Chemotherapy is one type of treatment for anal cancer that most patients will need to undergo to some extent. Here, we’ll look at what chemotherapy for anal cancer consists of, when it is used and the main side effects.

What is chemotherapy treatment for anal cancer?

Chemotherapies are a class of drugs that kill cancer cells and prevent them from multiplying.

When is chemotherapy used?

Anal cancers between stages I-III are often treated with the chemotherapy drugs mitomycin-C and 5-fluorouracil (5-FU) in addition to radiation.

For stage IV cancers, the NCCN recommends a combination of 5-FU and cisplatin, which is a platinum-based therapy. There are encouraging results from studies that have employed either a combination of paclitaxel, carboplatin, and 5-FU; a combination of carboplatin and paclitaxel; or single-agent paclitaxel. These treatment regimens are being tried in part because they have shown efficacy in other cancers, such as lung and head and neck cancer.

Several other single-agent or combination treatments have been tested in clinical trials and case studies, with varying success. We believe a better standard of care for all stages of anal cancer needs to be established and support research to better understand and treat it.

An international study took place to investigate the most effective chemotherapy regimen for recurrent or metastatic anal cancer. Results were published in 2020. This 60-center study compared the results of two treatment regimens for patients with locally recurrent or metastatic anal cancer. One arm consisted of cisplatin and 5-FU, and the other consisted of carboplatin and paclitaxel. Although overall response rates were the same between arms, reduced side effects and potentially longer survival rates suggested that carboplatin plus paclitaxel should be considered as a new standard of care.

Which chemotherapy drugs are used to treat anal cancer?

There are two chemotherapy drugs that are the basis of the standard treatment for anal cancer stages I to III: 5-fluorouracil (5-FU) and mitomycin C. In stages I to III, these chemotherapies are combined with radiation. The combination of 5-FU and the drug cisplatin may also be used, especially in cases of advanced cancer. Any stage cancer may be treated with or without radiation. There are also ongoing studies that have employed either a combination of paclitaxel, carboplatin and 5-FU, a combination of carboplatin and paclitaxel, or single-agent paclitaxel.

How is chemotherapy administered?

For anal cancers between stages I-III, chemotherapy is typically administered twice, once at the beginning of radiation and then again at 5 weeks of radiation. Before treatment, a temporary central venous catheter (“CVC”) or peripherally inserted central catheter (“PICC”) may be placed on an individual. These allow for chemo infusions from 96 to 120 hours at a time. Recently, 5-FU has become available in pill form, which may be administered every day to patients who could benefit from taking it this way.

Side effects of chemotherapy for anal cancer

Common side effects of 5-FU and mitomycin C include, but are not limited to: decreased white blood cells, decreased red blood cells and/or platelets, nausea, vomiting, mouth sores, hair loss, neuropathy and fatigue.

The side effects of cisplatin, paclitaxel and carboplatin differ from one another and from person to person. The most common side effects of cisplatin include nausea, vomiting, appetite and hair loss, and diarrhea. The most common side effects of paclitaxel include nausea, weakness, darkening of skin or nails, temporary hair loss or irritation and swelling at the injection site. The most common side effects of carboplatin include pale skin, lightheadedness, easy bruising or unusual bleeding, and flu-like symptoms.

Your doctor will most likely give you an anti-nausea drug before the chemotherapy begins. Let the medical team know if you continue to experience nausea despite this medication.

Individuals taking these drugs should be sure to discuss any severe and/or unusual side effects with their care team immediately.

Effects on blood cell count (anemia)

Mitomycin-C, cisplatin and 5-FU frequently lower your blood cell count. Your oncologist will monitor this carefully and adjust the dosage if need be. You may experience increased fatigue as a result of lowered red blood cells, and lowered white blood cells can put you at greater risk of infection. Additionally, if you have any heart or lung problems, please tell your oncologist; adverse effects on these organs are rare, but the doctor needs to know what to look out for.

5-FU can also lower platelet counts in the weeks following treatment. This can increase your risk of bleeding and you may experience increased nosebleeds, bleeding gums, black tarry stools etc. You should notify your doctor if you experience any of these.

I stayed “quarantined” in my house for a week, then was hospitalized for a week for a fever when my immune system was wiped out. I lost my hair, my lunch, my appetite, and 30 pounds. I have been inspired by other cancer patients and survivors, and their positive outlooks. I decided that no matter what, I would do my best to stay positive. Now a year and a half later, I’m asked often if I am cured. My answer: so far, so good.

