title: Serum CD26 is related to histopathological polyp traits and behaves as a marker for colorectal cancer and advanced adenomas.
abstract: BACKGROUND
  Serum CD26 (sCD26) levels were previously found diminished in colorectal cancer (CRC) patients compared to healthy donors, suggesting its potential utility for early diagnosis. Therefore we aimed to estimate the utility of the sCD26 as a biomarker for CRC and advanced adenomas in a high-risk group of patients. The relationship of this molecule with polyp characteristics was also addressed.
  
  
  METHODS
  sCD26 levels were measured by ELISA in 299 symptomatic and asymptomatic patients who had undergone a colonoscopy. Patients were diagnosed as having no colorectal pathology, non-inflammatory or inflammatory bowel disease, polyps (hyperplastic, non-advanced and advanced adenomas) or CRC.
  
  
  RESULTS
  At a 460 ng/mL cut-off, the sCD26 has a sensitivity and specificity of 81.8% (95% CI, 64.5-93.0%) and 72.3% (95% CI, 65.0-77.2%) for CRC regarding no or benign colorectal pathology. Clinicopathological analysis of polyps showed a relationship between the sCD26 and the grade of dysplasia and the presence of advanced adenomas. Hence, a 58.0% (95% CI, 46.5-68.9%) sensitivity detecting CRC and advanced adenomas was obtained, with a specificity of 75.5% (95% CI, 68.5-81.0%).
  
  
  CONCLUSIONS
  Our preliminary results show that measurement of the sCD26 is a non-invasive and reasonably sensitive assay, which could be combined with others such as the faecal occult blood test for the early diagnosis and screening of CRC and advanced adenomas. Additional comparative studies in average-risk populations are necessary.
authors.affiliation: Universidad de Vigo, Facultad de Biología, Departamento de Bioquímica, Genética e Inmunología, As Lagoas-Marcosende s/n, 36310 Vigo, Spain. mpaez@uvigo.es
authors.forename: Loretta
authors.initials: L
authors.lastname: De Chiara
authors.forename: Ana M
authors.initials: AM
authors.lastname: Rodríguez-Piñeiro
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Rodríguez-Berrocal
authors.forename: Oscar J
authors.initials: OJ
authors.lastname: Cordero
authors.forename: David
authors.initials: D
authors.lastname: Martínez-Ares
authors.forename: María
authors.initials: M
authors.lastname: Páez de la Cadena
mesh_terms: D000236:Adenoma / Q000097:blood* / Q000453:epidemiology / Q000473:pathology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood*; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000097:blood* / Q000453:epidemiology / Q000473:pathology; D018819:Dipeptidyl Peptidase 4 / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011127:Polyps / Q000378:metabolism* / Q000473:pathology*; D011379:Prognosis; D012680:Sensitivity and Specificity; D015996:Survival Rate; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D018819:Dipeptidyl Peptidase 4