Anal Cancer Treatment Options. Anal cancer is treated using three methods, used either together or individually: surgery, radiation therapy, and chemotherapy. Treatment depends on the cancer stage, the extent of spread, and the patient’s age and overall health status. [Related post: Anal Cancer Prevention Tips.]
Two types of surgery may be performed. A local resection is surgery where the tumor is cut from the anus, along with some healthy tissue around it. Local resection is done if the cancer is small and has not spread. Tumors that develop in the lower part of the anus can often be removed with local resection. Persons who undergo this procedure, can save their sphincter muscles and are able to control their bowel movements. But because resection can cause anal stenosis or the narrowing of the anal canal and anus due to scar tissue, another surgery is sometimes needed to widen the anus and restore its proper function.
In stages where cancer has spread, a surgeon may have to perform an abdominoperineal resection to remove affected tissue, the rectum, part of the sigmoid colon and sections of or entire nearby organs through an incision made in the abdomen. Lymph nodes that contain cancer can also be removed during this operation. If cancer has affected your sphincter muscles, your doctor will have to do surgery with colostomy. In this procedure, he sews the end of your intestine to an opening, called a stoma, made in the surface of your abdomen so body waste can be collected in a disposable bag outside your body.
In the past, abdominoperineal resection with permanent colostomy was required for all but small anal cancers. But because this can be very debilitating, today, this is no longer the treatment of choice. In 70 percent of cases, radiation therapy alone may lead to a 5-year survival rate, although high doses may cause death of body tissue (necrosis) or the formation of excess fibrous tissues (fibrosis).
Radiation therapy uses high-energy x-rays or other types of radiation to kill cancer cells. There are two types of radiation therapy. External radiation therapy uses a machine outside your body to bombard the cancer with radiation. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires or catheters—or radioisotopic implants. These are placed directly inside your anus, near the cancerous tissues, to shrink these.
The way the radiation therapy is given depends on the type and stage of the cancer being treated. To keep the seeds in place for the appropriate length of time, you may have to go on many trips to your doctor’s office. Also, some of the side effects from radiation therapy include loss of control of the sphincter muscle (incontinence), temporary browning of the skin, and fatigue. Radiation may also be combined with chemotherapy.
Chemotherapy uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping the cells from dividing. It may be delivered via pill or needle.
When chemotherapy is swallowed or injected into a vein or muscle, the drugs enter the bloodstream to reach the cancer cells throughout the body. This is called systemic chemotherapy. In contrast, regional therapy is when chemotherapy is placed directly into the cerebrospinal fluid, an organ, or a body cavity such as the abdomen to make the drugs affect cancer cells mainly in those areas only.
The way the chemotherapy is given depends on the type and stage of the cancer being treated. The main drugs used to treat anal cancer are 5-fluorouracil (5-FU) and mitomycin or 5-FU and cisplatin. All of these drugs shrink tumors by arresting cell growth, which in turn is done by inhibiting the normal production and use of deoxyribonucleic acid (DNA)—needed for cell growth and division.