病理组织学上息肉主要有三种类型：HP, AP, SSP。意义是不一样的。

Generally, colorectal polyps could be classified according to the histological types into hyperplastic polyps (HPs), adenomatous polyps (APs), and sessile serrated polyps (SSPs) Among them, APs and some subtypes of HP have been considered as precancerous lesions for colorectal cancer (CRC)