# The New Kid on the Block: Validating the Role of Indocyanine Green for Sentinel Lymph Node Biopsy in the Post-neoadjuvant Setting in Patients With Breast Cancer

## TL;DR

This study validates indocyanine green's effectiveness for sentinel lymph node biopsy in breast cancer patients after chemotherapy, particularly in the Indian population.

## Contribution

The study provides new evidence on the accuracy and safety of indocyanine green in sentinel lymph node biopsy post-neoadjuvant chemotherapy in breast cancer.

## Key findings

- ICG showed a 100% identification rate and 96.67% accuracy in sentinel lymph node biopsy.
- The false negative rate was 5.55% with no allergic reactions or skin necrosis observed.
- ICG fluorescence imaging allows real-time visualization and reduces reliance on nuclear medicine infrastructure.

## Abstract

Background and objective

There is scarce literature on the role of indocyanine green (ICG) in sentinel lymph node biopsy (SLNB) post-neoadjuvant chemotherapy (NACT) in breast cancer patients, specifically in the Indian population. This study aimed to address this gap by evaluating the identification rates and accuracy of SLNB using ICG.

Methods

A prospective observational study was conducted over 18 months at Vardhman Mahavir Medical College, New Delhi, involving 30 patients with locally advanced breast cancer. The primary objectives were identification rates, positive predictive value, and false negatives. All patients underwent SLNB post-NACT and, irrespective of SLNB results, underwent axillary lymph node dissection (ALND). The secondary objectives of the study focused on complications related to ICG dye.

Results

The mean age of the cohort was 44.83 years. The SLNB technique using ICG showed an identification rate of 100% with a sensitivity of 91.67%, a specificity of 100% with a false negative rate of 5.55%, and an accuracy of 96.67%. No cases of allergic reactions to ICG or skin necrosis were observed.

Conclusions

Our findings validate the use of ICG dye for SLNB in neoadjuvant setting for patients with breast cancer, demonstrating high sensitivity and specificity. ICG fluorescence imaging permits real-time visualization of lymphatics for SLNB and, at the same time, minimizes complications and high-tech nuclear medicine infrastructure requirements.