EGFR and colorectal carcinoma: Further to the validation of FRES/F-SERS endoscopy of EGFR/HER2, and once again in CRC, we validated the duplex targeting capability, the system’s detection limit (sensitivity) and reproducibility, and also its capacity for quantification and real-time imaging using F-SERS dots for EGFR (the target of cetuximab) and VEGF (the target of bevacizumab).