Background/aims: Gastrointestinal (GI) cancer remains number one cancer killer in China. Serum tumor markers (TMs) are frequently used in the diagnosis of GI cancer. This study was to assess value of C12 multi-tumor marker protein chip diagnostic system developed in China in GI cancer.
Methodology: Sera from 329 GI cancer patients were detected by the C12 protein chip diagnostic system which consisted of 12 TMs including CEA, AFP, CA19-9, CA242, CA15-3, CA125, PSA, fPSA, NSE, B-HCG, HGH and Ferritin. The contribution of various TMs to the improvement of diagnosis was analyzed. The relationship between its positive rate and clinical stage, pathological type, and gender were explored.
Results: The diagnostic rates were 13.73%, 33.33%, 38.30%, 58.03%, respectively, for stage I, II, III and IV patients, and the overall diagnostic rate was 39.21%. There were statistically significant differences in stage I versus stage III, stage I versus stage IV, and stage II versus stage IV (p < 0.01). The other stage comparisons did not reach statistical significance (p > 0.05). Among the 12 TMs of the protein chip, the top 3 positive rates of 27.36%, 19.76% and 19.45% were obtained from CEA, CA242 and CA19-9, respectively, which were correlated with stage of GI cancer. The combinations of 5 most relevant TMs (3, 4 or 5 markers combined) improve the diagnostic rate significantly comparison to CEA (p < 0.05 or p < 0.01)). The combination of CEA+CA19-9+f-PSA (35.71%) for male patients, and CEA+CA19-9+ CA125 (40.95%) for female patients almost got the same diagnostic value as the C12 protein chip diagnostic system did (38.39% for male, 40.95% for female).
Conclusions: The C12 system is of some value in the diagnosis of GI cancer, but new markers are needed to improve the early diagnosis. In GI cancer, the most rational combination way was CEA+CA19-9+f-PSA for male patient and CEA+CA19-9 +CA125 for female patient.