Sentinel lymph node biopsy in breast cancer: Validation study and comparison of lymphatic mapping techniques

Abstract

Introduction: Sentinel lymph node biopsy is a standard staging procedure in patients with early breast cancer. Aim of the study is a validation procedure of sentinel lymph node biopsy (SLNB) in our institution and comparison between two mapping techniques - isotope mapping and methylene blue dye for lymphatic mapping. Material and methods: The study comprised 75 women with breast cancer of clinical stage T1-2N0M0. We analyzed patients from June, 2010 to March, 2013. In 39 patients, (Group A) lymphatic mapping technique was performed by using the peritumoral injection of 37MBq activity isotope (99m Technetium NANOCIS),and in 36 patients (Group B) mapping technique was performed by using the periareolar injection of 2-4 ml blue dye (Methylene blue 1%). Axillary dissection was performed in both groups after SLNB. Results: Out of 75 patients, sentinel lymph node was identified in 68 (90.7%). Identification rate was similar between the groups - 89.7% (Group A), 91.7% (Group B). Accuracy rate was 97% between the groups, that is, Group A 97.1% and Group B 96.9%. In relation to the Group A (90.6%), sensitivity rate was slightly higher in the Group B - 91.6%,. False negative rate of SLNB was higher in the Group A (9.1%) in relation to the Group B (8.3%). The average number of sentinel nodes detected in both groups was 1.2. Conclusion: The results of the study confirmed and validated both methods of lymphatic mapping techniques in SLNB. There were no significant statistical differences (p>0.05) in accuracy, sensitivity and false negative rate between these two groups.

Keywords

• breast cancer
• sentinel lymph node biopsy
• isotope
• blue dye