PHOENIX – When the entire colon cannot be examined during a colonoscopy, physicians should persevere in obtaining a full colonic evaluation because a sizable share of these patients will have an advanced polyp or cancer, a new study shows.
In the study, which used a prospective institutional database, about 1 in every 8 patients having an incomplete initial colonoscopy were subsequently found to have a clinically significant lesion after undergoing some other type of completion exam, lead investigator Dr. Timothy J. Ridolfi reported at the annual meeting of the American Society of Colon and Rectal Surgeons.
Patients with a personal history of polyps or cancer accounted for two-thirds of all patients who were found to have lesions on completion studies.
"Complete colonic evaluation in patients with an incomplete colonoscopy is important, and repeat colonoscopy is the most efficient way of achieving that," he commented. "Those with a personal history of polyps or cancer have the highest likelihood of a positive finding on repeat colonoscopy."
Session attendee Dr. Joshua Bleier, of the Hospital of the University of Pennsylvania, Philadelphia, asked, "Since you have this prospective database, was any chart review done to follow up on the patients who didn’t have completion evaluations?"
The investigators have not yet assessed outcomes among patients who were offered a completion study but skipped it, according to Dr. Ridolfi, who is a colorectal surgery fellow at the Cleveland Clinic. He noted that some patients may have had such studies done at outside institutions.
Dr. H. David Vargas
Commenting on the research in an interview, comoderator Dr. H. David Vargas, of the Ochsner Medical Center in New Orleans, said that although the study’s findings are not surprising, they are a good reminder to physicians of the need to follow through in cases where a colonoscopy cannot be completed.
Examining the entire colon "is really incumbent upon us. The onus is on us to complete it," he said. The study "confirms why we need to be thorough, if you will."
The investigators analyzed data from a prospective database that captured information on 25,645 colonoscopies performed by colorectal surgeons at the Cleveland Clinic between 1982 and 2009.
A total of 242 patients were identified as having an incomplete initial colonoscopy. The group had a mean age of 59 years, and 69% were women.
The leading reasons for an incomplete procedure were presence of stool, pain, and tortuosity, with the reason varying according to the anatomic extent of the procedure. Fully 71% of procedures were terminated at the splenic flexure or more distally, he reported.
Overall, 90% of the patients were offered some type of completion study, and 82% of this group complied and underwent the study.
The completion study was most commonly a barium enema (41%) or repeat colonoscopy (40%), and less commonly CT colonography (9%), colonoscopy under general anesthesia (5%), or indicated resection with intraoperative or perioperative colonoscopy (5%).
Some 12% of the patients undergoing a barium enema or CT colonography were found to have new abnormalities, according to Dr. Ridolfi.
In addition, 24% of the patients undergoing repeat colonoscopy were found to have polyps. Of the 32 polyps identified (21 located beyond the extent of the initial incomplete colonoscopy), 9 were advanced adenomas.
And 38% of the patients undergoing indicated resection were found to have some additional lesions on their intraoperative or perioperative colonoscopy.
Patients whose indication for the initial colonoscopy was a personal history of polyps or cancer were more likely than those with other indications – a family history, symptoms, or screening – to have lesions on their completion study. In fact, these patients made up 67% of all patients with positive findings.
Ultimately, 12% of the patients undergoing completion studies were determined to have clinically significant lesions that led to polypectomy or partial colectomy.
Dr. Ridolfi disclosed no relevant conflicts of interest.