Carcinoembryonic antigen is the preferred biomarker for in vivo colorectal cancer targeting
Menée sur des échantillons de tissu tumoral et de tissu sain prélevés sur 280 patients atteints d'un cancer colorectal, cette étude évalue la sensibilité et la spécificité de quatre biomarqueurs (CEA, TAG-72,
Background: Colorectal cancer-specific biomarkers have been used as molecular targets for fluorescent intra-operative imaging, targeted PET/MRI, and selective cytotoxic drug delivery yet the selection of biomarkers used is rarely evidence-based. We evaluated sensitivities and specificites of four of the most commonly used markers: carcinoembryonic antigen (CEA), tumour-associated glycoprotein-72 (TAG-72), folate receptor-
α (FRα) and endothelial growth factor receptor (EGFR).
Methods:
Marker expression was evaluated semi-quantitatively in matched mucosal and colorectal cancer tissues from 280 patients using immunohistochemistry (scores of 0
–15). Matched positive and negative lymph nodes from 18 patients were also examined.
Results: Markers were more highly expressed in tumour tissue than in matched normal tissue in 98.8%, 79.0%, 37.1% and 32.8% of cases for CEA, TAG-72, FR
α and EGFR, respectively. Carcinoembryonic antigen showed the greatest differential expression, with tumours scoring a mean of 10.8 points higher than normal tissues (95% CI 10.31
–11.21, P<0.001). Similarly, CEA showed the greatest differential expression between positive and negative lymph nodes. Receiver operating characteristic analyses showed CEA to have the best sensitivity (93.7%) and specificity (96.1%) for colorectal cancer detection.
Conclusion: Carcinoembryonic antigen has the greatest potential to allow highly specific tumour imaging and drug delivery; future translational research should aim to exploit this.
British Journal of Cancer , article en libre accès, 2012