Breast cancer recurrence after sentinel lymph node biopsy

Objective: To look into the pattern of breast cancer recurrence following mastectomy, breast conservative surgery and radiotherapy or chemotherapy after SLNB at our institution. Methods: Between January 2005 and December 2014, all patients diagnosed with breast cancer with clinically negative axilla, underwent SLNB. We reviewed their medical records to identify pattern of cancer recurrence. Results: The median follow-up was 35.5 months. Eighty five patients (70.8%) had a negative sentinel lymph node (SLN) and subsequently had no further axillary treatment, one of them (1.2%) developed axillary recurrence 25 months postoperatively. Twenty five patients (20.8%) had a positive SLN (macrometastases) and subsequently had immediate axillary lymph node dissection (ALND). Ten patients (8.3%) had a positive SLN (micrometastases). In the positive SLN patients (macrometastases and micrometastases), there were two ipsilateral breast recurrences (5.7%), seen three and four years postoperatively. Also in this group, there was one (2.9%) distant metastasis to bone three years postoperatively. Conclusion: In this series, the clinical axillary false negative rate for SLNB was 1.2% which is in accordance with the published literature. This supports the use of SLNB as the sole axillary staging procedure in breast cancer patients with negative SLNB. Axillary lymph node dissection can be safely omitted in patients with micrometastases in their sentinel lymph node(s).