Value of tumor markers in diagnosing and monitoring colorectal cancer and strategies for further improvement: analysis of 130 cases

Measurement of blood tumor markers is the most widely used and convenient method for the diagnosis of colorectal cancer(CRC). This study was to evaluate the diagnostic value of a biochip diagnostic system C12 in the diagnosis of CRC.Twelve tumor markers were detected in the sera of 130 pathologically confirmed CRC patients, including carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), carbohydrate antigen 19-9 (CA19-9), carbohydrate antigen 242 (CA242), cancer antigen 15-3 (CA15-3), cancer antigen 125 (CA125), prostate specific antigen (PSA), free-PSA(f-PSA), neuron-specific enolase (NSE), human chorionic gonagotropin-beta (beta-HCG), human growth hormone (HGH), and ferritin, using the C12 diagnostic biochip system. The most relevant tumor markers and the most useful combinations of tumor markers were determined.The overall diagnostic rate for the 130 patients was 42.3%; and the diagnostic rates were 13.6%, 39.5%, 38.2% and 68.8%, for stages I, II, III and IV patients, respectively. There was significant difference in the diagnostic rates between stage I and stage IV patients. Among all the 12 markers, CEA had the highest diagnostic rate of 35.4%. Any combinations of the 5 most relevant tumor markers did not significantly improve the diagnostic rate. However, the combination of 4 markers (CEA+f-PSA +CA125+CA242 or CEA+CA19-9+CA125+f-PSA) was as good as 12 markers in terms of diagnosis.The C12 biochip diagnostic system has some value in the diagnosis of advanced CRC, but its sensitivity for the diagnosis of early CRC is not satisfactory.