Chemotherapy for Anal Cancer

Chemotherapy drugs are used to kill cancer cells. These drugs destroy cancer that is still left after surgery, slow the tumor's growth, or reduce symptoms. Chemotherapy is usually most effective for treating anal cancer when it is combined with radiation therapy. The combined treatment allows your doctor to use lower radiation doses, which can reduce the side effects of radiation. It also increases the chance that your treatment will completely destroy the tumor.

The main chemotherapy drugs used to treat anal cancer are combinations of 5-fluorouracil (5-FU) and mitomycin or 5-FU and cisplatin.

• Adrucil ^® or Efudex ^® (5-fluorouracil or 5-FU) - 5-FU belongs to the group of chemotherapy drugs known as antimetabolites. 5-FU prevents cells from making DNA and RNA, which stops cells from growing. 5-FU is given as a shot in the vein over 5 to 10 minutes or 20 to 60 minutes, or continuously over 22 to 24 hours for 1 to 4 days or longer. The treatment can be repeated every week, every other week, or every 3 weeks. The dose depends on your size and blood count.

• Mutamycin^® (mitomycin) - Mitomycin belongs to a group of chemotherapy drugs known as antibiotics, but it acts like an alkylating agent. It blocks the cell from making DNA, which results in cell death. Mitomycin is given by an injection in a vein over 20 minutes every 6 to 8 weeks. The dose and how often you get the medicine depend on your weight, your blood counts, how well your kidneys work, and the type of cancer you have.

• Platinol^® (cisplatin) - Cisplatin is a platinum compound chemotherapy drug that acts like an alkylating agent. It stops cancer cells from growing, which kills them. Cisplatin is given by an injection into the vein over at least 1 hour. Your dose depends upon the type of cancer you have, your size, blood counts, and how well your kidneys work.

If you are treated with both radiation therapy and chemotherapy (radiotherapy), you will probably get the chemotherapy during the first and fifth weeks of your radiation treatments.

If you have been infected with the human immunodeficiency virus (HIV, the virus that causes AIDS), you are more likely to have side effects during and after chemotherapy treatment. The chemotherapy can weaken your immune system, which is already vulnerable because of the HIV. These side effects could make it harder for you to go through and complete treatment. For this reason, your doctor may recommend lower doses of chemotherapy if you have HIV.

This content has been reviewed and approved by Myo Thant, MD.