Reliability of sentinel node status in predicting axillary lymph node involvement in breast cancer

Objectives: To assess the reliability of determining sentinel node status i n staging regional lymph nodes in breast cancer. Design and setting: Prospective validation study in a major public teaching hospital, comparing histological sentinel node status with that of remaini ng axillary nodes. Patients: 117 women who underwent sentinel node biopsy and axillary dissect ion for primary breast cancer between 1995 and 1998. Main outcome measures: Intraoperative success rate in sentinel node identif ication; false negative rate; predictive value of negative sentinel node st atus; overall accuracy of sentinel node status. Results: The sentinel node was identified at operation in 95 patients (81.2 %). Tumour involvement of the sentinel node was demonstrated in 29 of 31 wo men (93.5%; 95% CI, 79%-99%). Sixty-four Of the 66 women in whom the sentin el node was negative for tumour showed no further involvement of remaining axillary nodes (standard haematoxylin-eosin histological assessment), givin g a predictive value of negative sentinel node status of 97% (95% CI, 89%-1 00%). The overall accuracy in 95 women in whom sentinel node status was com pared with axillary node status was 97.9%. Conclusions: Histopathological examination of the sentinel node is an accur ate method of assessing axillary lymph node status in primary breast cancer and is likely to be incorporated into future surgical management of women with primary breast cancer.