Targeted Removal of Axillary Lymph Nodes After Carbon Marking in Patients with Breast Cancer Treated with Primary Chemotherapy

Applicability of magnetic seeds for target lymph node biopsy after neoadjuvant chemotherapy in initially node-positive breast cancer patients: data from the AXSANA study

PURPOSE

Currently, various techniques are available to mark and selectively remove initially suspicious axillary lymph nodes (target lymph nodes, TLNs) in breast cancer patients receiving neoadjuvant chemotherapy (NACT). To date, limited data are available on whether the use of magnetic seeds (MS) is suitable for localizing TLNs. This study aimed to investigate the feasibility of MS in patients undergoing target lymph node biopsy (TLNB) or targeted axillary dissection (TAD) after NACT.

METHODS

Prospective data from the ongoing multicentric AXSANA study were extracted from selected patients in whom the TLN had been marked with an MS before NACT and who were enrolled from June 2020 to June 2023. The endpoints of the analysis were the detection rate, the rate of lost markers, and the potential impairment on magnetic resonance imaging (MRI) assessment.

RESULTS

In 187 patients from 27 study sites in seven countries, MS were placed into the TLN before NACT. In 151 of these, post-NACT surgery had been completed at the time of analysis. In 146 patients (96.0%), a TLN could successfully be detected. In three patients, the seed was removed but no lymphoid tissue was detected on histopathology. The rate of lost markers was 1.2% (2 out of 164 MS). In 15 out of 151 patients (9.9%), MRI assessment was reported to be compromised by MS placement.

CONCLUSION

MS show excellent applicability for TLNB/TAD when inserted before NACT with a high DR and a low rate of lost markers. Axillary MS can impair MRI assessment of the breast.

TRIAL REGISTRATION NUMBER

NCT04373655 (date of registration May 4, 2020).

Image-Guided Localization Techniques for Metastatic Axillary Lymph Nodes in Breast Cancer; What Radiologists Should Know

Targeted axillary dissection (TAD) is an axillary staging technique after NACT that involves the removal of biopsy-proven metastatic lymph nodes in addition to sentinel lymph node biopsy (SLNB). This technique avoids the morbidity of traditional axillary lymph node dissection and has shown a lower false-negative rate than SLNB alone. Therefore, marking positive axillary lymph nodes before NACT is critical in order to locate and remove them in the subsequent surgery. Current localization methods include clip placement with intraoperative ultrasound, carbon-suspension liquids, localization wires, radioactive tracer-based localizers, magnetic seeds, radar reflectors, and radiofrequency identification devices. The aim of this paper is to illustrate the management of axillary lymph nodes based on current guidelines and explain the features of axillary lymph node markers, with relative advantages and disadvantages.

Axillary Staging after Neoadjuvant Chemotherapy for Initially Node-Positive Breast Carcinoma in Germany: Initial Data from the AXSANA study

Introduction To date, the optimal axillary staging procedure for initially node-positive breast carcinoma patients after neoadjuvant chemotherapy (NACT) has been unclear. The aim of the AXSANA study is to prospectively compare different surgical staging techniques with respect to the oncological outcome and quality of life for the patients. Little is known about current clinical practice in Germany. Material and Methods In this paper we analyzed data from patients enrolled in the AXSANA study at German study sites from June 2020 to March 2022. Results During the period under investigation, 1135 patients were recruited at 143 study sites. More than three suspicious lymph nodes were initially found in 22% of patients. The target lymph node (TLN) was marked in 64% of cases. This was done with clips/coils in 83% of patients, with magnetic seeds or carbon suspension in 8% each, and with a radar marker in 1% of patients. After NACT, targeted axillary dissection (TAD) or axillary lymphadenectomy (ALND) were each planned in 48% of patients, and sentinel lymph node biopsy alone (SLNB) in 2%. Clinically, the nodal status after NACT was found to be unremarkable in 65% of cases. Histological lymph node status was correctly assessed by palpation in 65% of patients and by sonography in 69% of patients. Conclusion At the German AXSANA study sites, TAD and ALND are currently used as the most common surgical staging procedures after NACT in initially node-positive breast cancer patients. The TLN is marked with various markers prior to NACT. Given the inadequate accuracy of clinical assessment of axillary lymph node status after NACT, it should be questioned whether axillary dissection after NACT should be performed based on clinical assessment of nodal status alone.

False-negative rate in the extended prospective TATTOO trial evaluating targeted axillary dissection by carbon tattooing in clinically node-positive breast cancer patients receiving neoadjuvant systemic therapy

PURPOSE

In clinically node-positive breast cancer patients receiving neoadjuvant systemic therapy (NST), nodal metastases can be initially marked and then removed during surgical axillary staging. Marking methods vary significantly in terms of feasibility and cost. The purpose of the extended TATTOO trial was to report on the false-negative rate (FNR) of the low-cost method carbon tattooing.

METHODS

The international prospective single-arm TATTOO trial included clinically node-positive breast cancer patients planned for NST from November 2017 to January 2021. For the present analysis, patients who received both the targeted procedure with or without an additional sentinel lymph node (SLN) biopsy and a completion axillary lymph node dissection (ALND) were selected. Primary endpoint was the FNR.

RESULTS

Out of 172 included patients, 149 had undergone a completion ALND. The detection rate for the tattooed node was 94.6% (141 out of 149). SLN biopsy was attempted in 132 out of 149 patients with a detection rate of 91.7% (121 out of 132). SLN and tattooed node were identical in 58 out of 121 individuals (47.9%). The combined procedure, i.e. targeted axillary dissection (TAD) was successful in 147 of 149 cases (98.7%). Four out of 65 patients with a clinically node-negative status after NST had a negative TAD but metastases on ALND, corresponding to a FNR of 6.2%. All false-negative TAD procedures were performed in the first 2 years of the trial (2018-2019, p = 0.022).

CONCLUSION

Carbon tattooing is a feasible marking method for TAD with a high detection rate and an acceptably low FNR. The TATTOO trial was preregistered as prospective trial before initiation at the University of Rostock, Germany (DRKS00013169).