Accuracy of Methylene Blue Test as Single Technique for Sentinel Lymph Node Biopsy in Early Stages Breast Cancer

Aim: Sentinel Lymph Node Biopsy (SLNB) establishes as a gold standard for diagnostic lymph node involvement in early breast cancer. Most of the developed country does not have radiotracer and nuclear medicine facilities. Unless in Indonesia there is Methylene Blue as an alternative agent for SLNB. This study measure accuracy of sentinel lymph node biopsy as a single technique using the Methylene Blue test. Methods: This cross-sectional study enrolled 60 female patients with breast cancer stage I-II. We performed SNB using 2-5 cc of 1% Methylene-blue dye (MBD) injected to periareolar tissue and proceeded with axillary lymph nodes dissection (ALND). The histopathology results of sentinel nodes (SNs) and axillary lymph nodes (ALNs) analyze for diagnostic value assessments. Results: The identification rate of SN was 97.62 %, and the median number of identified SNs was 4 (2-7). Sentinel node metastasis was found in (19/60) % cases and % of them were macrometastases. The sensitivity and specificity of MBD were 91.67% and 96.67% respectively. The negative predictive value (NPV) of SNs to predict axillary metastasis was 96.67% (95% CI, 81-99%). Conclusion: Injection of 1% MBD as a single technique in breast cancer SNB has a favorable identification rate and predictive value.