Blue nodes were identified in 45 (88.2%) out of the 51 patients. The average number of ARM nodes identified was 4.03 ± 0.28 [range 1-8]. In majority (77.8%) of the cases, nodes were located in the triangle formed by axillary vein above, below by the first intercostobrachial nerve and medially by the chest wall/serratus anterior. In patients with complete or partial response to NACT, ARM and breast axillary LN were negative in 63.3% patients whereas 36.6% had positive breast but negative ARM nodes. In this study we did not intend to preserve any ARM nodes but in 90% of these cases, at least one ARM node had to be removed or was injured during axillary clearance. ARM nodes could be identified in 15 (83.3%) out of the 18 patients with stable or progressive disease following ARM. 12 (80%) out of these 15 cases demonstrated positive ARM and breast LN whereas 3 (20%) patients had positive breast but negative ARM nodes. Skin tattooing (82.3%) was the most common complication observed in our study.

Identification rates of ARM nodes can be improved by injecting the blue dye in the upper medial aspect of the arm at the time of induction. Majority of the arm nodes lie between the axillary vein and the first intercostobrachial nerve. It is difficult to preserve the ARM nodes in patients of LABC, who have had good response to NACT and in patients of LABC with poor response to NACT, the incidence of metastasis in ARM nodes is quite high. Therefore, ARM is not a feasible option in patients with locally advanced breast cancer.