Axillary sentinel lymph node biopsy in patients with pure ductal carcinoma in situ of the breast

Hypothesis: A sentinel lymph node (SLN) biopsy should not be considered a standard procedure in the treatment of all patients with ductal carcinoma in situ (DCIS) of the breast if the lesion is completely excised by radical surgery and there are free margins of resection. Design: Prospective case series. Setting: Department of breast surgery of a comprehensive cancer center. Patients: From January 1, 1998, to December 1, 2001, 223 unselected consecutive patients affected by pure DCIS of the breast underwent an SLN biopsy. Results: Metastases in the SLN were detected in 7 (3.1%) of the 223 patients, and complete axillary dissection was subsequently performed in all these patients but 1. Of these 7 patients, 5 had only micrometastases in the SLNs; and in the 6 patients treated with complete axillary dissection, the SLN was the only positive node. Conclusions: Because of the low prevalence of metastases, an SLN biopsy should not be considered a standard procedure in all patients with DCIS. In patients with pure DCIS in whom the lesion is completely excised by radical surgery, an SLN biopsy could be avoided. It could be considered in patients with DCIS undergoing mastectomy, in whom there exists a higher risk of harboring an invasive component using definitive histologic features, like large solid tumors or diffuse or multicentric microcalcifications; in these patients, an SLN biopsy cannot be performed at a later operation. Complete axillary dissection may not be mandatory if the SLN is micrometastatic.