title: Patients with colorectal cancer are characterized by increased concentration of fecal hb-hp complex, myeloperoxidase, and secretory IgA.
abstract: OBJECTIVE
  The aim of our study was to evaluate the use of fecal hemoglobin-haptoglobin (Hb-Hp) complex, myeloperoxidase (MPO), and secretory IgA as potential diagnostic markers for the screening of colorectal cancer.
  
  
  METHODS
  Our study consisted of 190 participants (150 patients and 40 healthy individuals) aged 40 to 70 years who underwent complete colonoscopy. From each participant, a stool sample was collected 1 day before colonoscopy. The patients were instructed to collect another sample after the fourteenth postoperative day. No special diet was recommended.
  
  
  RESULTS
  In the control group, all fecal markers were within normal values in most participants. Colorectal tumors were accompanied by a highly significant increase in all markers. The median value of Hb-Hp complex was 23.22±10.02 (P<0.0001) whereas the median values of MPO and sIgA were 14936.43±9580.83 (P<0.0001) and 6503.38±2794.87 (P<0.0001), respectively. The sensitivity and specificity of Hb-Hp complex, MPO, and sIgA are 95.3% and 87.5%, 96% and 87%, and 90.8% and 85%, respectively. The difference of preoperative and postoperative values of the patients was statistically significant for all markers. After surgical intervention, the value of Hb-Hp complex was normalized in 133 of the 150 patients (88.7%). The postoperative values of MPO were within normal limits in 131 patients (87.3%), whereas those of secretory IgA were within normal limits in 103 of the 150 patients (68.5%).
  
  
  CONCLUSIONS
  Fecal Hb-Hp complex, MPO, and sIgA can effectively be used as screening tools for the early diagnosis of colorectal cancer, and for the postoperative follow-up of patients.
authors.affiliation: First Propaedeutic Surgical Department, University of Athens, Hippokration Hospital, Greece. thanoschalkias@yahoo.gr
authors.forename: Athanasios
authors.initials: A
authors.lastname: Chalkias
authors.forename: George
authors.initials: G
authors.lastname: Nikotian
authors.forename: Anastasios
authors.initials: A
authors.lastname: Koutsovasilis
authors.forename: John
authors.initials: J
authors.lastname: Bramis
authors.forename: Andreas
authors.initials: A
authors.lastname: Manouras
authors.forename: Dimitra
authors.initials: D
authors.lastname: Mystrioti
authors.forename: Vaggelogiannis
authors.initials: V
authors.lastname: Katergiannakis
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D015179:Colorectal Neoplasms / Q000737:chemistry* / Q000175:diagnosis* / Q000378:metabolism; D005243:Feces / Q000737:chemistry; D005260:Female; D006242:Haptoglobins / Q000032:analysis*; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D007071:Immunoglobulin A, Secretory / Q000032:analysis*; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D009195:Peroxidase / Q000032:analysis*; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; D006242:Haptoglobins; D006454:Hemoglobins; D007071:Immunoglobulin A, Secretory; C035492:haptoglobin-hemoglobin complex; D009195:Peroxidase