SAVI SCOUT® localization of metastatic axillary lymph node prior to neoadjuvant chemotherapy for targeted axillary...

In clinically node-positive breast cancer, axillary staging after neoadjuvant chemotherapy (NAC) is optimized with targeted axillary dissection (TAD), which includes removal of the biopsy-proven metastatic lymph node (LN) in addition to sentinel lymph nodes (SLN). Localization of the clipped node is currently performed post-NAC; however, technical limitations can make detection and localization of the treated LN challenging. We prospectively evaluated the feasibility of localizing the metastatic LN with a SAVI SCOUT® reflector (SAVI) prior to NAC for targeted removal at surgery.

Twenty-five patients with stage 2/3 breast cancer underwent ultrasound-guided localization of the biopsy-proven LN with SAVI prior to NAC. After NAC, patients with clinical response underwent TAD. Primary outcome measures were rate of successful localization, days between insertion of SAVI and axillary surgery, frequency of retrieval of clipped node, and frequency of SAVI-LN as SLN.

After NAC, 23/25 (92%) had clinical axillary down-staging and underwent TAD. Two patients with persistent palpable axillary disease underwent ALND for initial staging. Axillary surgery was performed at an average of 141 days post-SAVI insertion and the SAVI was successfully retrieved in all cases. Among 23 patients undergoing TAD, the SAVI was retrieved within a LN in all patients, whereas clip migration was observed in two patients. The median SLN removed was 4, and SAVI-LN was SLN in 22/23 patients. Axillary pCR rate was 44%.

Localizing a metastatic LN with SAVI reflector prior to NAC for targeted removal at surgery is feasible and may provide technical and logistical advantages over axillary localization post-NAC.

Clinical trials.gov identifier: NCT03411070.