[Comparison of different stool tests for the detection of cancer of the colon].
OBJECTIVE
Colonoscopy is the gold standard for the diagnosis of colonic neoplasia. Because of the low compliance, the discomfort of bowel preparation and the procedure itself and the (albeit small) risk of perforation or bleeding alternative procedures such as stool tests are being focused on.


METHODS
After informed consent stool samples of 116 patients (44 male, 72 female, median age 47 years), scheduled for colonoscopy and 22 patients (17 m, 5 f, 69 y) with known colorectal cancer stool samples were collected. The samples were investigated by three methods: a biochemical (Guajak) test for fecal occult blood, an immunological test for fecal occult blood and a test determining the dimer pyruvat kinase M2 (tumor M2-PK).


RESULTS
Sensitivity for detection of colorectal cancer or polyps was 27 % and 10 % for the biochemical test, 91 % and 19 % for the immunological test and 77 % and 48 % for the M2-PK-test, respectively. Specificity was 89 %, 94 % and 72 %, respectively.


CONCLUSIONS
Both methods for detection of occult blood had a similar specificity. The sensitivity of the immunological test for the detection of colorectal cancer was significantly higher. The M2-PK-test had a markedly lower specificity in diagnosing cancer. Because of the low sensitivity for polyps the usefulness of stool tests is questionable. Reducing incidence and mortality of colorectal cancer should be achieved by colonoscopy, a recommendation that requires specific communication to the public.
Vogel
T
T
Abteilung Allgemein-, Viszeral- und Thoraxchirurgie, Kliniken Maria Hilf Mönchengladbach.
Driemel
C
C
Hauser
A
A
Hansmann
A
A
Lange
S
S
Jonas
M
M
Möslein
G
G
D000368:Aged; D001669:Biochemical Phenomena; D001671:Biochemistry; D014408:Biomarkers, Tumor / Q000032:analysis*; D003111:Colonic Polyps / Q000175:diagnosis; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D016001:Confidence Intervals; D005243:Feces / Q000201:enzymology*; D005260:Female; D006138:Guaiac; D006801:Humans; D007159:Immunologic Tests; D007202:Indicators and Reagents; D007258:Informed Consent; D008297:Male; D008875:Middle Aged; D009780:Occult Blood; D011770:Pyruvate Kinase / Q000032:analysis*; D012372:ROC Curve; D012680:Sensitivity and Specificity
D014408:Biomarkers, Tumor; D007202:Indicators and Reagents; D006138:Guaiac; D011770:Pyruvate Kinase