Non-visualized sentinel nodes in breast cancer patients; prevalence, risk factors, and prognosis

Background Evidence and consensus is lacking in international guidelines regarding axillary treatment recommendations for patients in whom a sentinel lymph node (SLN) cannot be visualized (non-vSLN) during the sentinel node procedure. In this study we aimed to determine the prevalence of non-vSLNs in a Dutch population of breast cancer patients and to examine predictors and survival rate for non-vSLN. Methods A nationwide, retrospective, population-based study was performed including 116,920 patients with invasive breast cancer who underwent a SLN procedure in the Netherlands between January 2005 and December 2013. Results Of the 76,472 clinically negative patients who underwent a SLN procedure, 1924 patients (2.5%) had a non-vSLN, of whom 1552 (80.7%) underwent an ALND. Multivariate analysis showed predictive factors for non-vSLN: older age ( p