Fluorescence imaging at the macroscaleis subjectedto the diffusenature of photons and may obscure the true specificity of FGS agentsthat target a tumor biomarker (e.g., a receptor).27 Thus, we examined the correlation between fluorescenceand SSTR2 distribution using mesoscopic NIRF imaging and immunohistopathology.In tumors, we found that only MMC(FNIR-Tag)-TOC had a fluorescencelocalization pattern that was consistent with IHC staining (Figure 2F). This evidence concerns the gene SSTR2 and neoplasm.