Patterns of recurrence after sentinel lymph node biopsy for breast cancer

Background: Sentinel lymph node biopsy (SLNB) is gaining acceptance as an alternative to axillary lymph node dissection. The purpose of this study was to determine the frequency and pattern of disease recurrence after SLNB. Methods: Two-hundred twenty-two consecutive patients undergoing SLNB from April 6, 1998, to October 27, 1999, and who were ≥24 months out from their procedure were identified from a prospectively maintained database. Retrospective chart review and data analysis were performed to identify variables predictive of recurrence. Results: The median patient follow-up was 32 months (range, 24-43 months). A total of 159 patients (72%) were sentinel lymph node (SLN) negative and had no further axillary treatment. Five of these patients (3.1%) developed a recurrence (one local and four distant), with no isolated regional (axillary) recurrences. Sixty-three patients (28%) were SLN positive and underwent a subsequent axillary lymph node dissection. Six of these patients (9.5%) developed a recurrence (three local, one regional, and two distant). Pathologic tumor size (P < .001), lymphovascular invasion (P = .018), and a positive SLN (P = .048) were all statistically significantly associated with disease recurrence. Conclusions: With a minimum follow-up of 24 months, patients with a negative SLN and no subsequent axillary treatment demonstrate a low frequency of disease recurrence. This supports the use of SLNB as the sole axillary staging procedure in SLN-negative patients.