Sentinel lymph node mapping in early breast cancer using methylene blue dye

Abstract

Background: With the introduction of the concept of sentinel lymph node biopsy (SLNB), the surgical management of the axilla has undergone a paradigm change in clinically node-negative early breast cancer, and complete axillary dissection is avoided if the sentinel lymph node (SLN) is negative for metastasis. Aim: The purpose of this study was to identify the reliability, accuracy, and safety of using methylene blue dye (MBD) in SLNB for early-stage carcinoma of the breast. Materials and Methods: A prospective study was conducted among 151 early breast carcinoma patients (T1/2N0M0) from December 2012 to February 2016. Intraoperative identification of the SLN was done by injecting 5 ml of 1% MBD into the subareolar region of the breast. All the blue-stained lymph nodes were then surgically excised and sent for frozen section examination. Results: The mean age of presentation was 54.10 years. Thirty out of 151 cases had SLN metastasis and 115 cases were negative for malignancy on the frozen section. On the final histopathological examination, 36 cases had metastasis and 115 cases were negative for malignancy. The false-negative rate was 5%. No patients developed anaphylactic/allergic or any type of skin reaction following MBD injection. The accuracy, positive predictive value, and negative predictive value of sentinel node identification using MBD were 96.02%, 100%, and 95.04%, respectively. After a mean follow-up of 10 months, no patient was found to be with ipsilateral axillary or supraclavicular recurrence. Conclusion: The use of MBD in SLNB for the diagnosis of axillary metastasis is reliable, accurate, and safe.