Suspected perianal cancer needs general physical examination, blood routine, imaging examination and histopathological examination. 1. General physical examination: when suspecting perianal cancer, one can observe whether there is any lump in the perianal area through visual examination, and touch the perianal area with anal finger-pointing to see whether there is any lump, pain, bleeding, and so on. 2. Blood routine: some cancer patients may suffer from anemia due to blood loss, which is manifested by the decrease of red blood cells and hemoglobin. 3. Imaging examination: Imaging examination such as CT can determine whether the patient has lumps and whether there are distant metastases. 4. Histopathological examination: it can clarify the nature of the mass and the pathological stage. If there is any physical discomfort and related symptoms, and perianal cancer is suspected, patients should go to the hospital for consultation in time to avoid delaying the condition.