141 Poster - Hospital variation in the use of Sentinel Lymph Node Biopsy for patients with a biopsy diagnosis of ductal carcinoma in situ

Abstract

Background: For patients with the biopsy diagnosis Ductal Carcinoma In Situ (DCIS) a Sentinel Lymph Node Biopsy (SLNB) can be considered, since 20% of these patients have occult invasive cancer. The indications for SLNB vary between guidelines; some guidelines advise against SLNB if it is possible to keep the lymph vessels draining the tumour bed intact and other guidelines consider the risk factors for underestimation of invasive breast cancer and aim at maximizing the use of SLNB in patients who turn out to have invasive breast cancer. In the Dutch guideline several risk factors are identified, however without any indication on how to balance these factors. We therefore aimed to determine the variation in the SLNB rate among Dutch hospitals and to assess the accuracy of the decision whether or not to perform SLNB.