title: Polarization gating spectroscopy of normal-appearing duodenal mucosa to detect pancreatic cancer.
abstract: BACKGROUND
  According to the field effect theory, by detecting microvasculature changes such as early increase in blood supply (EIBS) in the surrounding tissue, neoplastic lesions can be identified from a distance.
  
  
  OBJECTIVE
  To determine the feasibility and efficacy of a fiberoptic probe containing novel polarization gating spectroscopy technology to identify patients with pancreatic adenocarcinoma (PAC) by the field effect theory.
  
  
  METHODS
  Prospective cohort (pilot) study.
  
  
  METHODS
  Outpatient tertiary care center.
  
  
  METHODS
  Adult (≥ 18 years) patients undergoing EGD-EUS were screened. Patients with PAC were included in the "cancer" group and patients without PAC were included in the "control" group. We excluded patients with other known malignancies and gastroduodenal premalignant lesions.
  
  
  METHODS
  Spectroscopic measurements of EIBS variables, such as deoxyhemoglobin concentration (DHb) and mean blood vessel radius (BVR), were obtained from 5 periampullary locations. The Mann-Whitney rank sum test was used for the statistical analysis (P ≤ .05).
  
  
  RESULTS
  Fourteen patients (mean age 72 years, 79% male) in the cancer group and 15 patients (mean age 63 years, 60% male) in the control group were included in the final analysis. At the ampullary site, both DHb (P = .001) and BVR (P = .03) were higher in PAC patients than in the control subjects. The DHb alone (92% sensitivity, 86% specificity) or in combination with BVR (92% sensitivity, 79% specificity) can differentiate PAC from control subjects with high accuracy.
  
  
  CONCLUSIONS
  Small sample size, unmatched control subjects.
  
  
  CONCLUSIONS
  Spectroscopic measurements of EIBS by fiberoptic probes are feasible. Preliminary evidence suggests that in vivo measurement of normal-appearing duodenal tissue can differentiate PAC patients from a distance with high accuracy.
authors.affiliation: Department of Gastroenterology and Hepatology, Mayo Clinic, Jacksonville, Florida, USA.
authors.forename: Mihir
authors.initials: M
authors.lastname: Patel
authors.affiliation: Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Gomes
authors.affiliation: Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, USA.
authors.forename: Sarah
authors.initials: S
authors.lastname: Ruderman
authors.affiliation: Department of Gastroenterology and Hepatology, Mayo Clinic, Jacksonville, Florida, USA.
authors.forename: Darla
authors.initials: D
authors.lastname: Hardee
authors.affiliation: Department of Gastroenterology and Hepatology, Mayo Clinic, Jacksonville, Florida, USA.
authors.forename: Sergio
authors.initials: S
authors.lastname: Crespo
authors.affiliation: Department of Gastroenterology and Hepatology, Mayo Clinic, Jacksonville, Florida, USA.
authors.forename: Massimo
authors.initials: M
authors.lastname: Raimondo
authors.affiliation: Department of Gastroenterology and Hepatology, Mayo Clinic, Jacksonville, Florida, USA.
authors.forename: Timothy
authors.initials: T
authors.lastname: Woodward
authors.affiliation: Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, USA.
authors.forename: Vadim
authors.initials: V
authors.lastname: Backman
authors.affiliation: Department of Gastroenterology, Boston University Medical Center, Boston, Massachusetts, USA.
authors.forename: Hemant
authors.initials: H
authors.lastname: Roy
authors.affiliation: Department of Gastroenterology and Hepatology, Mayo Clinic, Jacksonville, Florida, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Wallace
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis*; D000368:Aged; D000369:Aged, 80 and over; D014670:Ampulla of Vater / Q000098:blood supply* / Q000378:metabolism; D016022:Case-Control Studies; D015331:Cohort Studies; D004386:Duodenum / Q000098:blood supply* / Q000378:metabolism; D016145:Endoscopy, Digestive System / Q000379:methods; D019160:Endosonography; D005240:Feasibility Studies; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007413:Intestinal Mucosa / Q000098:blood supply* / Q000378:metabolism; D008297:Male; D055806:Microvessels / Q000473:pathology*; D008875:Middle Aged; D009929:Organ Size; D010190:Pancreatic Neoplasms / Q000175:diagnosis*; D010865:Pilot Projects; D011446:Prospective Studies; D013057:Spectrum Analysis / Q000379:methods
chemical_list: D006454:Hemoglobins; C100003:deoxyhemoglobin