Positive FOBT Should Trigger Colonoscopy
Even if a patient had a previous clear colonoscopy or all polyps seen on that exam were removed, a new positive fecal occult blood test (FOBT) calls for a repeat colonoscopy.
After 21,600 clear colonoscopies done at the Veterans Administration Medical Center in Phoenix, 57 patients needed a second colonoscopy after they had a positive FOBT for blood in their stool. Of those one-third (19) had a newly discovered adenomatous polyp and 3 had colon or rectal cancer. One in four of the new adenomas were advanced.
Nine of the patients with a new polyp or cancer had a history of polyps or cancer. Less than optimal bowel preparation for the initial colonoscopy was also associated with finding a new lesion.
Other reasons for blood in the stool included hemorrhoids in two-thirds of patients and diverticulosis in almost half.
Dr. Brindusa Truta, of the Phoenix VA Medical Center emphasized,
A positive fecal occult blood test after a ‘cleared’ colonoscopy should trigger a repeat colonoscopy, especially if a suboptimal bowel preparation was encountered at the initial exam.
SOURCE: Truta et al., The yield of repeat colonoscopy for a positive fecal occult blood test (FOBT) after a prior “cleared” colonoscopy, American College of Gastroenterology Annual Scientific Meeting, October 7, 2008.
This news article was originally posted on October 15th, 2008 and was accurate at the time of publication. Since then, information may have changed or links may now be outdated. Please call our Answer Line 1-877-427-2111 for the latest information, or talk to your doctor before making any medical decisions.
Posted by Kate Murphy on October 15th, 2008
Tags: colonoscopy



