Incidence of axillary recurrence in 344 sentinel node negative breast cancer patients after intermediate follow-up. A prospective study into the accuracy of sentinel node biopsy in breast cancer patients.

Sentinel lymph node biopsy (SLNB) has been validated in the treatment of breast carcinoma and is considered to stage the axilla adequately in this disease. However, long-term follow-up data are scarce. We evaluated the results of SLNB with respect to loco-regional failures in the axilla in SN-negative patients with invasive breast carcinoma and analysed their causal factors. Between 1997 and May 2004, 656 patients without clinically palpable lymph nodes were included in our study. Data with regard to demographics, diagnostics, therapy and follow up were gathered prospectively from all patients. Patients treated after May 2004 were excluded from this study to permit at least one year of follow-up. Out of the 656 patients, 344 patients with a negative sentinel lymph node biopsy did not undergo axillary dissection and were followed up clinically. Median follow up was 43 months. In 3 patients (0.9%) axillary recurrences developed. All three patients subsequently underwent a completion axillary dissection, chemotherapy and radiotherapy. The low rate of clinical axillary recurrence after an intermediate follow up period suggests that a negative SN biopsy accurately reflects the nodal stage in patients with breast cancer.