The usefulness of currently available colon imaging tests, including air contrast barium enema (ACBE), computed tomographic colonography (CTC), and colonoscopy, to detect colon polyps and cancers is uncertain.
Dr Rockey and colleagues from America undertook a study in order to assess the sensitivity of these 3 imaging tests.
The researchers carried out 2 separate colon-imaging studies on patients with fecal occult blood, hematochezia, iron-deﬁciency anemia, or a family history of colon cancer.
The research team oversaw air contrast barium enema, followed 7–14 days later by computed tomographic colonoscopy and colonoscopy on the same day, for each participant.
| Lesions 10 mm or larger in size: |
Sensitivity of ACBE - 48%
The primary outcome was detection of colonic polyps and cancers.
The researchers assessed outcomes by building an aggregate view of the colon, taking into account results of all 3 tests.
In total, 614 patients completed all 3 imaging tests.
The research team analyzed results on a per-patient basis, and found that for lesions 10 mm or larger in size, the sensitivity of ACBE was 48%, CTC 59% and colonoscopy 98%.
In addition, the researchers noted that for lesions 6–9 mm in size, sensitivity was 35% for ACBE, 51% for CTC, and 99% for colonoscopy.
Dr Rockey concluded, "For lesions of 10 mm or larger in size, the speciﬁcity was greater for colonoscopy than for either ACBE or CTC and declined for ACBE and CTC when smaller lesions were considered."