# Evaluating the Use and Feasibility of Indocyanine Green (ICG) as a Beacon of Precision in Sentinel Node Biopsy for Breast Cancer from an Oncoplastic Practice in India

## TL;DR

This study shows that indocyanine green (ICG) is a safe and effective alternative to radioactive tracers for sentinel node biopsy in breast cancer, especially in resource-limited settings like India.

## Contribution

The study presents the largest Indian cohort evaluating ICG for sentinel lymph node biopsy and demonstrates its high accuracy and feasibility in low-resource settings.

## Key findings

- ICG achieved a 100% identification rate in upfront surgeries when used alone.
- ICG had comparable or better accuracy than traditional tracers, with low false-negative rates.
- ICG is a practical alternative in resource-limited settings due to its non-radioactive nature and favorable oncological outcomes.

## Abstract

Accurate staging of the axillary lymph nodes is essential for guiding treatment in breast cancer. Sentinel lymph node biopsy (SLNB) is the standard method for evaluating lymph node involvement and traditionally uses radioactive tracers combined with blue dye. However, this approach requires access to nuclear medicine facilities, which are often limited in many low- and middle-income countries (LMICs). In this study, we analyzed outcomes from 678 breast cancer patients treated at an oncoplastic breast surgery unit in India over a 10-year period, representing the largest reported Indian cohort evaluating indocyanine green (ICG) for SLNB. Our findings show that ICG demonstrated identification rates and accuracy comparable to or better than conventional tracers, with excellent node retrieval and very low false-negative rates, both in upfront surgery and after neoadjuvant therapy. When used alone, ICG achieved a 100% identification rate in upfront cases. Overall oncological outcomes, including recurrence rates, were favorable. In addition to being effective, ICG simplifies surgical logistics because it does not require radioactive tracers, making it particularly suitable for resource-limited settings. These results support ICG as a safe, practical, and scalable alternative for sentinel node mapping in breast cancer surgery.

Background: Accurate axillary staging is vital in breast cancer. While dual tracers (Tc-99m + methylene blue dye) are standard for sentinel lymph node biopsy (SLNB), indocyanine green (ICG) offers a cost-effective, safe alternative, especially where nuclear medicine access is limited. Despite growing global use, data from low- and middle-income countries (LMICs) remain scarce. This study presents India’s largest cohort using ICG in SLNB. Methods: We analyzed data from 678 breast cancer patients (2013–2023), of whom 609 underwent SLNB. For analysis, patients were grouped into: isotope + blue dye (control), ICG + blue dye (study group), and ICG alone. False-negative rate (FNR) was evaluated in cases where SLNB was followed by axillary lymph node dissection (ALND). All other outcomes were assessed across the SLNB cohort. Results: In upfront surgery, the study group had an identification rate (IR) of 95.6%, an FNR of 5%, and a median node yield of four, compared to the control group (IR 94.1%, FNR 0%, median of three). Post-neoadjuvant systemic therapy (NAST), the study group outperformed the control (IR 92% vs. 88.2%; both FNR 10%), with higher node yield (three vs. two). From 2021, ICG alone showed 100% IR, 0% FNR (upfront), and 95.6% IR (post-NACT), with high median node retrieval. Overall recurrence was 7.8%; loco-regional recurrence was 3.09%. Conclusions: ICG offers high efficacy, safety, and feasibility as a sole tracer, especially in LMICs. Its integration into SLNB and oncoplastic workflows supports its broader adoption as a practical alternative to radioisotopes in breast cancer surgery.