Once presence of the cancer is confirmed in your anus, your doctor will perform other medical procedures to determine its stage. The staging test is not only important to have an idea of the severity of the tumor but also to determine the best treatment to use. Usually, anal cancer progresses in the following stages:
Carcinoma in situ – also called Stage 0, the carcinoma in situ indicates the genesis of the cancer cells; the tumor foundin the top layer of the anal tissue. Stage 0 anal cancer represents a minor threat, and barely causes symptoms.
Stage I – during this period, the tumor is usually less than 2 centimeters in diameter; the cancer has affected muscle tissue of the sphincter, and tend to be symptomatic.
Stage II – Stage II anal cancer is characterized by an increased size of the tumor, usually larger than 2 centimeters in diameter. The cancer has spread beyond the top layer of the anal tissue, but has not affected nearby organs.
Stage IIIA – during this phase, the cancer has increased in size, and has spread beyond the anal canal to affect nearby organs such as the bladder, urethra or vagina.
Stage IIIB – at this stage, the cancer has increased considerably in size. It has spread beyond the anal canal, and can affect the lymph nodes around the rectum, in the groin or in the abdomen. The symptoms become more serious.
Stage IV – the cancer, in this final stage, has spread from the anal area to distant parts such asliver and the lungs. A Stage IV anal cancer usuallycauses serious symptoms.