Abstract
Colorectal cancer (CRC) is the second-leading cause of cancer-related mortality worldwide, which may be effectively reduced by early screening. Colon cancer secreted protein-2 (CCSP-2) is a promising blood marker for CRC. An electric-field effect colorectal sensor (E-FECS), an ion-sensitive field-effect transistor under dual gate operation with nanostructure is developed, to quantify CCSP-2 directly from patient blood samples. The sensing performance of the E-FECS is verified in 7 controls and 7 CRC samples, and it is clinically validated on 30 controls, 30 advanced adenomas, and 81 CRC cases. The concentration of CCSP-2 is significantly higher in plasma samples from CRC and advanced adenoma compared with controls (both P < 0.001). Sensitivity and specificity for CRC versus controls are 44.4% and 86.7%, respectively (AUC of 0.67), and 43.3% and 86.7%, respectively, for advanced adenomas (AUC of 0.67). CCSP-2 detects a greater number of CRC cases than carcinoembryonic antigen does (45.6% vs 24.1%), and the combination of the two markers detects an even greater number of cases (53.2%). The E-FECS system successfully detects CCSP-2 in a wide range of samples including early stage cancers and advanced adenoma. CCSP-2 has potential for use as a blood-based biomarker for CRC.