Localization of the sentinel lymph node in breast cancer: prospective comparison of vital staining and radioactive tracing methods.

The aim of the study was to evaluate possible differences in accuracy between the radioactive tracing and vital staining method in the search for sentinel nodes in patients with breast cancer. From January 1999 to December 2000, 102 patients with T1 N0 breast carcinoma were recruited into the study for localization of sentinel nodes with vital blue dye staining and radioactive tracing and were then submitted to lumpectomy and axillary dissection. For the two methods, we estimated the percentage of sentinel nodes localized, the false-negative rate, the predictive negative and positive value and the accuracy. The vital blue dye staining method permitted localization of the sentinel node in 73% of patients with a false-negative rate of 8%, a predictive negative value of 92% and 92% accuracy. The radioactive tracing method permitted localization of the sentinel node in 97% cases with a false-negative rate of 0%, a predictive negative value of 100% and 100% accuracy (P<0.0005). The method that offers the better results is radioactive tracing. Currently, many authors use both techniques, since, in common practice, staining helps to identify the sentinel node with the probe.