Date Updated: 05/05/2022


Your doctor says the surgery to take out your tumor was a success, but then refers you to another doctor to consider more treatment — called adjuvant therapy.

What is adjuvant therapy?

Adjuvant therapy is often used after primary treatments, such as surgery, to lessen the chance of your cancer coming back. Even if your surgery was successful at removing all visible cancer, microscopic bits of cancer sometimes remain and are undetectable with current methods.

Adjuvant therapy given before the main treatment is called neoadjuvant therapy. This type of adjuvant therapy can also decrease the chance of the cancer coming back, and it's often used to make the primary treatment — such as an operation or radiation treatment — easier or more effective.

Adjuvant or neoadjuvant therapy can cause significant side effects, and these treatments don't benefit everyone.

Which treatments are used as adjuvant therapies?

Types of cancer treatment that are used as adjuvant therapy include:

  • Chemotherapy. Chemotherapy uses drugs to kill cancer cells throughout the body.
  • Hormone therapy. For cancers sensitive to hormones, certain treatments can stop hormone production in your body or block the effect of hormones.
  • Radiation therapy. Radiation therapy uses high-powered energy beams, such as X-rays or protons, to kill cancer cells. It can be given internally or externally.
  • Immunotherapy. Immunotherapy works with your body's immune system to fight off any remaining cancer cells by stimulating your body's own defenses or supplementing them.
  • Targeted therapy. Targeted therapy is designed to alter specific abnormalities present within cancer cells. For example, a targeted therapy is available to block the action of a protein called human epidermal growth factor receptor 2 (HER2) in women with breast cancer.

How effective is adjuvant therapy?

Because none of these treatments is completely harmless, it's important to determine the risks of adjuvant therapy versus the benefits. The following factors can help you and your doctor determine whether adjuvant therapy is appropriate for you and, if so, which type:

  • Type of cancer. Treating certain types of cancer, such as breast and colon cancer, with adjuvant therapy can be very beneficial. For some other types of cancer, there might not be a benefit.
  • Stage of cancer. A cancer's stage refers to the extent of the cancer. If the cancer is at a very early stage — before it has had time to spread — then the chance of cancer recurring after surgery may be very small. Adjuvant therapy may offer little benefit in this case. But if a cancer is at a later stage or it has spread to nearby lymph nodes, adjuvant therapy may be more beneficial.
  • Number of lymph nodes involved. The more lymph nodes involved, the greater the chance that cancer cells will be left behind after local therapy, such as surgery.
  • Hormone receptivity. Hormone therapy won't be effective if your tumor is not hormonally sensitive.
  • Other cancer-specific changes. Certain cancers may have specific changes within their cells that indicate the likelihood that your cancer will return, making adjuvant therapy more likely to be beneficial. If tests show your cancer is unlikely to recur, adjuvant therapy may offer little benefit.

Receiving adjuvant therapy doesn't guarantee your cancer won't recur. It can, however, help reduce the risk that your cancer will come back.

Is adjuvant therapy for you?

As you're deciding whether adjuvant therapy is right for you, you might want to discuss the following issues with your doctor:

  • What procedures are you considering? Find out exactly what will be expected of you during adjuvant therapy. Do you have to see your doctor for injections or will you take pills at home?
  • What are the side effects? What side effects are you willing to live with? What might be too much to tolerate? Do you plan to work or stay active during treatment? Could side effects interfere with your plans? How long will these side effects last? Are any of these side effects permanent?
  • How long will you need to take this therapy? Adjuvant treatments may last from just a few weeks to as long as 10 years. Understand what the recommendations are and why.
  • What are the chances you'll stay cancer-free? Understand how likely it is that your cancer will return if you decide against further therapy and how much improvement you might experience if you do undergo additional therapy. Your doctor can estimate how well your treatment will work based on comparisons with data from studies of other people with your same type of cancer, at the same stage and given the same treatment.
  • How is your overall health? People who are otherwise healthy may experience fewer side effects during adjuvant therapy and are more likely to benefit from the therapy. People with severe health problems may be more likely to experience side effects during adjuvant therapy and may be less likely to benefit from the therapy. If you have significant other health problems, such as heart disease or severe lung disease, then the adjuvant treatments may not help you achieve your health goals.
  • What is your preference? Some people want to do everything possible to reduce the chance that their cancer will return, no matter the side effects. Others choose not to tolerate extra side effects if there is likely to be little benefit. Ask your doctor what they recommend and why. These decisions can be very difficult, and your doctor can help you decide whether or not the benefits of adjuvant therapy outweigh the risks for you.
  • What is the cost of the therapy? Most adjuvant therapies recommended by your doctor will be covered by health insurance. However, some medications and procedures can carry substantial out-of-pocket expenses or copays. Make sure you understand how adjuvant treatment may impact your finances and if the benefits are worth the expense to you.

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