title: A prospective single centre study comparing computed tomography pneumocolon against colonoscopy in the detection of colorectal neoplasms.
abstract: OBJECTIVE
  To determine the sensitivity and specificity of computed tomography (CT) pneumocolon in the detection of colorectal neoplasms.
  
  
  METHODS
  A total of 201 consecutive patients with colorectal symptoms or requiring surveillance for colorectal neoplasms underwent both conventional colonoscopy and CT pneumocolon.
  
  
  RESULTS
  On conventional colonoscopy 13 invasive colorectal carcinomas were detected in 13 patients, and 118 polyps in 63 patients (14 polyps were > or =1 cm in diameter, 25 were 6-9 mm, and 79 were < or =5 mm). CT pneumocolon detected all 13 cancers, two false positive cancers, but only 20 polyps (seven were > or =1 cm). This resulted in a sensitivity of 100% (95% confidence interval (CI) 87-100%) and specificity of 99% (95% CI 97-100%) for detection of invasive carcinoma, and a sensitivity of 73% (95% CI 56-90%) and specificity of 94% (95% CI 91-98%) for detection of invasive carcinoma and/or > or =1 cm polyps. CT pneumocolon also identified invasive carcinoma not seen at colonoscopy because of incomplete examination in three patients, and detected metastases in six colorectal carcinoma patients and extracolonic carcinoma in a further seven patients.
  
  
  CONCLUSIONS
  CT pneumocolon had a high sensitivity and specificity for detection of invasive colorectal carcinoma but not colorectal polyps. CT pneumocolon may be suitable for initial investigation of patients with symptoms of colorectal malignancy.
authors.affiliation: Department of Gastroenterology, Chelsea and Westminster Hospital, London, UK.
authors.forename: Y M
authors.initials: YM
authors.lastname: Miao
authors.forename: Z
authors.initials: Z
authors.lastname: Amin
authors.forename: J
authors.initials: J
authors.lastname: Healy
authors.forename: P
authors.initials: P
authors.lastname: Burn
authors.forename: N
authors.initials: N
authors.lastname: Murugan
authors.forename: D
authors.initials: D
authors.lastname: Westaby
authors.forename: T G
authors.initials: TG
authors.lastname: Allen-Mersh
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003111:Colonic Polyps / Q000175:diagnosis; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000209:etiology; D010147:Pain Measurement; D017060:Patient Satisfaction; D011029:Pneumoradiography / Q000379:methods*; D011446:Prospective Studies; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*