Connie (Stage II)

Effects on the mouth

Oral hygiene is important before and during treatment. Chemotherapy can cause side effects in the mouth, with mouth sores being the most common. See your dentist for a thorough cleaning before treatment as well as any dental work that you will need in the near future. Speak with your healthcare team about seeking dental cleaning before starting treatment.

If you have problems with mouth sores you may be prescribed an antibiotic mouthwash. Speak with your provider about whether the a baking soda rinse (see recipe) would work with your treatment plan. Be sure to gently brush your teeth with as soft a brush as possible after meals, and if recommended by your health care provider, use the NIH recommended mouthwash. Please note that this should not be used as a substitute for medical advice or information. Check with your doctor before taking any action.

The chemo made me nauseated and created a side effect in my mouth (blistering of gums), which was downright awful.

Tony (Stage IIIB)

Tiredness and fatigue

It is quite common to feel tired when undergoing chemotherapy – though this is not a given. Again, everyone’s body will react differently and in different ways to treatment. Tiredness can be caused by the drugs themselves, lack of sleep, not being able to eat as usual, or a drop in red and/or white blood cell count. Lowered red blood cell counts mean your blood cannot carry oxygen efficiently to your tissues, leading to fatigue. This is also known as anemia. Lowered white blood cell counts mean that your body’s ability to fight infection is lessened and your immune system has to work harder to prevent illness.

It may be difficult to deal with feeling tired all the time, especially if you are usually a high-energy person. Be sure to ask for help from family and friends as needed, and try to limit activities that make you tired. Try to adjust working hours with your employer, or even work from home if that is possible. Fighting your tiredness may only make things worse so listen to your body and rest when you need it.

Perhaps somewhat counter-intuitively, exercise can help fight fatigue and increase energy. Studies have shown that mild, enjoyable exercise can help improve physical energy and appetite, increase a sense of wellbeing and better one’s quality of life. It is important not to overexert yourself, but to find ways to be active that you enjoy. Your care team can help you select activities and plan a schedule for both rest and activity that are safe and work best for you.

Tiredness and Fatigue After Treatment

The tiredness and fatigue experienced as part of side effects during chemotherapy may continue for six months to a year after treatment ends. Tiredness is primarily caused by lowered red and white blood cell counts as a result of chemotherapy, and these counts take time to rise again. The more intensive the chemo regimen, the longer it will take to feel like you have regained your former energy levels.

Changes in nutrition can also affect fatigue. A poor appetite may impact the amount of beneficial nutrients you’re able to take in, and your body may process nutrients less efficiently due to changes in your metabolism. You may also need more energy than usual for cell repair both during and after chemotherapy. Speak with a registered dietitian to ensure you are still getting the needed nutrients even if you are experiencing poor appetite or side effects such as diarrhea or vomiting.

Exercise can help with managing tiredness. Any sort of enjoyable physical activity (walking, yoga, tai chi – whatever you like!) for 3-5 hours/week has been linked to improved appetite, mood, outlook and coping abilities in thrivers during and after undergoing treatment. Keeping a regular activity/rest cycle to help your body get on a schedule may help as well. Speak with your doctor and care team about how to ensure you get enough rest, as well as for resources that can help you manage your daily activities. It is important to still do physical activity, make sure to speak with your provider and physical therapist about what is safe.

Hair loss

It is rare for someone receiving the standard chemoradiation treatment for anal cancer to completely lose all of their hair, though again everyone reacts to chemotherapy differently. Individuals with recurrent or advanced cancer who receive the standard chemotherapy treatment for this often have complete hair loss as the protocol is different. Thinning hair or hair loss may happen to you, usually starting two to three weeks after starting chemotherapy. Eyelashes and eyebrows may also be affected.

Hair loss occurs because chemotherapy prevents cell growth. While this may have the intended effect of preventing the growth of the tumor, it also affects healthy cells as well, and during treatment can limit the growth of hair in addition to blood cells.

Cutting hair short or shaving it off is a way of dealing with the shock of thinning or hair loss. Thrivers sometimes use scarves, baseball caps and wigs if that’s what they want to do. For thinning hair, try to treat it as gently as possible, using baby products and soft combs and avoiding harsh dye jobs, perms or styling implements. The good news is that once chemotherapy ends, hair changes begin to reverse themselves.

Skin and nail changes

Chemotherapy drugs can cause changes in the skin and nails. Skin may become dry, discolored, and more sensitive to sun and chemicals. Nails may also turn dry and brittle, and you may see white lines forming on them.

