The use of radioisotope combined with isosulfan blue dye is not superior to radioisotope alone for the identification of sentinel lymph nodes in patients with breast cancer

Background Isosulfan Blue dye (BD) allergic drug reactions (ADR) occur in up to 2% of patients undergoing SLN biopsy (SLNB). We sought to determine if BD enhances the performance of SLNB such that this risk is justified. Methods A retrospective review of 392 breast cancer patients undergoing SLNB between 8/99 and 8/04 was performed; 208 patients had radioisotope (ISO) alone, 167 had ISO+BD. Total SLN and positive SLN in each group were compared. We examined the ISO+BD group for concordance and the presence of blue only nodes. The effect of tumor location, injection site, angiolymphatic invasion, Her2/neu expression, and the presence of a noninvasive component were studied. Chi-square, linear regression, Fisher t tests, and ANOVA were performed. Results SLN were identified in 94% of ISO and 96% of ISO+BD patients. The mean number SLN from the ISO group was 2.01, 1.93 for ISO+BD; 27% of ISO and 21% of ISO+BD patients had positive nodes. These differences were not significant. No difference for tumor location, injection site, angiolymphatic invasion, Her2/neu expression, or the presence of a noninvasive component was found. Conclusion The addition of BD to ISO in patients with invasive breast cancer does not significantly enhance the performance of SLNB.