Survival and axillary recurrence following sentinel node-positive breast cancer without completion axillary lymph node dissection: the randomized controlled SENOMAC trial

Abstract

BackgroundThe role of axillary lymph node dissection (ALND) has increasingly been called into question among patients with positive sentinel lymph nodes. Two recent trials have failed to show a survival difference in sentinel node-positive breast cancer patients who were randomized either to undergo completion ALND or not. Neither of the trials, however, included breast cancer patients undergoing mastectomy or those with tumors larger than 5 cm, and power was debatable to show a small survival difference.MethodsThe prospective randomized SENOMAC trial includes clinically node-negative breast cancer patients with up to two macrometastases in their sentinel lymph node biopsy. Patients with T1-T3 tumors are eligible as well as patients prior to systemic neoadjuvant therapy. Both breast-conserving surgery and mastectomy, with or without breast reconstruction, are eligible interventions. Patients are randomized 1:1 to either undergo completion ALND or not by a web-based randomization tool. This trial is designed as a non-inferiority study with breast cancer-specific survival at 5 years as the primary endpoint. Target accrual is 3500 patients to achieve 80% power in being able to detect a potential 2.5% deterioration of the breast cancer-specific 5-year survival rate. Follow-up is by annual clinical examination and mammography during 5 years, and additional controls after 10 and 15 years. Secondary endpoints such as arm morbidity and health-related quality of life are measured by questionnaires at 1, 3 and 5 years.DiscussionSeveral large subgroups of breast cancer patients, such as patients undergoing mastectomy or those with larger tumors, have not been included in key trials; however, the use of ALND is being questioned even in these groups without the support of high-quality evidence. Therefore, the SENOMAC Trial will investigate the need of completion ALND in case of limited spread to the sentinel lymph nodes not only in patients undergoing any breast surgery, but also in neoadjuvantly treated patients and patients with larger tumors.Trial registration NCT 02240472, retrospective registration date September 14, 2015 after trial initiation on January 31, 2015.

How Pre-operative Sentinel Lymph Node Contrast-Enhanced Ultrasound Helps Intra-operative Sentinel Lymph Node Biopsy in Breast Cancer: Initial Experience

“…The sentinel lymph node (SLN) is defined as the first node to which tumor cells spread from the primary breast cancer site through the defined regional lymphatic channels (LCs) that lead to the axillary regions and other regional lymphatic chains (Cserni 2000;de Boniface et al 2017;Toussaint et al 2011). The status of axillary lymph nodes (ALNs) remains an important prognostic factor that provides valuable information about overall survival to help guide adjuvant treatment decisions (Krag et al 2010;Langer et al 2009;Sol a et al 2013), as well as predict the axillary stage and help in treatment decisions.…”

Is sentinel node biopsy necessary in the radiologically negative axilla in breast cancer?

“…The SOUND [12] and INSEMA [13] trials randomize patients with a negative AUS to no further axillary intervention or SNB, providing much needed RCT evidence on this issue. The SENOMAC [14] trial expands upon the Z11 population, including patients undergoing mastectomy. In clinically node-positive patients, the TAXIS [15] trial will look at survival after selective node clearance as a less extensive surgical option to complete ANC.…”

Management of the axilla in patients with breast cancer and positive sentinel lymph node biopsy: An evidence-based update in a European breast center

“…BOOG 2013-07 and SENOMAC trials propose to answer additional questions not addressed by the Z0011 study by selecting patients with higher tumor burden (up to 3 þ SLNs in the former and up to cT3 lesions in the latter) [32,34,35]. TAXIS trial represents the only European study for patients with a clinically biopsy-proven positive axilla aiming to prove that tailored axillary surgery (removal of detectable positive nodes) with axillary radiotherapy is non-inferior than complete ALND [36].…”