Targeted Axillary Dissection (TAD) with radiological guidance in post-chemotherapy breast cancer patients: A pilot study

In breast cancer patients, the optimal surgical management of the axilla has been controversial especially in node positive patients. Until recently, axillary lymph node dissection (ALND) was considered standard in such patients. ALND not only provided accurate staging by assessing pathological lymph node status but also ensured locoregional control as well as helped guiding systemic therapy. Nevertheless, it is associated with higher morbidity in terms of lymphedema, shoulder syndrome, recurrent seromas, sensory loss in arm etc. This gradually led to identification of sentinel lymph node biopsy (SLNB) as a feasible alternative with much lesser morbidity. Though SLNB is now considered standard of care in node negative early breast cancer, its role in initially node positive patients who achieve complete clinical axillary response with neoadjuvant chemotherapy (NACT) is still evolving. Initial trials on SLNB in node positive breast cancer patients receiving NACT had high FNR of 13-15%. Attempts to decrease the FNR further, led to evolution of Targeted Axillary Dissection (TAD) which involves marking of suspected lymph node prechemotherapy and then localizing and removing that node along with other sentinel lymph nodes. Various methods of marking and localising the suspected nodes have been reported in literature, but there is lack of consensus on the most appropriate or feasible technique.  While few techniques like radioactive seed localisation has good identification rate, difficulty in procurement, strict regulatory guidelines of use and high cost on radioactive isotopes has prevented its widespread adoption. Also, there is lack of data on targeted axillary dissection from Indian subcontinent.

Through this study, we aim to assess feasibility and performance of targeted axillary dissection utilizing pre-operative and intra-operative ultrasound guidance in node positive breast cancer patients who achieve complete axillary response after NACT. Once the feasibility and accuracy of this technique is established, it will provide a cost-effective option of performing TAD in growing economies as well as resource constraint settings. Also, this study will further guide as to design prospective trial to study long term oncological outcomes of TAD and SLNB in this subset of patients. 

Research Hypothesis

Clipping the positive lymph node pre-NACT and ensuring removal of that node along with other sentinel lymph nodes during SLNB using preoperative/ intraoperative ultrasound should decrease the FNR of SLNB in post-NACT carcinoma breast patients.