Tumor pyruvate kinase isoenzyme type M2 and immunochemical fecal occult blood test: performance in screening for colorectal cancer.
OBJECTIVE
Immunochemical fecal occult blood test (FOBT) and determination of tumor pyruvate kinase isoenzyme type M2 (TuM2-PK) in stool samples may be valuable new screening tools for colorectal cancer (CRC). The aim of this study was to compare the accuracy of fecal TuM2-PK testing with immunochemical FOBT in patients with CRC or adenomas.


METHODS
A total of 52 patients with CRC were analyzed, 47 with colorectal adenomas, and 63 matched controls with a normal colonoscopy. Nineteen additional patients with inflammatory bowel disease were tested to determine influence of inflammation. Stool samples were analyzed with two immunochemical FOBTs, Immo-care and OC-Light, and with a commercial enzyme-linked immunosorbent assay for TuM2-PK.


RESULTS
In patients with CRC, the sensitivity of TuM2-PK, Immo-care and OC-Light was respectively 85, 92 and 94%. In patients with adenomas, the sensitivity was respectively 28, 40 and 34%. Specificity for these tests was 90% for TuM2-PK and 97% for both immunochemical FOBTs. All tests showed a high positivity rate in patients with inflammatory bowel disease (79% for TuM2-PK and Immo-care, and 89% for OC-Light).


CONCLUSIONS
Both immunochemical FOBTs appear valuable and are sensitive tests for CRC screening. TuM2-PK does not have supplemental value for screening for CRC because of a lower sensitivity and specificity. None of these tests is sensitive enough for detection of advanced adenomas. Patients with inflammatory bowel disease should be excluded from CRC screening when using immunochemical FOBT or TuM2-PK.
Mulder
Sanna A
SA
Department of Gastroenterology, Ikazia Ziekenhuis, Montessoriweg 1, Erasmus Medical Center, Dr Molewaterplein 40, Rotterdam, The Netherlands. S.mulder.1@erasmusmc.nl
van Leerdam
Monique E
ME
van Vuuren
Anneke J
AJ
Francke
Jan
J
van Toorenenbergen
Albert W
AW
Kuipers
Ernst J
EJ
Ouwendijk
Rob J Th
RJ
D000236:Adenoma / Q000175:diagnosis; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D002352:Carrier Proteins / Q000032:analysis*; D004796:Clinical Enzyme Tests / Q000379:methods; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D004812:Epidemiologic Methods; D005189:False Positive Reactions; D005243:Feces / Q000737:chemistry; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000201:enzymology; D008297:Male; D008565:Membrane Proteins / Q000032:analysis*; D008875:Middle Aged; D009780:Occult Blood; D011770:Pyruvate Kinase / Q000032:analysis*; D013963:Thyroid Hormones / Q000032:analysis*; D000097810:Thyroid Hormone-Binding Proteins
D014408:Biomarkers, Tumor; D002352:Carrier Proteins; D008565:Membrane Proteins; D011770:Pyruvate Kinase; D013963:Thyroid Hormones; D000097810:Thyroid Hormone-Binding Proteins