Rectal 2 cm long tip polyp erosion is not always malignant. Rectal polyps, to distinguish its benign or malignant, rely on the results of pathological biopsy. Rectal 2cm size polyp with tip, generally consider the possibility of benign, can be directly endoscopic resection, and then sent to the pathology biopsy; but its mucosa appeared erosion, need to be not excluded from the possibility of malignancy, take a biopsy and then consider the polyp resection program is more appropriate. If the direct line of resection, the pathology is malignant, may lead to tumor remnants. Rectal polyps, most of the possibility of benign, but also can not exclude the possibility of malignant, so the polyp is large, mucosal erosion, or infiltration, etc., can be considered to first consider the pathology of the biopsy, to be the results of the return to the development of the next step in the treatment measures. Whether a rectal polyp is benign or malignant must be decided according to the pathological results. Seek prompt medical attention if discomfort occurs.