Targeted Axillary Node Dissection Using Sirius Pintuition GPSDetectTM Marker Navigation: A Retrospective Multicenter Case Series

Background and purpose: Targeted axillary node dissection (TAD) decreases the false negative rate of sentinel node biopsy through selective resection of the core biopsy proven metastatic node alongside sentinel node dissection using dual tracer technique1. This study aimed to assess the effectiveness and accuracy in TAD with Sirius Pintuition GPSDetectTM. Methods: Patients undergoing TAD with a Pintuition marker were identified from July 2022-May 2023. Patients receiving neoadjuvant chemotherapy (NACT) and non-NACT patients were included. Cases were performed by two surgeons and marker placement was performed by five radiologists. Primary endpoints were successful Pintuition marker axillary nodal placement, localization, and retrieval. Secondary endpoints were days of placement before surgery, and lymph node pathologic status. Results:24 patients underwent US guided placement of the Pintuition marker. In all patients, the marker retrieval rate was 100%. A total of 18 patients underwent TAD after completion of NACT. Average number of days from US localization to TAD was 5 days and average number of sentinel lymph nodes (SLN) removed was 2. Of the 18 patients that underwent NACT, 10 had the Pintuition marker placed after NACT. Average days from marker localization to TAD was 7 days. Eight patients had marker placement prior to NACT with average of marker placement 167 days prior to surgery. The average number of SLN retrieved was 4. 7 patients had no evidence of residual nodal disease, 2 had isolated tumor cells in the TAD node, and 6 had macrometastatic disease. Conclusions: This is the first USA study examining the efficacy of the Sirius Pintuition system in TAD. The system safely and effectively targets the intended axillary node for surgical retrieval in both NACT and non-NACT patients. The surgeons using the system felt it was easy to use and the directional navigation alignment capability was beneficial in retrieving the targeted lymph node.Tabled 1N=24Mean age (years)54 (range 32-75)Breast surgery:Partial mastectomy10 (42%)Skin-sparing mastectomy14 (58%)Histology:Invasive ductal22Invasive lobular1Mixed ductal-lobular1ER+/PR+/Her2-15ER+/PR+/Her2+2ER-/PR-/Her2+2Triple negative4Clinical T stage:T16T214T34Received neoadjuvant chemotherapy18 (75%)Number of suspicious nodes seen on US:1142535Average cortex size seen on US (cm)0.9 (range: 0.3-3)Number of sentinel nodes excised with TAD-mean3(range: 1-6)Clip identified in sentinel node24 (100%)ALND performed6 (25%)Total number of nodes removed on axillary dissection-mean7 (range:4-9) Open table in a new tab References: 1. Selective surgical localization of axillary lymph nodes containing metastases in patients with breast cancer: a prospective feasibility trial. Caudle AS, Yang WT, Mittendorf EA, et al. JAMA Surg. 2015;150:137–143.Base unit providing real time navigationShow full captionAudio and visual feedback50 mm detectionSingle calibrationUse normal metallic instrumentsView Large Image Figure ViewerDownload Hi-res image Download (PPT)Tabled 1N=24Mean age (years)54(range 32-75)Breast surgery:Partial mastectomy10 (42%)Skin-sparing mastectomy14 (58%)Histology:Invasive ductal22Invasive lobular1Mixed ductal-lobular1ER+/PR+/Her2-15ER+/PR+/Her2+2ER-/PR-/Her2+2Triple negative4Clinical T stage:T16T214T34Received neoadjuvant chemotherapy18 (75%)Number of suspicious nodes seen on US:1142535Average cortex size seen on US (cm)0.9(range: 0.3-3)