Evaluation of feasibility and accuracy of sentinel node biopsy in early breast cancer

Current literature has suggested that sentinel node biopsy may eventually replace axillary dissection as the nodal staging procedure of choice in early breast cancer. The goals of our study were to determine the accuracy of the sentinel node in predicting axillary nodal status and to evaluate the feasibility of incorporating sentinel node biopsy into a general surgical practice.

Between June 1999 and August 2000, 158 clinically node negative women with a histological diagnosis of T1 or T2 breast cancer were enrolled in the study. Both technetium sulfur colloid radiotracer and isosulfan blue dye were used to guide sentinel node biopsy. Sentinel node biopsy was always followed by a complete axillary dissection. The histopathology of sentinel nodes using serial sectioning and cytokeratin immunohistochemistry was compared with that of the nonsentinel nodes evaluated with routine hematoxylin and eosin stain.

The overall sentinel node detection rate was 84% (89 of 106 patients). Sentinel node biopsy was most successful when a combination of radiotracer and dye was used. The staging accuracy of sentinel node biopsy was 98% (87 of 89); the sensitivity of the method was 94% (34 of 36); the false negative rate was 6% (2 of 36); the negative predictive value was 96% (53 of 55); and the rate of metastases to the sentinel node only was 56% (20 of 36). The results varied considerably among surgeons.

The findings in our study support the hypothesis that the sentinel node is an accurate predictor of axillary nodal status in women with early breast cancer. These results suggest that the excellent findings in the literature can be reproduced by a group of general surgeons in a community-based hospital.