Abstract OT1-04-03: Sentinel lymph node biopsy versus no axillary surgery in early breast cancer clinically and ultrasonographically node negative: A multicentre prospective randomized controlled trial (VENUS trial)
Authors: Duarte Giuliano Mendes , Araújo Danielle Cristina Myiamoto , Jales Rodrigo Menezes , Shinzato Júlia Yoriko , Filho Cassio Cardoso , Torresan Renato Zocchio , Brenelli Fabrício Palermo , Kraft Maria Beatriz de PaulaLeite , Esteves Sergio Carlos Barros , Sarian Luis Otávio Zanatta , Rahal Rosemar MecedoSousa , de Freitas Ruffo , Pessoa Eduardo Carvalho , Lucena Clecio Ênio Murta , Damin Andrea PiresSouto , Biazus Jorge Villanova , Budel Vinicius Milani , de Oliveira Idan , Vieira Rene Aloisio da Costa , Gomes Júlio César Narciso 
Published: March 2022

Background: In early breast cancer, sentinel lymph node biopsy (SLNB) has become the gold standard of axillary evaluation. Although it has less morbidity than axillary lymph node dissection, it may still cause sequelae. Currently, patients selection for SNB has been through physical examination, but presents low sensitivity and high false negative rate. Thus, ultrasonography with biopsy of suspected lymph nodes increases the accuracy. In an attempt to further reduce the morbidity of axillary surgery, it was hypothesized that it would be possible to avoid SLNB in women with early breast cancer. The aim of this study is to compare the SLNB with no axillary surgery as an approach to the axilla in early breast cancer and negative axilla clinical and ultrasonographical. Our trial includes some subsets excluded in others similar ongoing trials: patients that will undergo mastectomy and will receive primary systemic therapy. Trial design: A multicenter, phase III, prospective, open-label, non-inferiority randomized clinical trial, including 10 study sites in Brazil that will randomize 800 early breast cancer patients.Eligibility criteria: Inclusion: woman, age ≥ 18 years, histologic diagnostic of breast carcinoma, tumor ≤ 5 cm (T1 and T2) in all exams, clinically node-negative, ultrasound node-negative or negative core biopsy/fine needle aspiration if suspect lymph node (in this situation is mandatory lymph node tissue in pathologic exam). Exclusion: metastatic disease in biopsy or image before treatment, pregnancy, breastfeed, previous diagnostic of invasive neoplasia (excluding skin cancer no melanoma). It will be allowed mastectomy and neoadjuvant treatment if patient has negative axilla and T1-2 pre-systemic therapy.Intervention and stratification: Participants in experimental group will not be undergo axillary surgery and in control group will be submitted at SLNB. The randomization will be 1:1 ratio and stratified by: tumor size (T1 and T2) and age (≥50 and &lt; 50 years)Specific aims: the primary objective is to access whether omission of axillar surgery is not inferior than SLNB in term of disease-free survival (DFS) at 5 years (primary endpoint). Secondary endpoints are overall survival, locoregional free survival, axillary recurrence rate, to describe surgical early and later complications and to evaluate costs of procedure SLNB or no. Statistical methods: with type I error 5%, power 80% and risk ratio 0.8, considering DFS at 5 years 90% in control group non-inferior DFS at 5 years 85% in experimental group, it was calculated sample size of 400 patients randomized and with follow up in each group (lost estimated 10%). Chi-squares and Fisher's tests will be used for the univariate analyzes, and logistic regression models for adjusted analyzes. Disease-free survival analysis, disease-free survival at a distance, and overall survival will be performed, which will be compared between groups using Kaplan-Meyer curves, log-rank tests and Cox Proportional Hazards-adjusted analyzes. The analyzes will be made intention-to-treat and per protocol.Present and target accrual: the trial was activated at November 2019 and 92 patients were accrued on July 7th 2021. The estimative of finish recruitment is in 2025 and the first data analyses will be made in 2029. The trial is registered in ReBEC (Brazilian register): RBR-8g6jbf. Contact information: Prof. Dr. Giuliano Duarte, - Univertidade Estadual de Campinas - CAISM - UNICAMP, giulianomduarte@gmail.com

Citation Format: Giuliano Mendes Duarte, Danielle Cristina Myiamoto Araújo, Rodrigo Menezes Jales, Júlia Yoriko Shinzato, Cassio Cardoso Filho, Renato Zocchio Torresan, Fabrício Palermo Brenelli, Maria Beatriz de PaulaLeite Kraft, Sergio Carlos Barros Esteves, Luis Otávio Zanatta Sarian, Rosemar MecedoSousa Rahal, Ruffo de Freitas, Jr, Eduardo Carvalho Pessoa, Clecio Ênio Murta Lucena, Andrea PiresSouto Damin, Jorge Villanova Biazus, Vinicius Milani Budel, Idan de Oliveira, Jr, Rene Aloisio da Costa Vieira, Júlio César Narciso Gomes. Sentinel lymph node biopsy versus no axillary surgery in early breast cancer clinically and ultrasonographically node negative: A multicentre prospective randomized controlled trial (VENUS trial) [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr OT1-04-03.