Does increased tumor burden of sentinel nodes in breast cancer affect detection procedure?

Abstract Numerous studies have shown that sentinel lymph node biopsy (SLN) has a high level of detection sensitivity. Successful detection procedure depends on the amount of radioactivity and accumulation of blue dye in the SN. Our aim was to relate the differences observed in intraoperative SN presentation to tumor burden, characteristics of the primary tumor and patient attributes. Our retrospective analysis included 369 patients undergoing SLN in the Department of Gynecology of the University Hospital of Zurich within five years. Data was collected from the patients (age, BMI), the primary tumor (size, grading, hormone receptors, HER2 status) and the SNs removed (counts per second [cps], blue dye, size of nodular metastasis, extracapsular involvement, number of SNs excised). Because patients typically had more than one SN, a linear mixed-effects model was used to account for the clustering within one patient. SNs presented with significantly lower radioactivity in elderly (−1.8%/year, p