You’re likely familiar with chemotherapy (often called chemo) and its effectiveness as a cancer treatment. But you may have questions about how it works, what treatment is like and possible side effects.
The information below answers the most common questions about chemotherapy. But keep in mind that the best cancer treatment plan always depends on the type and stage of cancer, and a person’s health and preferences. So after reading through the information below, make sure to talk with your oncologist about what make sense for you or your loved one.
How chemotherapy works
Chemotherapy is a treatment that uses strong drugs to kill or slow the growth of fast-growing cells, including cancer cells. Chemotherapy doesn’t just attack cancer cells – it can also attack and damage other fast-growing cells, which causes side effects.
Most of the time, chemotherapy is given intravenously through a vein in your arm, but it can also be given orally (by mouth), topically with a skin cream, or through injections.
Chemotherapy targets cells as they grow and divide
Chemotherapy drugs target cells at different phases during the cell cycle. The cell cycle is the process every new cell goes through as it matures, and it includes four stages during which cells grow, replicate DNA and divide. For most cells, this process can take months or even years, but for fast-growing cells, the process can take as little as one day.
Cancer cells are among the fastest growing in the body and quickly move through the phases of the cell cycle. Chemo drugs are usually used to target cells during the DNA replication and cell division phases. Using chemo at these phases damages the cancer cells and helps keep the cancer from spreading. And since most cells in your body spend less time in these phases, they’re less impacted by chemotherapy drugs.
Chemotherapy as a systemic (whole body) treatment
Chemotherapy is usually a systemic treatment, meaning the drugs travel through the bloodstream, allowing it to treat cancerous cells throughout your body. Systemic chemotherapy can be especially helpful if cancer cells have spread from the primary tumor to other parts of the body. These cancer cells can be very small (micro metastases) and hard to detect, so this may be the only way to treat them.
Chemotherapy as a regional or local treatment
Chemotherapy is sometimes used as a targeted treatment for cancer cells that are contained within a specific area of the body. During regional chemotherapy, high doses of chemotherapy are delivered into or near the cancerous cells – for example, an organ or body cavity with the tumor, or an artery that supplies blood to a tumor.
Because this type of chemotherapy doesn’t travel throughout the body, it’s less likely to damage other fast-growing cells. However, it’s not effective at treating cancer cells that have spread.
When chemotherapy treatment is used for cancer
Chemotherapy is a common treatment for many different types of cancer. It’s often used to cure or slow the growth of cancer, make it less likely that cancer comes back and to control cancer symptoms.
Chemotherapy can be used alone or with other treatments
Chemo can be used alone, but it’s usually used with other types of cancer treatments, which is called a combination treatment plan. Ways that chemo is used with other treatments include:
- Before other treatments – Chemo can be used to make a tumor smaller before surgery or radiation therapy. This is called neoadjuvant chemotherapy.
- After other treatments – Chemo may be used to kill cancer cells that remain after surgery or radiation therapy. This is called adjuvant chemotherapy.
- To help with cancer symptoms – When chemo is used to help reduce symptoms of cancer, it’s called palliative chemotherapy.
Chemotherapy can be effective at all stages of cancer
Chemotherapy can be used to treat all stages of cancer. In the earlier stages, chemotherapy may be used by itself or with other treatments to treat cancer. In later stages, chemotherapy is used to make other treatments more effective or to reduce the signs and symptoms of cancer.
Chemotherapy is a good option for many types of cancers
Most types of cancers can be treated with chemotherapy, including:
- Blood cancers – Chemotherapy is often the main treatment for blood cancers like leukemia and lymphoma.
- Brain and spinal cancers – Treatment for brain and spinal tumors depends on the type, stage and location of the cancer, but chemo may be recommended if the cancer has spread from the primary location.
- Breast cancer – Surgery is usually the main treatment, but chemo can be used as a treatment for all stages of breast cancer.
- Colorectal cancer – If colorectal cancer is caught early, surgery is often the only treatment. However, if the cancer has spread, chemotherapy may be used to destroy the cancer cells that remain.
- Gastrointestinal (GI) cancer – Chemo is used for cancers of the stomach, liver and other GI organs. It can help to shrink tumors and keep them from coming back.
- Gynecologic cancers – Chemotherapy is often used to treat ovarian and uterine cancer. Depending on the type of cancer, it may be used alone or with other treatments, such as surgery or radiation therapy.
- Lung cancer – Lung cancer is usually treated with a combination of treatments. Chemotherapy is one option. Others include immunotherapy, radiation therapy, targeted therapy and surgery.
- Pancreatic cancer – Treatment of pancreatic cancer depends on the stage of the cancer and its location but may include surgery, radiation therapy, chemotherapy or a combination of therapies.
- Prostate cancer – Surgery is usually the most effective treatment for prostate cancer, but chemo may be recommended if the cancer has spread.
- Skin cancer – Surgery is the most common treatment for skin cancer, but chemotherapy is sometimes recommended, especially if the cancer has spread.
Types of chemotherapy drugs and medications
There are many different chemotherapy drugs. If chemotherapy is an option, your oncologist will share information about the specific types of chemotherapy drugs that may be used.
