Sentinel lymph node biopsy as an indicator for axillary dissection in early breast cancer.

Sentinel node biopsy (SNB) is a new component of the surgical treatment of breast cancer that accurately predicts axillary status. Although the procedure is still mainly investigational, many patients are requesting SNB to avoid axillary dissection if the sentinel node (SN) is negative. From March 1996 to December 1999, 373 patients with breast carcinoma and clinically negative axillary nodes underwent breast surgery, mainly conservative, and SNB. If the SN was histologically uninvolved no further surgical treatment was given. All patients were informed in detail and signed a consent form. SNB involved injection of labelled albumin particles close to the primary tumour, lymphoscintigraphy and location of the sentinel node with a gamma probe during surgery. 379 SNBs were performed on 373 patients (6 were bilateral). In 94, the SN was positive and complete axillary dissection was performed. In 285 cases (280 patients) the SN was negative and no dissection was performed: these were carefully followed with quarterly clinical examination of the axilla. A total of 343 years at risk were available for evaluation from which seven cases of axillary metastases were expected. No cases of clinically evident axillary node metastasis have occurred. These findings provide further confirmation of the validity of SNB and prompt us to suggest that it should become the method of choice for axillary staging in small-sized breast cancer.