# Fluorescence-Guided Surgery in Colorectal Cancer: State-of-the-Art and Translational Perspectives

## TL;DR

This review explores how fluorescence-guided surgery improves colorectal cancer operations, focusing on current uses and future needs for wider adoption.

## Contribution

The paper provides a comprehensive review linking clinical maturity to translational steps needed for routine adoption of fluorescence-guided surgery in colorectal cancer.

## Key findings

- ICG fluorescence angiography improves anastomotic perfusion assessment but its effect on leak prevention is protocol-dependent.
- ICG improves lymphatic mapping but cannot reliably distinguish benign from metastatic nodes.
- Targeted probes and multimodal approaches show promise for detecting peritoneal and hepatic metastases.

## Abstract

Fluorescence-guided surgery is increasingly used in colorectal cancer to improve real-time intraoperative visualization. Near-infrared imaging with indocyanine green is already applied to assess anastomotic perfusion and map lymphatic drainage, while newer tumor-targeted tracers are being developed for lesion identification, margin assessment, and detection of peritoneal and hepatic metastases. This review summarizes current evidence across these applications and highlights the main barriers to wider adoption, particularly protocol standardization, objective fluorescence quantification, and validation of targeted probes.

Background: Fluorescence-guided surgery based on near-infrared imaging, most often using indocyanine green (ICG), is increasingly used in colorectal cancer (CRC) surgery. This narrative review integrates current evidence across four clinically relevant domains-anastomotic perfusion, lymphatic mapping, tumor localization, and metastasis detection and emphasizes the technical and translational factors that will determine broader implementation. Methods: We performed a structured narrative review of clinical and translational studies identified through PubMed and citation tracking, with emphasis on ICG-based workflows and emerging targeted tracers. Because the literature spans heterogeneous interventions, imaging platforms, and endpoints, no de novo meta-analysis or formal risk-of-bias assessment was undertaken. Results: ICG fluorescence angiography is the most mature application and can refine transection-line selection, although its effect on anastomotic leak appears protocol dependent. In lymphatic mapping, ICG improves visualization of drainage pathways and nodal basins but does not reliably distinguish benign from metastatic nodes. For tumor localization, ICG supports lesion marking and dynamic tissue characterization, while targeted probes and contrast-free adjuncts may improve oncologic specificity. For metastatic disease, ICG is most useful for liver margin guidance and for excluding residual disease, whereas CEA-targeted and multimodal approaches appear particularly promising for peritoneal metastases. Conclusions: The added value of this review lies in linking current clinical maturity to the translational steps still required for routine adoption. In CRC surgery, fluorescence imaging is already useful in selected settings, but broader implementation will depend on standardized protocols, objective real-time quantification, and multicenter validation of targeted tracers against clinically meaningful outcomes.