title: Diagnostic performance of quantitative fecal immunochemical test and multivariate prediction model for colorectal neoplasms in asymptomatic individuals.
abstract: OBJECTIVE
  Quantitative fecal immunochemical test (QTFIT) has the advantage of being able to describe test characteristics on a scaled rather than binary system. The aims of this study were to decide the optimal cut-off points of QTFIT and to make a multivariate prediction model for colorectal neoplasms in asymptomatic adults.
  
  
  METHODS
  We retrospectively analyzed 1085 consecutive asymptomatic individuals who completed both full colonoscopy and QTFIT at a general health checkup clinic. Advanced adenomatous polyps (AP) were defined as APs of at least 1 cm in diameter; adenomas with villous component or high-grade dysplasia; and significant neoplasia (SN) including both advanced AP and colorectal cancer.
  
  
  RESULTS
  The ideal cut-off value of QTFIT was chosen based on a value that maximized the sum of both sensitivity and specificity, and clinical utility. For AP, 25 ng/ml was chosen as the optimal cut-off value and provided a sensitivity of 31% [95% confidence interval (CI): 27-36] and specificity of 79% (95% CI: 76-82). For SN, the ideal QTFIT cut-off value was 25 ng/ml, providing a sensitivity of 51% (95% CI: 39-62) and specificity of 77% (95% CI: 74-80). For colorectal cancer, the optimal cut-off point was 50 ng/ml, offering a sensitivity of 75% (95% CI: 41-93) and specificity of 86% (95% CI: 85-86). The multivariate prediction model was represented by nomogram and was validated by bootstrap method.
  
  
  CONCLUSIONS
  The diagnostic performance of QTFIT for CRC is promising, although its sensitivity for AP and SN is unsatisfactory. BMI, in addition to age and sex improves the accuracy of SN screening by QTFIT.
authors: St. Luke's International Hospital, Chuo-ku, Tokyo, Japan. f_omata@mac.com
authors: Fumio
authors: F
authors: Omata
authors: Ayumi
authors: A
authors: Shintani
authors: Mitsuhiro
authors: M
authors: Isozaki
authors: Katsunori
authors: K
authors: Masuda
authors: Yoshiyuki
authors: Y
authors: Fujita
authors: Tsuguya
authors: T
authors: Fukui
mesh_terms: D018256:Adenomatous Polyps / Q000175:diagnosis; D000367:Age Factors; D000368:Aged; D015992:Body Mass Index; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D055088:Early Detection of Cancer / Q000379:methods; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D007120:Immunochemistry / Q000379:methods; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D009780:Occult Blood; D012737:Sex Factors