Is SLN Biopsy Alone Safe in SLN Positive Breast Cancer Patients?

The Z0011 trial demonstrated no difference in overall survival (OS) and locoregional recurrence in breast cancer patients with a positive sentinel lymph node (SLN) randomized to axillary lymph node dissection (ALND) or no further surgery. The aim of this study was to evaluate locoregional recurrence in a nonrandomized group of SLN positive patients, in whom cALND was not performed, that were retrospectively categorized by the Z0011 eligibility criteria. From two hospital breast cancer databases consisting of 656 consecutive SLN positive breast cancer patients, 88 patients, who did not undergo cALND, were identified. This population was categorized by the Z0011 inclusion criteria (e.g., eligible versus ineligible) and the groups were compared. Thirty-four patients (38.6%) were retrospectively eligible for omitting cALND according to the Z0011 criteria and 54 (61.4%) were not. The median number of SLNs removed in both groups was 1 (range 1-5). The number of positive SLNs did not differ between the groups. Tumor size was slightly larger in the ineligible group (21 mm versus 19 mm) and 76% of patients in the ineligible group underwent a mastectomy. At a median follow-up of 26 months (range 1-84 months), one axillary recurrence was observed in the ineligible group versus 0 in the eligible group. Axillary recurrence was low, even in patients who did not meet the Z0011 inclusion criteria. Future trials that randomize Z0011 ineligible patients are needed to investigate long-term results.