title: Diagnosis and monitoring of colorectal cancer by L6 blood serum polymerase chain reaction is superior to carcinoembryonic antigen-enzyme-linked immunosorbent assay.
abstract: OBJECTIVE
  The aim of this study was to compare carcinoembryonic antigen levels with detection of messenger ribonucleic acid coding for the tumor-associated antigen L6 in patients with colorectal cancer. Not only are carcinoembryonic antigens expressed by the corresponding tumor cell, but the messenger ribonucleic acid of tumor-associated antigens, in contrast, is produced exclusively by viable tumor cells.
  
  
  METHODS
  L6 messenger ribonucleic acid was determined by reverse-transcription polymerase chain reaction. Carcinoembryonic antigen was measured by the enzyme-linked immunosorbent assay technique, with a cutoff value of 40 microg/l. Blood serum was sampled from 187 patients with colorectal cancer. Statistical significance was calculated with the McNemar chi-squared test.
  
  
  RESULTS
  Preoperatively, 79 percent of patients in all stages were positive for L6 messenger ribonucleic acid, whereas only 35 percent had elevated carcinoembryonic antigen titers (P < 0.001). In Dukes A tumors, 84.9 percent of patients were positive for L6 messenger ribonucleic acid, whereas carcinoembryonic antigen was elevated in only 16.9 percent of patients. Only in Dukes D tumors did the enzyme-linked immunosorbent assay for carcinoembryonic antigen exhibit the same sensitivity as reverse-transcription polymerase chain reaction for L6 messenger ribonucleic acid. Recurrence was detected significantly earlier by reverse-transcription polymerase chain reaction for L6 messenger ribonucleic acid than by enzyme-linked immunosorbent assay for carcinoembryonic antigen.
  
  
  CONCLUSIONS
  L6 is more sensitive and precise than carcinoembryonic antigen in diagnosing and monitoring colorectal cancer.
authors.affiliation: Department of Surgery, University Hospital Luebeck, Germany.
authors.forename: Thomas H K
authors.initials: TH
authors.lastname: Schiedeck
authors.forename: Carsten
authors.initials: C
authors.lastname: Wellm
authors.forename: Uwe J
authors.initials: UJ
authors.lastname: Roblick
authors.forename: Rainer
authors.initials: R
authors.lastname: Broll
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Bruch
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000954:Antigens, Surface / Q000097:blood*; D002272:Carcinoembryonic Antigen / Q000097:blood*; D016009:Chi-Square Distribution; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000097:blood*; D009367:Neoplasm Staging; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000097:blood; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D000954:Antigens, Surface; D002272:Carcinoembryonic Antigen; D009363:Neoplasm Proteins; D012333:RNA, Messenger; C074075:TM4SF1 protein, human