They also sought to understand the features of the adenomas they were finding and how they may differ between genders. They found that in patients with adenomas, there was no statistical difference between males and females in adenomas that were large, flat, contained advanced histology or were located in the right colon — all features associated with an increased risk of colorectal cancer (CRC). The researchers reviewed data from 2,400 colonoscopies and focused on average-risk patients who were undergoing CRC screenings. (Average-risk means someone who has never had polyps and does not have a family history of CRC.)

Dr. Coe suggested it might be feasible to adjust guidelines to provide benchmarks for the detection of advanced adenomas. However, investigators do not truly know what the upper limit of detection is, so while rates are improving, investigators are unsure how many adenomas can feasibly be detected overall. While benchmarks serve as an important quality target, there still may be considerable room for improvement.

She added that there is a lot of exciting technology on the horizon centered on methods of detecting advanced adenomas and CRC. “It will be interesting to see how these tests complement and improve colorectal cancer screening in the future,” she stated.

Dr. Coe expects that next steps will look at gender differences in the detection rate of serrated polyps. “These polyps, which tend to be subtle, large, flat, hyperplastic-appearing polyps in the right colon, may account for at least some of the cancers that later develop after a negative screening colonoscopy.”

No pharmaceutical funding was provided for this study.

Dr. Coe will present these data on Monday, May 21 at 3 p.m. PT in Room 4 of the San Diego Convention Center.

Patient Perception of Bowel Preparation for Colonoscopy is Associated with the Quality of Preparation (Abstract #Tu1737)

A patient’s perceived experience with bowel preparation predicts the cleanliness of the colon and the detection of polyps during colonoscopy, according to new research from California Pacific Medical Center, San Francisco. Previous studies have shown a link between the quality of bowel preparation and the detection rate for pre-cancerous adenomas. In this study, researchers sought to determine how certain patient-related factors might also affect the detection of polyps, which decreases the risk of colorectal cancer.

With this in mind, investigators led by Edward W. Holt, MD, gastroenterology fellow at California Pacific Medical Center, surveyed 430 patients immediately prior to colonoscopy to learn how much of the bowel prep they thought they had completed, how clear their bowel movements were after the prep, and their impression of the overall tolerability of bowel preparation. The actual cleanliness of the colon and the adenoma detection rate were then measured during colonoscopy.

Results showed that 94 percent of participants reported completing at least 95 percent of the preparation, 97 percent reported completely liquid bowel movements after prep, and 21 percent rated their experience with the bowel prep as “good.” Patients who gave their prep a favorable rating by any of these three criteria were found to have significantly cleaner colons during colonoscopy — at colonoscopy, 87 percent of the bowel preps were scored as excellent. Furthermore, patient-perceived tolerability of bowel preparation was independently associated with what was found during colonoscopy: patients who reported the worst experience with bowel preparation had significantly lower rates of adenoma detection.

Dr. Holt believes that results of this study raise the possibility that colonoscopy may be more effective when providers take extra time to explain the bowel preparation process and to set realistic expectations for patients. If a patient is not physically or mentally prepared for the prep, does not know how it can be made more tolerable or does not understand why the prep is such an important part of the colonoscopy, then he or she may benefit less from the procedure, in addition to walking away unhappy.

He cautioned against inferring from this research that improving the patient’s experience with bowel preparation will guarantee the detection of more polyps and a lower risk of death from colon cancer. He emphasized that this study highlights the importance of the patient’s experience and role in the process of colonoscopy for colon cancer screening. However, many factors influence the effectiveness of colonoscopy as a screening tool, including how soon it is performed post-bowel prep, how long the procedure takes and the cleanliness of the colon.

The study does not account for why the patient’s experience may be so important, but there are several possibilities. In particular, if the taste or the sheer volume of bowel prep causes a patient to drink less of it, it could prevent adequate cleansing of the colon, making it harder for the physician to detect polyps.

“If the bowel prep experience is intolerable for the patient, it could have implications beyond the time when the patient is actually trying to drink the prep — it may hinder our ability to detect polyps during the colonoscopy,” said Dr. Holt. “Putting more emphasis on a better patient experience may be another way to increase the possibility of removing pre-cancerous polyps.”