The benign and malignant nature of broad-based intestinal polyps can be determined by size, shape, extent, and pathologic biopsy. 1. Size: The appearance of benign polyps is usually small, smooth surface, regular shape and the surrounding intestinal mucosa is about the same color. The appearance of malignant polyps is generally larger, more than 1cm, usually accompanied by congestion, the surface is also irregular, and some are cauliflower-like changes. 2. Scope: benign polyp lesions are generally limited in scope, usually in the submucosal layer or in the intestinal mucosal layer. On the other hand, the scope of malignant polyps is relatively large, which may invade the intestinal muscle layer, plasma membrane layer, and may even lead to narrowing of the intestinal lumen, resulting in intestinal obstruction. 3. Pathological biopsy: Pathology is the gold standard for determining the nature of polyps, and the diagnosis is made by obtaining pathological tissue.