Abstract
Background. A proportion of those diagnosed preoperatively with ductal carcinoma-in-situ (DCIS) will be histologically upgraded to invasive carcinoma. Repeat surgery for sentinel lymph node (SLN) biopsy will be required if it had not been included with the initial surgery. We reviewed the outcome of SLN biopsy performed with the initial surgery based on a preoperative diagnosis of DCIS and aimed to identify patients at risk of histological upgrade. Methods. Retrospective review of 294 consecutive female patients diagnosed with DCIS was performed at our institute from January 1, 2001, to December 31, 2008. Results. Of the 294 patients, 132 (44.9%) underwent SLN biopsy together with the initial surgery. The SLN was positive for metastases in 5 patients, all of whom had tumours that were histologically upgraded. Histological upgrade also occurred in 43 of the 127 patients (33.9%) in whom the SLN was negative for metastases. On multivariate analysis, histological upgrade was more likely if a mass was detected on mammogram, if the preoperative diagnosis was obtained with core biopsy and if microinvasion was reported in the biopsy. Conclusion. Patients in whom a preoperative diagnosis of DCIS is likely to be upgraded to invasive carcinoma will benefit from SLN biopsy being performed with the initial surgery.