It is suggested to avoid sun exposure, and be sure to use sunblock while you are still receiving chemotherapy. Swimming in chlorinated water may aggravate your skin as well. Using un-perfumed moisturizers and oils on your skin and nails can help manage these symptoms. Ask your doctor if there is anything else in particular you can or should, or shouldn’t, be doing. Avoid using creams on any areas being treated by radiation without checking with your doctor first. Finally, the marks on your nails should grow out over time. If you wear nail polish, avoid quick-drying types as they can dry your nails out even more.

Bleeding

5-FU can reduce platelet counts in the weeks after therapy. This may result in more nosebleeds, gum bleeding, black tarry stools, etc., as well as an increased risk of bleeding. Unusual bleeding is a common side effect of carboplatin.

You should notify your doctor if you experience any of these.

Diarrhea

Diarrhea is a common side effect of cisplatin alongside nausea, vomiting and loss of appetite. It is very important drink lots of fluids if you are experiencing chemotherapy-related diarrhea.

Speak to your doctor if you cannot take in the recommended fluids. If dehydration is severe, help can be provided through intravenous hydration.

Hearing loss

Cisplatin can damage your hearing and affect the inner ear, which in turn may cause balance problems. Occasionally deafness will occur. Let your doctor know about hearing loss, if you experience ringing in your ears, or a loss of balance. Your doctor may monitor your hearing before and throughout treatment if you are taking this drug.

Changes to your sex life

Chemotherapy’s effects on sex life are experienced differently by everyone. Some people may feel overly tired, sick or sore, contributing to a lowered sex drive. Others remain energized throughout treatment. Changes to sex drive in both men and women tend to reverse themselves after the course of chemotherapy is over. Regardless, it is advised to speak with your doctor before continuing or resuming your sex life. Discuss with them the impact of treatment on sexual activity. In addition, it is important to use contraception if pregnancy is a risk, as becoming pregnant while either partner is undergoing chemotherapy may put fetal development at risk.

If you are a woman using hormonal or implanted contraception and you are about to start or have started chemotherapy, be sure to tell your doctor and ask if it is safe to continue using medical contraception. It can interact with chemotherapy and can slightly increase the chance of blood clots.

There is no evidence that chemotherapy drugs can affect your partner through sex. To be safe, however, it is advised to use some form of barrier protection when having sex during chemotherapy and up to a week after finishing. This applies regardless of which partner is undergoing treatment. In addition, if you are a woman who has not yet undergone menopause and you have a male partner, you could still be producing eggs even if your periods stop during treatment (see the Fertility Section below for more information). You may therefore be able to get pregnant so it is advisable to continue using contraception throughout.

The combination of chemotherapy and radiation has different side effects on a thriver’s sex life than undergoing chemotherapy alone. Please see our Radiation Therapy for Anal Cancer page for more information.

Fertility

Chemotherapy drugs can cause infertility, either temporarily or permanently. In men, chemotherapy may reduce the number of sperm you produce, and/or affect your sperm’s ability to fertilize an egg. In women, it can stop your ovaries from producing eggs. In women who have not yet undergone menopause, periods may become irregular and can stop completely, leading to an early menopause. Side effects of this include hot flashes, dry skin and vaginal dryness, loss of energy and sex drive, and mood swings.

If you still plan to have children after undergoing treatment, talk to your doctors to explore your options. They may be able to suggest treatment that is less likely to affect your fertility. Sperm-banking and freezing embryos or unfertilized eggs may also be possibilities. Many doctors advise people to wait at least two years after chemotherapy has ended to get pregnant in order to assess recurrence. As being pregnant with cancer comes with its own unique set of challenges, inclusive of the ability to undergo treatment, doctors tend to advise waiting for this risk period to pass.

Fertility is such a personal and sensitive issue—it can be helpful to seek support to cope with potential side effects of chemotherapy on your ability to have children. Thrivers and their partners have found that going to specialized counseling can help them manage and express their feelings. Your doctor or care team may be able to provide resources. In addition, the Anal Cancer Foundation’s Peer to Peer Support Program can help match you with thrivers who have also experienced fertility issues. Talking to others who have gone through similar experiences may help bring you some comfort with regard to chemotherapy-linked infertility and help answer other concerns you may have.

