Fluorescence Imaging-Assessed Surgical Margin Detection in Head and Neck Oncology by Passive and Active Targeting.

Surgery remains the gold standard in the management of head and neck squamous cell carcinoma (HNSCC). However, the anatomical complexity of these cancers, combined with the difficulty in discriminating between healthy and cancerous tissue and the detection of microlesions, complicates tumor resection, resulting in positive surgical margins, which are associated with a poor patient prognosis. Fluorescence-guided surgery (FGS) has emerged as a promising technique in the management of HNSCC, improving tumor resection and margin assessment. FGS strategies can be roughly divided into three approaches; namely, natural tissue autofluorescence, passive delivery of fluorescent contrast agents, and active targeting. This review provides a comprehensive overview of the advances made in FGS of head and neck cancers, particularly aiming to improve surgical margin assessment. Recently, the field has shown promising results by addressing contrast agents targeted to the overexpressed epidermal growth factor receptor (EGFR), both in preclinical and clinical settings. The identification of new targets such as αVβ6 integrin, uPAR, PARP1, and so on, as well as the development of contrast agents, are key steps in the further development of FGS of head and neck cancers, making it an essential tool in precision oncology. Among these, as was demonstrated in preclinical studies, the αVβ6 integrin is emerging as a promising target due to its high and specific expression in tumor and tumor margins.