title: Faecal calprotectin and lactoferrin as markers of acute radiation proctitis: a pilot study of eight stool markers.
abstract: BACKGROUND
  Non-invasive diagnostic tools to evaluate the severity of acute, radiation-induced proctitis are not readily available. The faecal excretion of eight markers of gut inflammation was therefore examined. Five proteins and three lipid derivates were analysed in sequential stool samples taken before and during radiation therapy.
  
  
  METHODS
  Stool samples from 15 patients with prostate cancer scheduled for radiation therapy were examined. Pretreatment and in-treatment samples (2nd and 6th weeks) were measured by enzyme-linked immunosorbent assay (ELISA) (calprotectin, lactoferrin, transferrin, leukotriene B4, prostaglandin E2, thromboxane B2 and TNF alpha) or nephelometry (alpha 1-antitrypsin).
  
  
  RESULTS
  Calprotectin and lactoferrin concentrations increased significantly during radiation treatment (P = 0.0005 and P = 0.019). Transferrin was detected in only 9 out of 45 samples. There were no changes in tumour necrosis factor alpha (TNF alpha), leukotriene B4, prostaglandin E2 and thromboxane B2 during treatment. alpha 1-antitrypsin could not be detected in any sample.
  
  
  CONCLUSIONS
  This study indicates that faecal calprotectin and lactoferrin concentrations could be markers of acute, radiation-induced proctitis. Patient compliance and stability of the markers make this a promising method for clinical research. Eicosanoids could be measured in stool samples, but the concentrations did not increase with increasing radiation dose.
authors.affiliation: Department of Oncology, Haukeland University Hospital, NO-5021 Bergen, Norway. annette.larsen@helse-bergen.no
authors.forename: A
authors.initials: A
authors.lastname: Larsen
authors.forename: N
authors.initials: N
authors.lastname: Hovdenak
authors.forename: A
authors.initials: A
authors.lastname: Karlsdottir
authors.forename: T
authors.initials: T
authors.lastname: Wentzel-Larsen
authors.forename: O
authors.initials: O
authors.lastname: Dahl
authors.forename: M K
authors.initials: MK
authors.lastname: Fagerhol
mesh_terms: D000208:Acute Disease; D000368:Aged; D015415:Biomarkers / Q000032:analysis; D015232:Dinoprostone / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D005243:Feces / Q000737:chemistry*; D006801:Humans; D007781:Lactoferrin / Q000032:analysis*; D039841:Leukocyte L1 Antigen Complex / Q000032:analysis*; D007975:Leukotriene B4 / Q000032:analysis; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011349:Proctitis / Q000175:diagnosis* / Q000209:etiology; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000175:diagnosis*; D014168:Transferrin / Q000032:analysis; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis; D000515:alpha 1-Antitrypsin / Q000032:analysis
chemical_list: D015415:Biomarkers; D039841:Leukocyte L1 Antigen Complex; D014168:Transferrin; D014409:Tumor Necrosis Factor-alpha; D000515:alpha 1-Antitrypsin; D007975:Leukotriene B4; D007781:Lactoferrin; D015232:Dinoprostone