Chemo drugs can be delivered in different ways, including infusions, pills, liquids, creams and injections. Depending on the type of medication and your treatment plan, chemotherapy may be given during a hospital stay, at a clinic or at home.
Chemotherapy infusions
The most common way to get chemotherapy is through a needle in an arm while at a clinic or hospital. After the chemotherapy drugs are administered, the needle is removed. Chemotherapy infusions can also be given using a device placed in a vein in your chest. Intravenous chemo can take a few minutes or a few hours.
Chemotherapy injections
Some chemotherapy drugs are injected quickly using a syringe into your arm, thigh or hip, or right under the skin in the fatty part of the arm, leg or belly. Chemotherapy injections are given in a clinic or a hospital.
Chemotherapy pills or liquids
Some chemotherapy drugs come in pills, capsules or liquids that you swallow. The advantage of oral chemo is that you can take it at home.
For oral chemo to work correctly, you’ll need to carefully follow the instructions from the oncologist, which usually requires taking precise amounts of medications several times a day. Oral chemo may also require special handling. For example, you may need to wear gloves when handling the pills or return used packages to the pharmacy for disposal.
Oral chemotherapy may cost more than chemo infusions or injections since it tends to be covered as a pharmacy benefit instead of a medical treatment. If you have questions about coverage, contact member services using the information on the back of your insurance card.
Chemotherapy creams
Chemotherapy creams are topical medicines that you rub into your skin on a certain area of your body. They’re used to treat cancer cells and other fast-growing cells in the top layers of the skin. Chemotherapy creams may be an option for treating and preventing skin cancer, or managing skin-related side effects caused by other cancers. Chemotherapy creams or eye drops are sometimes used to treat certain types of eye cancers.
How often you need chemotherapy
Chemotherapy is usually given in cycles – this means there will be a period of treatment followed by a period with no treatment. An example of a 4-week cycle may be receiving chemo every day for a week, then three weeks with no chemo. The time without treatment gives the body a chance to build healthy new cells. The length of a cycle varies, but most are between 2 and 6 weeks.
The number of cycles a person needs depends on the type of chemotherapy, the type of cancer, the stage of cancer and a person’s response to chemotherapy.
Chemotherapy side effects
Chemotherapy uses special drugs to kill or stop the growth of fast-growing cells throughout the body. But since the drugs can’t tell the difference between cancer cells and healthy cells, they can damage other fast-growing cells – including those in hair follicles, bone marrow and the gastrointestinal lining. When these healthy cells are damaged, it can cause side effects.
Possible side effects vary based on the type of chemotherapy drug but include fatigue, vomiting, mouth sores, nausea, hair loss, diarrhea, loss of appetite, fever, constipation, pain and bleeding. Some people also experience thinking and memory problems (sometimes called “chemo brain” or “chemo fog”). As you discuss treatment options with your oncologist, they’ll share more information about possible side effects.
Most chemotherapy side effects go away when treatment is done, but there can be side effects that don’t show up right away or last longer. These include damage to lung tissue, nerve damage, fertility problems, kidney problems and heart problems.
Managing chemotherapy side effects
If you have chemotherapy, your care team will watch for side effects and put together a plan to help you cope with cancer treatment and stay as comfortable as possible. For example, your care team may recommend:
- Taking anti-nausea medication
- Staying hydrated
- Napping throughout the day
- Being as active as you can
- Using cannabis as part of cancer treatment
- Keeping your head covered so your scalp doesn't burn or make you too cold
- Eating small meals
What’s the difference between chemotherapy and radiation?
Radiation therapy is another cancer treatment. The differences between chemotherapy and radiation therapy include how they work and potential side effects.
Radiation therapy uses high doses of radiation to target cancer in specific areas of the body. This can be through injection into a tumor (internal radiation) or through a beam from outside the body (external beam radiation). Less often, radiation is used as a systemic treatment.
Radiation therapy generally has fewer side effects than chemotherapy, but it’s less effective at treating cancer that’s spread from the primary tumor. Side effects of radiation therapy include nausea, mouth sores, throat problems and fatigue.
There are different reasons why chemotherapy or radiation therapy may be the recommended treatment. And sometimes, they are used together. For example, if radiation therapy is used on a specific tumor, chemotherapy may be used afterward to kill cancer cells that remain. This can help keep cancer from coming back.
We’re here to ensure the best treatment for you
Chemotherapy is a common option for cancer treatment because it’s effective at killing cancer cells throughout the body. But it may not be the best option depending on the type of cancer and other factors.
At HealthPartners, we believe that cancer care should be personalized to a person’s unique needs and preferences. If you’ve been diagnosed with cancer, we’ll discuss the benefits and drawbacks of all treatment options and answer all your questions, so you know what to expect.
We use the latest research to provide the best treatments. And through clinical trials for cancer, we continue to uncover therapies and medications that provide people with the best outcomes. Talk to your oncologist if you’re interested in learning more about clinical trials.
At every step of treatment, you’ll have the support of a compassionate team of experts that includes oncologists, genetic counselors, surgeons, nurses, clinical trial researchers and many others. Whatever you need, we’re here for you.