title: The application of C12 biochip in the diagnosis and monitoring of colorectal cancer: systematic evaluation and suggestion for improvement.
abstract: BACKGROUND
  The 12 tumor markers' (TMs) biochip diagnostic (C12) system has been proven useful in some previous studies but its value for colorectal cancer (CRC) only was not systematically investigated.
  
  
  OBJECTIVE
  To evaluate the value of C12 system for CRC.
  
  
  METHODS
  The associations between TMs and clinicopathological characteristics were evaluated. The most relevant TMs, the most useful combinations, and the correlations between TM levels were assessed.
  
  
  METHODS
  The TMs detected by the C12 system in the sera of 170 pathologically confirmed CRC patients were analyzed. One or more TMs higher than or equal to reference value were defined as positive.
  
  
  METHODS
  Chi-square test, Spearman rank correlation test and Receiver-operating characteristic (ROC) curves were used for the analysis.
  
  
  RESULTS
  The overall positive rate was 41.76%, and was low in stage 0-I (12.90%). Carcinoembryonic cantigen (CEA) had the highest positive rate of 36.47%. The positive rates were significantly correlated to clinical stages and lymph node status, but not to age, sex, tumor location and pathological types. Any combinations of the five highest positive TMs did not have significantly improvements. The levels of three most related TMs (CEA, CA19-9, CA242) of CRC had positive correlation with each other. CA242 and beta-HCG levels were associated with lymph node metastasis.
  
  
  CONCLUSIONS
  C12 system has some value in advanced CRC, but not in early CRC.
authors.affiliation: Department of Oncology, Zhongnan Hospital of Wuhan University, Hubei Key Laboratory of Tumour Biological Behaviors and Hubei Cancer Clinical Study Center, Wuhan, 430 071, PR China.
authors.forename: C
authors.initials: C
authors.lastname: Chen
authors.forename: L Q
authors.initials: LQ
authors.lastname: Chen
authors.forename: G L
authors.initials: GL
authors.lastname: Yang
authors.forename: Y
authors.initials: Y
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000097:blood*; D019540:Area Under Curve; D014408:Biomarkers, Tumor / Q000097:blood*; D018395:CA-19-9 Antigen / Q000097:blood*; D002272:Carcinoembryonic Antigen / Q000097:blood*; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D011237:Predictive Value of Tests; D040081:Protein Array Analysis; D012372:ROC Curve; D055815:Young Adult
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate; D014408:Biomarkers, Tumor; C074601:CA 242 antigen; D018395:CA-19-9 Antigen; D002272:Carcinoembryonic Antigen