Sentinel lymph node biopsy (SLNB) has been adopted by some physicians in the evaluation of ductal carcinoma in situ (DCIS). In a review of the current literature, we found no convincing data that SLNB is warranted as standard of care in newly diagnosed DCIS. Although lymph node invasion is present in 2% of women with traditional axillary lymph node dissection (ALND), as a result of the excellent prognosis of DCIS, it is not recommended. However, the detailed evaluation of the lymph node(s) with SLNB raises the issue that perhaps patients at risk for recurrence can be identified early and be treated aggressively without the morbidity associated with ALND. Limited data suggest that, with the use of more sensitive methods for detection of cytokeratin-positive cells, the prevalence of positive lymph nodes in pure DCIS is approximately 2%-13%. In high-risk DCIS or DCIS with microinvasion, the prevalence is 8%-20%. Several limited retrospective studies with long-term follow-up have not demonstrated an adverse relapse-free or overall survival effect for women with immunohistochemically (IHC) positive cells in the lymph nodes compared with those with negative IHC results in the lymph nodes. Sentinel lymph node biopsy in DCIS is associated with known risks, and health care benefits, if any, have not been demonstrated. Sentinel lymph node biopsy is not recommended in patients with DCIS.