There are several reasons for the presence of hard swellings in the anus: First, it may be an abscess under the anorectum, sometimes long-term diarrhea can lead to anal gland infection, which leads to the spread of pus to the surrounding area, sometimes forming sinus tissues under the rectal anal mucosa, rectal palpation can touch the hard sinus swelling, perform rectal ultrasound can clearly diagnose. If the patient had hemorrhoids in the past, long-term constipation, diet pepper, etc. will lead to hemorrhoid nucleus stagnation, swelling, hemorrhoid vein stasis and thus the formation of hemorrhoids, stagnation for a longer period of time will lead to the formation of thrombus, manifested as a swelling around the anus visible purple color, painful to the touch. If a lump grows inside the anus and the texture is hard, we cannot rule out whether it is anal canal cancer, we need to perform rectal examination and take biopsy for pathological histological examination to make a clear diagnosis.