Anal cancer occurs when cancer cells form within the tissues of the anus. The anal canal or anus is a short tube at the end of large intestine and below the rectum through which stool leaves the body. Anal cancer is a rare condition that may produce symptoms such as bleeding from the anus or rectum or a lump that forms in the area. If anal cancer is diagnosed, depending on the stage of the disease, treatment may include radiation, chemotherapy, or surgery.
Stages of Anal Cancer
If anal cancer is diagnosed, additional diagnostic tests may be used to determine the stage of the cancer. Staging is based on where the cancer is located, if or where it has spread, and whether it is affecting other parts of the body. The stages of anal cancer range from stage 0 to stage 4.
In stage 0, abnormal cells are only in the first layer of the lining of the anus and may become cancerous. Stage I is characterized by a tumor that is less than 2 centimeters in size and has not spread to the lymph nodes or other parts of the body. Stage II tumors are larger than 2 centimeters but have not spread beyond the anal canal. Stage III tumors may be any size and the cancer has spread either to lymph nodes near the rectum or to other organs, such as the bladder, urethra or vagina. Stage IV anal cancer has spread to the lymph nodes and to distant parts of the body outside of the pelvis.
Treatment of Anal Cancer
Treatment for anal cancer depends on the stage of the cancer and the patient’s preferences and overall health. This disorder is often treated with a combination of chemotherapy and radiation. When they are combined, these methods enhance the effectiveness of treatment. Surgery may be recommended to treat early-stage small tumors or if a patient cannot have chemotherapy or radiation therapy.
Chemotherapy treatment involves using medication to destroy cancer cells. Chemotherapy medications are injected into a vein or taken orally as pills. The chemicals travel throughout the body, killing rapidly growing cells, such as cancer cells. Chemotherapy can cause troubling side effects such as nausea, vomiting, fatigue, hair loss and increased risk of infection.
Radiation therapy uses high-powered beams such as X-rays, to destroy cancer cells. A radiation machine is used to direct radiation beams to specific areas of the body to target cancer cells. Radiation therapy usually consists of a specific number of treatments given over a set period of time.
Surgery may be performed to remove a small tumor in the anus. During the surgical procedure, a surgeon removes the tumor and a small amount of healthy tissue that surrounds it. Surgery may also be recommended if the cancer remains after initial treatment or if it returns after treatment has been completed.
If the cancer is advanced, a more extensive surgical procedure called abdominoperineal (AP) resection may be performed. During an AP resection, the surgeon removes the anal canal, rectum and a portion of the colon. This procedure, however, results in the patient needing a colostomy bag, to collect waste or feces as it leaves the body.