Effect of the use of vital dye, lymphoscintigraphy, or a combination for axillary lymphatic mapping and sentinel node biopsy in breast cancer.

Axillary dissection in patients with breast cancer is associated with significant morbidity. Because 85% of the patients with a cancer < or = 1 cm have negative axillary nodal status, axillary dissection in these patients is only a staging procedure. A study of the sentinel lymph node (SLN) biopsy has been developed to determine axillary nodal status by means of a minimally invasive procedure. The aim of our study was to estimate the degree of reliability for identifying the SLN using a vital dye or lymphoscintigraphy, or a combination of the two. From January 1999 to May 2000 a series of 60 patients with breast cancer were evaluated for enrollment in the study. For the mapping procedure, lymphoscintigraphy in combination with injection of vital blue dye was performed in 24 patients, and vital dye alone was utilized in 36. Complete axillary dissection was performed in all patients after SLN biopsy. The mapping procedure was possible in 59 cases (98.3%). The SLNs were positive in 19 patients (32.2%) and negative in 40; in 38 of the 40 patients all axillary nodes were negative. There was concordance in 57 of 59 cases (96.6%). The false-negative rate was 5% (2/40). The overall sensitivity of the SLN biopsy was 90.4% (19/21), with a negative predictive value of 95% (38/40). Our results indicate that SLN biopsy guided by a gamma probe in combination with vital dye can identify a negative axilla with high accuracy. We conclude that the use of both techniques produces an optimal result, as they are complementary.