Mayo Clinic Health Library

Adjuvant therapy: Treatment to keep cancer from returning

Updated: 05-03-2012

You've had surgery to take out your tumor, and your surgeon says all the cancer was removed. Yet, you've been referred to another doctor to consider more treatment — called adjuvant therapy. You may wonder why you need additional treatment when your cancer has already been removed.

Even if your surgery was successful in removing all visible cancer, there may be a chance that your cancer could return. Doctors feel this may be due to microscopic bits of cancer that may remain and are undetectable with current methods. Depending on your specific case, you may benefit from adjuvant therapy, since this additional treatment may reduce the risk that your cancer will return.

Adjuvant therapy is used after primary treatments, such as surgery or radiation. But the added benefit of adjuvant therapy doesn't come without a price — the side effects can be more than minor inconveniences.

Not everyone benefits from adjuvant therapy. Work with your doctor to determine if adjuvant therapy is right for you.

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. Chemotherapy treats the entire body, killing cancer cells, no matter where they may be located. Adjuvant chemotherapy isn't helpful in all situations, so talk to your doctor about whether this treatment is right for you and how much of a benefit it may provide.
  • Hormone therapy. Some cancers are sensitive to hormones. For these cancers, treatments to stop hormone production in your body or block the effect of hormones on your cancer may be helpful. Cancers that are commonly hormone sensitive include breast, uterine and prostate cancers. Your cancer will be analyzed to see if it's hormone sensitive. If it is, you might benefit from hormone therapy. Hormone therapy can be used in conjunction with surgery, radiation or chemotherapy.
  • Radiation therapy. Radiation therapy uses high-powered energy beams, such as X-rays, to kill cancer cells. Radiation therapy can be given internally or externally. Adjuvant radiation therapy focuses on the area around the original cancer site to reduce the risk that cancer will recur in that area.
  • Immunotherapy. Immunotherapy works with your body's own immune system to fight off remaining cancer cells. Immunotherapy treatment can either stimulate your body's own defenses or supplement them.
  • Targeted therapy. Targeted therapy aims to alter specific abnormalities present within cancer cells. For example, women with a type of breast cancer that makes too much of a protein called human growth factor receptor 2 (HER2) may choose a targeted therapy drug that blocks the action of that specific protein. These medications target the specific protein within those cancer cells. More targeted therapies are under development and may one day be available for use as adjuvant therapy.

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 with adjuvant therapy can be very beneficial. Examples include breast cancer and colon cancer. 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. If cancer is at a later stage — if it is a larger tumor or if the cancer has spread to nearby lymph nodes — then the chance that cancer will reappear sometime in the future is much greater. Adjuvant therapy may be more beneficial in this case.
  • 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. If tests show your cancer is unlikely to recur, adjuvant therapy may offer little benefit. If tests show your cancer has a greater chance of recurring, you're more likely to benefit from adjuvant therapy. Your doctor may request special testing of your cancer cells to determine if adjuvant therapy would be beneficial.

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. Will 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? Which ones will be too much for you to tolerate? Do you plan to work or stay active during treatment? Could side effects interfere with your plans?
  • 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.
  • 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. Discuss your preferences with your doctor.

Together you and your doctor can weigh these factors and decide whether the benefits of adjuvant therapy outweigh the risks for you.