Axillary metastases in breast cancer patients with negative sentinel nodes : a follow-up of 3548 cases

Premises: Sentinel node biopsy (SNB) in patients with breast carcinoma accurately predicts the axillary node status. However, in some 4-7% of patients with negative sentinel nodes, the remaining axillary nodes harbour cancer cells. Objective: Our purpose was the long-term observation of a large number of patients who did not receive axillary dissection after a negative sentinel node biopsy, in order to evaluate the incidence of overt axillary metastases. Methods: Patients (3548) treated from 1996 to 2004, with negative sentinel nodes not submitted to axillary dissection, were followed up to 11 years with a median follow-up of 48 months. Results: Three hundred and sixteen unfavourable events occurred among the 3548 patients, 196 of which (5.5%) related to primary breast carcinoma. Thirty one cases of overt axillary metastases were found (0.9%): they received total axillary dissection and 27 of them are at present alive and well. The 5-year overall survival rate of the whole series was 98%. Conclusions: Patients with negative sentinel node biopsy not submitted to axillary dissection show, at follow-up, a rate of overt axillary metastases lower than expected.