Multicenter prospective trial of feasibility of delaying sentinel node biopsy in DCIS patients undergoing mastectomy

In patients with ductal carcinoma in situ (DCIS) undergoing mastectomy, sentinel lymph node biopsy (SLNB) is routinely performed due to the possibility of upstaging. However, invasive upstaging occurs only in a small subset of patients, and the majority of SLNBs are unnecessary and potentially harmful. A multicenter prospective study in South Korea evaluated the feasibility of omitting SLNB during initial mastectomy in patients with DCIS. The study enrolled DCIS patients scheduled for mastectomy. SLNs were intraoperatively localized by tagging sutures and surgical clips. Secondary SLNB was performed in patients with final diagnosis of invasive disease. The primary endpoint was the detection rate of localized SLNs during secondary surgery. A total of 75 patients with 78 DCIS lesions were enrolled. Five cases underwent SLNB during initial surgery due to palpable lymph nodes. Invasive upstaging was seen in 17 patients, and among them, 11 patients underwent secondary SLNB, with a median interval of 26 days. SLNs were not detected in the first two patients with nodes marked with absorbable sutures. In the subsequent 9 cases using slow-absorbing sutures and medium clips, SLNs were identified and removed in all cases. Overall axillary staging was avoided in 62 DCIS lesions (79.5%). The authors conclude that for patients with DCIS undergoing mastectomy, intraoperative marking and preservation of SLNs using a simple and affordable technique can be an effective surgical strategy to minimize unnecessary axillary node staging.