A second look at colonoscopy: indications, failures, and costs
J. S. Abrams
Results of colonoscopy and colonoscopic polypectomy in 599 patients have
been reviewed. Added experience has not decreased the number of
failures--failure to examine the entire colon, polyps not retrieved for
histological examination ("lost polyps"), undetected ("missed") lesions,
and false-negative biopsy specimens. The incidence of invasive carcinoma in
polyps measuring under 1 cm is less than 1%; polypectomy should be reserved
for larger lesions or demonstrated growth of small polyps. Diagnostic
colonoscopy in selected patients (those with persistent gross or occult
rectal bleeding but normal results from sigmoidoscopic and barium enema
studies) demonstrates a causative lesion in greater than 25% and detects a
cancer in 5% to 10% of patients.
