Second biopsy of axillary sentinel lymph node for reappearing breast cancer after previous sentinel lymph node biopsy

Background: Sentinel lymph node biopsy (SLNB) is a safe and accurate axillary staging procedure for patients with primary operable breast cancer. An increasing proportion of these patients undergo breast-conserving surgery, and 5% to 15% will develop local relapses that necessitate reoperation. Although a previous SLNB is often considered a contraindication for a subsequent SLNB, few data support this concern. Methods: Between January 2000 and June 2004, 79 patients who were previously treated at our institution with breast-conserving surgery and who had a negative SLNB for early breast cancer developed, during follow-up, local recurrence that was amenable to reoperation. Eighteen of these patients were offered a second SLNB because of a clinically negative axillary status an average of 26.1 months after the primary event. Results: In all 18 patients (7 with ductal carcinoma-in-situ and 11 with invasive recurrences), preoperative lymphoscintigraphy showed an axillary sentinel lymph node, with a preoperative identification rate of 100%, and 1 or more SLNs (an average of 1.3 per patient) were surgically removed. Sentinel lymph node metastases were detected in two patients with invasive recurrence, and a complete axillary dissection followed. At a median follow up of 12.7 months, no axillary recurrences have occurred in patients who did not undergo axillary dissection. Conclusions: Second SLNB after previous SLNB is technically feasible and likely effective in selected breast cancer patients. A larger population and longer follow-up are necessary to confirm these preliminary data.