Lost axillary markers after neoadjuvant chemotherapy in breast cancer patients - data from the prospective international AXSANA (EUBREAST 3) cohort study (NCT04373655).

INTRODUCTION

Marking metastatic lymph nodes before neoadjuvant chemotherapy (NACT) has become increasingly popular in the surgical treatment of breast cancer. A variety of devices are currently in use. However, the significance of lost markers is poorly understood, and their impact on clinical decisions is unclear.

MATERIALS AND

METHODS

Among participants enrolled in the prospective AXSANA cohort study, those planned for target lymph node biopsy (TLNB) or targeted axillary dissection (TAD) with completed post-NACT locoregional therapy (surgery and radiotherapy) by January 21, 2025, were included.

RESULTS

In 88 of 1528 patients (5.8 %), axillary markers could not successfully be removed during surgery after NACT. The lost marker rate differed depending on the marker type (metallic clip/coil 7.0 %, carbon 3.1 %, radar reflector 1.4 %, magnetic seed 0.6 %, radioactive seed 0.0 %, p < 0.001). Additional postoperative imaging was performed in 25 (28.4 %) and further surgery to remove axillary markers was performed in 6 (6.8 %) patients with lost markers. The proportion of patients undergoing axillary lymph node dissection (46.6 % versus 36.5 %, p 0.069) and axillary radiotherapy (51.1 % versus 50.2 %, p 0.748) did not differ between patients with and without lost markers. After an average follow-up of 21.8 months, axillary recurrences occurred in 3 patients (3.3 %) with and 16 patients (1.0 %) without lost markers (rate ratio 2.89, p 0.088).

CONCLUSION

The loss of markers in TLNB/TAD is uncommon and significantly depends on the marking technique. Lost markers may lead to diagnostic uncertainties and additional imaging or surgical procedures.