Low axillary sampling to stage post neoadjuvant axilla in breast cancer patients - A practical approach in developing world

Background

Post-neoadjuvant sentinel lymph node biopsy or targeted axillary dissection in carcinoma breast patients need costly infrastructure, making it out of reach for resource constrained developing countries. This study assesses the diagnostic accuracy of low axillary node sampling to predict the nodal status of the post-chemotherapy node-negative axilla.

Materials and methods

This is a prospective study which included cytology proven node positive carcinoma breast patients who had node negative axilla after chemotherapy and underwent low axillary sampling with complete axillary lymph node dissection. Nodes below second intercostobrachial nerve were sent as low axillary sample.

Results

211 patients with carcinoma breast underwent FNAC of the axillary node prior to neoadjuvant systemic therapy (NAST). Low axillary sampling was performed on 77 patients who had clinically and radiologically node negative axilla after NAST. Out of 77, 24 (31%) had early breast cancer and 32 (41.5%) had T4 disease prior to NAST. In this cohort, 36 patients (47%) had a good biology tumour, 57 (74%) had Grade 3 tumour and 20 (26%) had lymphovascular invasion (LVI). Pathological complete response of breast and axilla was seen in 24 patients (31%). Low axillary sampling had a range of 1–12 nodes with median lymph nodal yield of 6. The false negative rate (FNR) of low axillary sampling was 8.3%. Good tumour biology, post NAST residual breast tumour and lymphovascular invasion were the independent predictors of positive low axillary nodes.

Conclusions

Low axillary sampling is an economical and feasible option to de-escalate axillary surgery with acceptable false negative rate in carcinoma breast patients who had node negative axilla post neoadjuvant systemic therapy.