172

K Tsoi, DG Morgan

McMaster University, Division of Gastroenterology, Hamilton, Ontario

BACKGROUND: Changes in the type of patients undergoing colonoscopy has occurred over the past decade. More colonoscopies are being done per year and many polyps are removed. Whether this polypectomy activity has led to a higher yield in pathological diagnosis of premalignancy has not been established. The yield of polyps with high grade dysplasia and/or cancer was reviewed.

METHODS: All office patient charts from the year 2002 and between 1991-93 were manually reviewed to identify patients for the study. Inclusion criteria: 1) Patient age greater than 18; 2) Patient had colonoscopy during the period identified; 3) At least one colonic biopsy/polypectomy was obtained and successfully retrieved during the procedure for pathological analysis.

RESULT: 345 biopsy samples were identified in 136 patients in 2002; 341 samples in 201 patients from 1991-93. Comparison between 2002 and 1991-93 populations yielded the following: Gender: 46.6% vs 41.7% male, Age: 60.0±14.0 vs 55.8±20.6 years; Indications for colonoscopy: bleeding per rectum (20% vs 34.6%), anemia (6% vs 11%), changes in bowel habit (21% vs 26%), weight loss (2% vs 0.8%), abdominal pain (6% vs 8.7%), search for unknown primary malignancy (0% vs 1.6%) and follow-up from previous positive colonoscopy (41% vs 17%). Pathological diagnosis: invasive carcinoma (0.3% vs 7.6%), carcinoma in-situ (0% vs 0.6%), adenoma (25.6% vs 11.2%), hyperplastic (38.2% vs 3.6%), inflammatory changes (5.9% vs 16.7%), normal biopsy (28.0% vs 54.1%) and others (1.5% vs 5.2%).

CONCLUSION: More adenomatous and hyperplastic biopsy samples but significantly less carcinoma was seen in 2002 vs 1991–93. High grade dysplasia was seen in less than 2% of all biopsies. These findings likely result from increased screening colonoscopy in individuals with increased risk for polyps and less colonoscopy for abnormal symptoms. More follow-up colonscopies will be generated from the 2002 findings than from those of 1991–93. This has long term cost implications. A larger study is warranted to better assess the costs and benefits of colonoscopy.

NEXT ABSTRACT >