Chemotherapy for Anal Cancer

Chemotherapy (chemo) uses drugs to treat cancer. Some drugs can be swallowed in pill form, while others need to be injected into a vein or muscle. The drugs enter the bloodstream to reach and destroy the cancer cells throughout the body. This makes chemo a systemic or “whole body” treatment.

To treat anal cancer, chemo can be:

  • Combined with radiation therapy (known as chemoradiation) as the first treatment for most anal cancers. This can often cure the cancer without the need for surgery. If the cancer doesn’t go away completely after chemoradiation, more chemo might be given.
  • Given along with radiation after surgery to try to kill any cancer cells that may have been left behind. This is called adjuvant therapy. It's done to lower the chance of the cancer coming back.
  • Used if anal cancer has spread to distant parts of the body, such as the liver or lungs. This can help keep the cancer under control or relieve symptoms it's causing.

In most cases, 2 or more drugs are used at the same time because one drug can boost the effect of the other.

  • The main drug combination used to treat anal cancer is 5-fluorouracil (5-FU) and mitomycin.
  • The combination of 5-FU and cisplatin is also used, especially in people who can't get mitomycin or for advanced anal cancer.

In these treatments, the 5-FU is a liquid given into a vein 24 hours a day for 4 or 5 days. It's put in a small pump that you can take home with you. The other drugs are given more quickly on certain other days in the treatment cycle. And radiation is given 5 days a week for at least 5 weeks. Talk to your treatment team about your treatment plan and how and where you will get chemo.

Side effects of chemo

Chemo drugs attack cells that are dividing quickly, which is why they work against cancer cells. But other cells in the body, like those in the bone marrow (where new blood cells are made), the lining of the mouth and intestines, and the hair follicles, also divide quickly. These cells are also likely to be affected by chemo, too, which can lead to side effects. Side effects depend on the drugs used, the amount taken, and the length of treatment. Common short-term side effects might include:

  • Nausea and vomiting
  • Loss of appetite
  • Hair loss
  • Diarrhea
  • Mouth sores

Because chemo can damage the blood-producing cells of the bone marrow, patients may have low blood cell counts. This can result in:

  • An increased chance of infection (due to a shortage of white blood cells)
  • Bleeding or bruising after minor cuts or injuries (due to a shortage of blood platelets)
  • Fatigue or shortness of breath (due to low red blood cell counts)

Along with the risks above, some chemo drugs can cause other, less common side effects. For instance, cisplatin cause nerve damage (called peripheral neuropathy). This can lead to numbness, tingling, or pain in the hands and feet.

Most side effects get better over time once treatment stops, but some can last a long time or even be permanent. If you're going to get chemo, be sure to discuss the drugs that will be used and their possible side effects.

If you do have problems, tell your doctor or nurse about any side effects as soon as you notice them. Your cancer care team can help you deal with them. For example, drugs can be used to help control nausea and vomiting. Sometimes changing the treatment dosage or how you take your medicines can reduce side effects, too.

More information about chemotherapy

For more general information about how chemotherapy is used to treat cancer, see Chemotherapy.

To learn about some of the side effects listed here and how to manage them, see Managing Cancer-related Side Effects.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: November 13, 2017 Last Revised: November 13, 2017

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