More information on what you might expect during treatment can be found here:

Chemotherapy-induced peripheral neuropathy

Chemotherapy can cause peripheral neuropathy. This means damage to nerves that are further away from the central nervous system. Symptoms include, but are not limited to, tingling in the hands and feet, pain of varying severity, trouble picking things up with your fingers, and balance issues.Read about an extended list of symptoms and possible causes other than chemotherapy. Please tell your oncology team immediately if you experience any of these. They may need to adjust your treatment plan accordingly.

'Chemo-Brain'

This refers to the mental fogginess that thrivers sometimes notice during and after cancer treatment. This can result in side effects such as memory loss, trouble concentrating, trouble multitasking, trouble remembering common words and loss of other cognitive functions. How long this lasts, and its severity, can vary widely from person to person. Some people may only experience brief periods of mental cloudiness, while others may suffer more long-term cognitive problems. Make sure to speak with your healthcare provider if you are experiencing these symptoms. The American Cancer Society and Cancer Research UK provide more information on chemo brain, and a list of tips and tricks to help manage its sometimes-frustrating effects.

Infection

During a chemotherapy treatment cycle there will be times when your white blood cell count is particularly low. Lowered white blood cell counts mean that your body’s ability to fight infection is lessened and your immune system has to work harder to prevent illness.

Stress, poor nutrition, and not enough sleep can also weaken the immune system, making infection more likely at these times.

Preparation for this means making your living space clean and tidy and getting used to washing your hands often.

Preparing for chemotherapy treatment

Diet

Healthy foods on a table

Eat a healthy and enjoyable diet while you await treatment. Building a good nutritional base before treatment can help thrivers stick to a healthy routine once chemotherapy is underway. It may be helpful to prep healthy meals and snacks that you can freeze for those days you are unable to cook. Scheduling friends and family to come eat with you and/or bring you meals may also help make eating easier once you are in treatment. Stocking up on non-perishable, healthy and enjoyable items will also help for times that you are unable to get to the store. As chemotherapy can reduce your white blood cells which fight infection, you should speak with your provider to make sure it is safe to eat fresh produce, as it may need to be cooked.

Oral Hygiene

See your dentist for a thorough cleaning as well as any dental work that you will need in the near future. Chemotherapy has a tendency to cause mouth sores (or ‘ulcers’) which may make it hard to brush or floss during much of your treatment. You’ll want to help prevent dental problems by starting with a clean and cared-for mouth. Always tell your healthcare providers when you plan to get see a dentist.

Memorial Sloan Kettering Cancer Center recommends incorporating a rinse of baking soda and warm water into your nightly routine to help ward off sores once chemotherapy starts. They suggest combining one quart (4 cups) of water mixed with 1 teaspoon of salt and 1 teaspoon of baking soda. . Take small sips of this mixture and swish it around your mouth for a few seconds before spitting and rinsing with clean water. Look for toothpastes that do not contain sodium lauryl sulfate to avoid further mouth irritation. Please note that this should not be used as a substitute for medical advice or information. Check with your doctor before taking any action.

Cleanliness

Plan ahead to minimize exposure to germs. Chemotherapy can cause a low white blood cell count, limiting your ability to fight off infections. Preparation for this means making your living space clean and tidy and getting used to washing your hands often.

Transportation

Arrange for transport to and from chemotherapy appointments, at least for the first few sessions, as you may not know how your body is going to react to treatment. It may help alleviate some of the anxiety of treatment if you know there is a reliable ride waiting to take you home. Speak to the hospital’s social worker as they may be able to help arrange transport. Review our Financial Resources page to see organizations that assist with treatment transport services.

Emotional Support

Rest and a healthy diet can help manage physical side effects of chemotherapy, but it is important to take care of your emotional needs, too. Begin looking for support groups where you can express your anxiety, fears and any other emotions you may experience during chemotherapy. Anal Cancer Foundation’s Peer to Peer Support Program links thrivers with one another and is an outlet for mentorship and experience sharing.

Undoubtedly your family and friends will love and support you through this time, but many patients experience undue strain if they try to keep on a ‘happy face’ to avoid putting those close to them through pain. Having the support of others who know what you are going through can help with management of emotional stress and may be crucial to maintaining your emotional health.

I think that as survivors we are so brainwashed into staying “positive”, that we brush our feelings under the rug.

Lori D. (Stage I/II)

Some helpful questions to consider asking your care provider before starting chemotherapy are:

  • What chemotherapy medications will I be taking?
  • What are the side effects of these medications?
  • Will I be prescribed additional medications to help manage side effects?
  • Are there any medications I should avoid, such as over-the-counter medications and herbal and dietary supplements?
  • Can I continue taking my existing medications?
  • Should I eat before chemotherapy?
  • Who should I call if I have a question or a problem? What are the daytime and nighttime numbers?

