Objective: The purpose of our study is to further clarify the incidence of ductal carcinoma in situ (DCIS) patients that are upstaged upon final pathology and/or have metastatic disease in the axilla.
Methods: All patients were diagnosed with DCIS or DCIS with microinvasion (DCISm) on their diagnostic biopsy and received a sentinel lymph node (SLN) biopsy between 1994 and 2004. Six hundred seventy-five patients were divided into 613 patients with DCIS and 62 patients with DCISm.
Results: Sixty-six of 675 (10%) were upstaged to invasive cancer. Fifty-five of 613 (9%) patients with DCIS were upstaged, whereas 11 of 62 (18%) patients with DCISm were upstaged. Forty-nine of 675 (7%) patients had +SLN. Twenty-two of 49 (45%) patients with +SLN had invasive carcinoma or DCISm on final histology.
Conclusions: After review of histology, grade, type of biopsy, and mammographic findings, the combined findings of high grade, mass by mammography, and microinvasion predict patients at higher risk for invasive carcinoma. Selective utilization of SLN biopsy in DCIS is recommended.