What is chemotherapy? 

Chemotherapy (chemo) uses strong medicines to kill cancer cells. The medicines attack and kill cells that grow quickly, like cancer cells. Some normal cells also grow quickly. Because of this, chemo can also harm those cells. This causes side effects.

For this treatment, you’ll see a medical oncologist. This is a doctor who specializes in using medicines to treat cancer. For anal cancer, your doctor is likely to give you more than one chemo medicine. This is called combination chemotherapy.

When might chemotherapy be used for anal cancer?

Chemo given at the same time as radiation is called chemoradiation. This is often the first treatment for anal cancers that have not spread to other parts of the body. In many cases, it can cure the cancer without surgery. If chemoradiation doesn’t destroy the cancer, you may need more chemo.

Sometimes chemoradiation is given after surgery. This is done to help kill any cancer cells that may be left in your body. This can help lower the chance that the cancer will come back later.

Chemo is used if the anal cancer has spread to other parts of your body, like your lungs or liver. This can help keep the cancer from growing, slow its growth, or ease problems the tumor is causing.

How is chemotherapy given for anal cancer?

You most likely will get chemo by IV (intravenously). This means it's put right into your blood through a vein. Some chemo medicines are taken as pills. Chemo is a systemic treatment. This means the medicines travel all through your body in your bloodstream.

Most people with anal cancer get chemo in an outpatient infusion center or at their healthcare provider’s office. In rare cases, depending on your health or the medicines you get, you may need to stay in the hospital during treatment.

Chemo is given in cycles. This means you’re treated with chemo for a certain period of time. Then you have a rest period. Each treatment and rest period make up one cycle. You'll likely have many cycles of treatment. Your healthcare provider will explain what your treatment plan will be and what you can expect. The length of each treatment period and the number of cycles depend on the type of chemo you get. Monthly treatments are common. But sometimes chemo is given more often.

Some of the IV chemo medicines used for anal cancer go into your bloodstream over a short period of time. But some medicines are given as a nonstop infusion over a few days. The medicine is controlled by a small pump that's connected to your IV by a tube that carries the chemo into your blood. If you get chemo this way, you’ll need to have a long-term venous (vein) access device. It's a small tube that's put into a large vein and attached to a small drum that's just under your skin. It stays in place between cycles so that you don't have a new IV put in each time you get treatment. It might be in your upper chest or your arm. Your healthcare team will talk with you about this, the type that might be best for you, and the risks and benefits of these devices.

What are common chemotherapy combinations used to treat anal cancer?

These are the main chemo combinations used along with radiation to treat anal cancer:

• 5-fluorouracil (5-FU) and mitomycin

• Capecitabine and mitomycin

• 5-FU and cisplatin

Some of the medicine combinations used to treat anal cancer that has spread beyond the anus are:

• 5-FU and cisplatin

• Oxaliplatin, Leucovorin, and 5-FU

• Carboplatin and paclitaxel

• Cisplatin, leucovorin, and 5-FU

• Docetaxel, cisplatin, and 5-FU

What are common side effects of chemotherapy for anal cancer?

Chemo affects both normal cells and cancer cells. Side effects depend on the type and dose of the medicines you get. Ask your healthcare provider which side effects you should watch for.

Common side effects can include:

• Constipation

• Diarrhea

• Infections

• Tiredness and lack of energy (fatigue)

• Hair loss

• Mouth sores

• Nausea and vomiting 

• Loss of appetite

• Low blood cell counts

• Easy bleeding or bruising

• Numbness or tingling in fingers and toes (neuropathy)

Most side effects go away or get better between treatments. Other side effects can be permanent. There may be things you can do to help control many of these side effects. Some can even be prevented. Tell your healthcare providers about any side effects you have. They can help you manage your symptoms and keep them from getting worse.

Working with your healthcare provider

It's important to know which medicines you're taking. Write down the names of your medicines. Ask your healthcare team how they work and what side effects they might have.

Talk with your healthcare providers about what signs to look for and when to call them. For instance, chemo can make you more likely to get infections. Know what number to call with problems or questions. Is there a different number for evenings, holidays, and weekends?

It may be helpful to keep a diary of your side effects. Write down physical and emotional changes, and any changes in your thought process. A written list will make it easier for you to remember your questions when you go to your appointments. It will also make it easier for you to work with your healthcare team to make a plan to manage your side effects.