Abstract OT1-08-01: AXSANA – EUBREAST3: An international prospective multicenter cohort study to evaluate different surgical methods of axillary staging in clinically node-positive breast cancer patients treated with neoadjuvant chemotherapy

Abstract

Abstract Background The optimal surgical staging procedure of the axilla in patients who convert from a clinically positive (cN+) to a clinically negative node status (ycN0) through neoadjuvant chemotherapy is still controversial. Widely diverse techniques such as full Axillary Lymph Node Dissection (ALND), Targeted Axillary Dissection (TAD), Targeted Lymph Node Biopsy (TLNB) and Sentinel Lymph Node Biopsy (SLNB) alone are given preference in different international guidelines. So far, no comparative data on the oncological outcome or the morbidity of the different procedures are available. Further research is needed to safely de-escalate the extent of axillary surgery in this patient group. Trial design The AXSANA study is an international prospective cohort study including cN+ patients converting to ycN0 status and treated with different axillary staging techniques according to the standard at their treating institution. The study was initiated by the EUBREAST network. The trial includes patients with cT1-4c tumors, who present initially with clinically axillary lymph node involvement metastasis scheduled for neoadjuvant chemotherapy. According to an amendment in 2020 the inclusion of patients with highly suspicious nodes without confirmation using a minimally invasive biopsy is allowed. All patients converting to ycN0 status undergo follow-up for 5 years irrespectively of the ypN status. Primary endpoints: Invasive disease-free survival, axillary recurrence rate and health-related quality of life (HRQoL). HRQoL are evaluated using four standardized questionnaires (EORTC QLQ-C 30, EORTC QLQ-BR23, Lymph-ICF and SOC 13) at baseline and after 1, 3 and 5 years after surgery. Secondary endpoints are the feasibility and performance of different axillary staging techniques (detection rate, number of removed lymph nodes and association with complications, arm morbidity and quality of life, operating time and use of clinical and economic resources); impact of learning curve, and the detailed mapping of surgical and oncological treatment standards in different countries. The impact on different regional treatment strategies (radiotherapy, ALND) in patients with ypN0(i+), ypN1(mi) and ypN1 is assessed. Current status of the study: 2347 patients from 247 study sites and 23 countries were enrolled in the study between June 2020 and June 2022. Among 1804 patients with a defined surgical concept 758 women were scheduled for ALND, 722 for TAD, 232 for SLNB, 16 for TLNB and 19 for other procedures. A target lymph node was marked in 1215 patients, most frequently using clips/coils (982, 82.0%), followed by magnetic seeds (100, 8.4%), carbon ink (99, 8.3%), radar marker (21, 1.8%), radioactive seeds (5, 0.4%), and other techniques (8, 0.7%). Citation Format: Thorsten Kühn. AXSANA – EUBREAST3: An international prospective multicenter cohort study to evaluate different surgical methods of axillary staging in clinically node-positive breast cancer patients treated with neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr OT1-08-01.