The impact of sentinel lymph node biopsy and magnetic resonance imaging on important outcomes among patients with ductal carcinoma in situ.

The objective of this systematic review was to determine the impact of sentinel lymph node (SLN) biopsy and breast magnetic resonance imaging (MRI) on important outcomes for patients with ductal carcinoma in situ. We identified no study that directly evaluated important outcomes for SLN biopsy. So, we determined the incidence of SLN metastases among patients with ductal carcinoma in situ. Using American Joint Committee on Cancer criteria, the incidence of pN1 and pN1(mic) SLN metastases were 0.9% and 1.5%, respectively. Because the incidence of SLN metastasis is very low, SLN biopsy is not likely to affect important outcomes. We identified one study that directly evaluated important outcomes after breast MRI. In this study, the use of MRI did not affect local recurrence rates after breast-conserving surgery and radiation. Although MRI may identify occult multicentric or contralateral breast cancer in some patients, it may also lead to unnecessary biopsies and overtreatment.