Clinical fluorescent probes: mechanisms, advantages and inspirations

Fluorescence imaging is revolutionizing oncologic surgery by overcoming the limitations of visual and tactile guidance. Despite this promise, clinical translation remains limited, with only a handful of probes having received regulatory approval. Using a challenges-strategy-efficacy-comparison framework, this review outlines clinical probes used across six major organ systems (nervous, circulatory, respiratory, digestive, reproductive, and urinary), including (1) clinical surgical challenges for probe design: tumor heterogeneity, occult margins, and deep-seated lesions; (2) strategies and mechanisms: spanning ligand targeting, specific activatable chemistries, deep-penetration molecular scaffolds, and theranostic integration; (3) clinical quantitative efficacy metrics: differentiated distinction, excellent biosafety, high signal-to-noise ratio, and operational compatibility, and (4) functional extension of probes beyond resection. Moreover, a comprehensive comparative analysis between clinical and non-clinical probes is conducted to highlight the gaps and challenges between them, whereby the insights from the advantages of clinical probes are discussed to inspire the development of next-generation fluorescent probes. Based on data from a large number of clinical trials and surgeon requirements, this review highlights the crucial role of fluorescent probes in tumor removal, providing guidance to accelerate their clinical translation.