During treatment

Doctor diagnosing patient

There are two chemotherapy drugs that are the basis of the standard treatment for anal cancer stages I to III: 5-fluorouracil (5-FU) and mitomycin C. In stages I to III, these chemotherapies are combined with radiation. The combination of 5-FU and the drug cisplatin may also be used, especially in cases of advanced cancer. Any stage cancer may be treated with or without radiation. There are also ongoing studies that have employed either a combination of paclitaxel, carboplatin and 5-FU, a combination of carboplatin and paclitaxel, or single-agent paclitaxel.

Common side effects of 5-FU and mitomycin C include, but are not limited to: decreased white blood cells, decreased red blood cells and/or platelets, nausea, vomiting, mouth sores, hair loss, neuropathy and fatigue.

The side effects of cisplatin, paclitaxel and carboplatin differ from one another and from person to person. The most common side effects of cisplatin include nausea, vomiting, appetite and hair loss, and diarrhea. The most common side effects of paclitaxel include nausea, weakness, darkening of skin or nails, temporary hair loss or irritation and swelling at the injection site. The most common side effects of carboplatin include pale skin, lightheadedness, easy bruising or unusual bleeding, and flu-like symptoms.

Your doctor will most likely give you an anti-nausea drug before the chemotherapy begins. Let the medical team know if you continue to experience nausea despite this medication.

Individuals taking these drugs should be sure to discuss any severe and/or unusual side effects with their care team immediately.

Diet during treatment

During chemotherapy, it is important to eat enough protein and calories to keep up your strength and help rebuild tissue. Some people experience no problems with eating, though many people do find that they are unable to have many of the same foods as before. You may also find that food is not appetizing during treatment, as the chemotherapy drugs affect your taste buds. This can cause some people to lose weight. If you feel you are losing weight, make sure to check by weighing yourself. If you ARE losing weight, please notify your healthcare provider.

The key is to eat what you can tolerate, when you can tolerate it. Inform your doctor if you have been unable to eat for two days. A bland diet has been helpful to thrivers when managing eating issues during chemo. Maintaining a wholly balanced diet of three square meals a day during treatment may not be feasible for some people. Breaking meals up into smaller, frequent snacks can help, and always be sure to listen to your body’s cues. Talk to your healthcare provider about what you can do to get the nutrition you need in a way that works with you, your body and your treatment protocol.

It is imperative that you get enough liquids, especially on days when you are unable to eat. If you have trouble eating or swallowing fluids, you may need help to stay hydrated. It is very important to do so, including to help flush the chemo drugs out of your system. This is especially important if you are on cisplatin, as this drug can cause damage to the kidneys, and water is essential to help protect them. Fluid intake is also important if you are experiencing chemotherapy-related diarrhea. Tell your doctor if you cannot take in the recommended fluids. Help can be provided by intravenous hydration if your dehydration is severe.

Helpful food tips

  • Some people find lemon-flavored or tart foods more palatable. Try adding lemon drops to your water or drinking lemonade. Lemon chicken might be a more edible main dish and a tart lemon custard might taste better at this time as a sweet. If you have a sore mouth or throat, however, some of these suggestions might sting a little, so be sure to listen to your body and medical team.
  • Add extra flavor to your food to make it more appealing. Herbs, sauces and marinades can help with this.
  • If you have a metallic taste in your mouth, try using plastic utensils.

The National Cancer Institute has put together a helpful eating guide for individuals undergoing treatment for cancer. Please note that this should not be used as a substitute for medical advice or information and check with your doctor before taking any action.

Connect with a Peer

Anal cancer can often be an isolating experience, and even if you have a supportive circle of family and friends, unless they have been through anal cancer treatment themselves there is often a limit on their understanding. Our peer-to-peer support program aims to address this gap, matching anal cancer thrivers seeking support from trained peer mentors who have been through treatment. Mentors provide 1:1 connection from the framework of those who have shared within this incredibly difficult experience.

We also provide caregiver matching as well.

The cancer thrivers who participate in the program, whether offering or receiving mentorship, build deep friendships and express relief at having found a knowledgeable and empathetic community. After recovery, many support-seekers come back to serve as mentors in the program themselves.

Learn more and sign up on our Peer-to-Peer Support page.