Clinicopathologic Features and Clinical Significance of Small and Diminutive Colorectal Polyps

ABSTRACT

PURPOSE: Small (6 to 10 mm) and diminutive colon polyps (below 5 mm) are routinely removed at the time of colonoscopy for the prevention of colon cancer. Our aims in this study were to determine clinicopathologic features and frequency of significant synchronous neoplastic lesions of small colon polyps and diminutive colon polyps and to investigate development of colorectal carcinoma via surveillance colonoscopy. METHODS: We evaluated medical reports of all patients undergoing total colonoscopic examination over a 12-month period. Three hundred thirty nine small colorectal polyps, removed during colonoscopy, have been analyzed. We investigated the result of surveillance colonoscopy, also. Using this database, all adenomas were categorized into two groups Group I, < or =5 mm diameter (diminutive polyp), Group 2, 6 to 10 mm diameter (small polyp). Significant synchronous adenomas were defined as adenoma over 6 mm diameter, dysplasia or cancer. RESULTS: The most common age group was the sixth decade. The male-to-female ratio was 2.1 1. Of the small colorectal polyps, 180 (53.1%) were adenomatous, 32 (10.0%) were hyperplastic, 119 (34.9%) were chronic nonspecific inflammation, 3 (0.9 %) were lymphoid hyperplasia, and 4 (1.1%) were cancerous. The most frequent sites of these lesions were rectum and sigmoid (60.2%). Recognizable endoscopic features of polyps were redness (35.8%) and nodule (26.3%). The prevalence of advanced proximal synchronous polyps was 20.7% among patients with distal small lesions. And we detected 2 cases (25%) had new small polyps in follow up colonoscopic examination. CONCLUSIONS: All polyps should be removed when encountered during colonoscopy due to the higher prevalence of adenoma among these lesions. Effort to find new polyps via surveillance colonoscopy is needed.