CEACAM5 and neoplasm: More recently, anti-CEA Nbs, conjugated with the near-infrared dye IRDye800CW, were successfully used for FGS in an orthotopic transplanted model of pancreatic cancer [86]: fluorescent anti-CEA Nbs rapidly and precisely accumulated in tumor tissue, showing a labeling kinetic that was similar to the one of non-specific tracers, such as indocyanine green.