title: Colorectal cancer detection in an asymptomatic population: fecal immunochemical test for hemoglobin vs. fecal M2-type pyruvate kinase.
abstract: BACKGROUND
  Screening programs for colorectal cancer (CRC) are mainly based on a first-line fecal immunochemical test for hemoglobin (FIT). Fecal M2-type pyruvate kinase (M2-PK) has been evaluated in clinical settings showing promising results for early CRC detection. However, the impact of fecal M2-PK assessment on the performance of first-round CRC screening programs is not known. We investigated whether fecal M2-PK alone or in combination with FIT may improve CRC screening efficacy in the general population.
  
  
  METHODS
  A total of 1027 asymptomatic subjects (median age 66 [59-74] years; females 504 [49.1%]), identified through the general practitioners' rosters, were invited for the collection of 2 fecal samples for FIT and M2-PK evaluation. Participants with at least positive one fecal test were referred for colonoscopy. Quality indicators for screening performance were calculated and analyzed using Fisher's exact test.
  
  
  RESULTS
  Overall, 572 subjects underwent both FIT and M2-PK assessment (participation rate 55.7%): 93 participants showed positive results for at least one test (positivity rate 16.3%). Only 10 patients were positive for both tests. Attendance rate to colonoscopy was 86.0% and a total of 65 adenomas and 7 cancers were detected. Combined use of FIT and fecal M2-PK permitted the identification of 18 more neoplasm (25%) without improving colonoscopy workload, as deduced by the comparable number needed to scope (P = 0.402).
  
  
  CONCLUSIONS
  The addition of M2-PK testing to FIT offers the potential to detect additional neoplasms that either do not bleed or only bleed intermittently without reducing participation rate and without increasing endoscopy workload.
authors.affiliation: Department of Medical Sciences, University of Turin, Turin, Italy.
authors.forename: Gian Paolo
authors.initials: GP
authors.lastname: Caviglia
authors.affiliation: Centro di Prevenzione Oncologica (CPO Piemonte), AOU Cittŕ della Salute e della Scienza, Turin, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Cabianca
authors.affiliation: Institute for Biostructures and Bioimages-CNR c/o Molecular Biotechnology Center, University of Turin, Turin, Italy.
authors.forename: Sharmila
authors.initials: S
authors.lastname: Fagoonee
authors.affiliation: Centro di Prevenzione Oncologica (CPO Piemonte), AOU Cittŕ della Salute e della Scienza, Turin, Italy.
authors.forename: Fabrizio M
authors.initials: FM
authors.lastname: Gili
mesh_terms: D000236:Adenoma / Q000175:diagnosis / Q000378:metabolism; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000378:metabolism; D005243:Feces / Q000737:chemistry* / Q000201:enzymology; D005260:Female; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D007120:Immunochemistry / Q000379:methods; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D009780:Occult Blood; D011770:Pyruvate Kinase / Q000378:metabolism*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; D006454:Hemoglobins; D011770:Pyruvate Kinase
keywords: M2-type pyruvate kinase; biomarker; colorectal cancer; occult blood; screening