Frequency of colonic adenomatous polyps in a tertiary hospital in Mumbai

Incidence of colorectal carcinoma is increasing all over world. There is limited data on colorectal polyps from India. We evaluated the histomorphological features of colorectal polyps and determined risk stratification in adenomatous polyps.

In 4970 consecutive colonoscopies, colorectal polyps were detected in 515 cases (10.3 %). Polyps were classified using standard histological criteria. Each polyp was evaluated for presence of dysplasia. Adenomatous polyps were classified as low-risk adenomas (1-2 tubular adenomas <10 mm) and high-risk adenomas characterized by villous histology, high-grade dysplasia, size ≥10 mm, or ≥3 adenomas.

Of 515 colorectal polyps, 270 (52.4 %) were adenomatous, followed by 78 (15.1 %) inflammatory, 78 (15.1 %) hyperplastic, 32 (6.2 %) hamartomatous polyps, 25 (4.8 %) benign epithelial polyps, 5 (0.9 %) cap polyps, 5 (0.9 %) lipomatous polyps, 3 (0.5 %) angiomatous polyps, 4 (0.7 %) lymphoid, and 15 (2.9 %) cases with adenocarcinoma masquerading as polyps. Mean (SD) age with colorectal polyps was 54.8 (33.0) years while for adenomatous polyps, 59.5 (14.8) years with male to female ratio of 2:1. Majority of adenomatous polyps 124 (45.9 %) were tubular adenomas present in rectosigmoid. High-grade dysplasia was found in 38 (14 %) adenomas. One hundred and fifty-five (57.4 %) were high risk of which majority were villous adenomas and nine (7.2 %) tubular adenomas.

The most common colorectal polyps found during routine colonoscopy were 270 adenomatous (52.4 %) cases. Of these, 155 (57.4 %) adenomatous polyps were high-risk category. Population prevalence data of colonic polyps in general population beyond the age of 50 years needs to be obtained.