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

Background Near-infrared fluorescence–guided surgery (FGS), predominantly using indocyanine green (ICG), is increasingly adopted to support intraoperative decision-making in colorectal cancer (CRC). This narrative review synthesizes current evidence across four major clinical applications—assessment of anastomotic perfusion, lymphatic mapping, tumor localization, and metastasis detection—and outlines translational directions (targeted probes, multimodality, quantitative analytics/AI). Methods: We conducted a narrative, non-systematic review of clinical and translational studies on intraoperative fluorescence imaging in CRC, with a primary focus on ICG-based techniques and emerging targeted agents. Representative studies were selected to illustrate benefits, technical constraints (dose, timing, optics), and methodological limitations; formal risk-of-bias assessment and meta-analysis were not performed given the heterogeneity of designs. Results: (1) Anastomotic perfusion: ICG fluorescence angiography reduces uncertainty regarding transection lines and tissue viability; impact on anastomotic leak appears protocol-dependent and is likely enhanced by standardized acquisition parameters and objective, real-time quantification. (2) Lymphatic mapping: ICG improves visualization of drainage pathways and nodal basins but does not discriminate benign from metastatic involvement; the utility is primarily anatomic/functional. (3) Tumor localization: FGS facilitates identification of lesions and margins in selected scenarios; non-contrast adjuncts (e.g., hyperspectral imaging) may complement perfusion assessment. (4) Metastases: In the liver, FGS is useful as a rule-out tool and for margin guidance; in peritoneal disease, targeted anti-CEA approaches integrated with multimodality workflows (NIR + SPECT/CT + gamma-probe) demonstrate feasibility and clinical promise. Conclusions: ICG-based FGS is sufficiently mature for selective use in CRC—most notably for anastomotic perfusion assessment and resection guidance. Broader adoption will require protocol standardization, robust real-time quantification, and multicenter validation of targeted probes with clinically meaningful endpoints.