Diagnosis and monitoring of colorectal cancer by L6 blood serum polymerase chain reaction is superior to carcinoembryonic antigen-enzyme-linked immunosorbent assay.
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.
Schiedeck
Thomas H K
TH
Department of Surgery, University Hospital Luebeck, Germany.
Wellm
Carsten
C
Roblick
Uwe J
UJ
Broll
Rainer
R
Bruch
Hans-Peter
HP
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
D000954:Antigens, Surface; D002272:Carcinoembryonic Antigen; D009363:Neoplasm Proteins; D012333:RNA, Messenger; C074075:TM4SF1 protein, human