By Mayo Clinic Staff

Your surgeon says the operation to remove your cancer was successful. So why do you need more cancer treatment? Your healthcare team might recommend more treatment to stop cancer from coming back. This is called adjuvant therapy.

Adjuvant therapy is cancer treatment that's given after primary treatments, such as surgery. The goal is to lower the chance of cancer coming back. Because even if all visible cancer is removed during surgery, there still may be some remaining in the body that can't be seen.

Types of cancer treatment used as adjuvant therapy include:

• Chemotherapy. Chemotherapy treats cancer with strong medicines. Many chemotherapy medicines exist. Most are given through a vein. Some come in pill form.
• Hormone therapy. Some types of cancer are fueled by the body's hormones. Examples include breast cancer and prostate cancer. Hormone therapy treatments use medicines to remove those hormones from the body or block their effects. This may help stop the cancer cells from growing.
• Radiation therapy. Radiation therapy treats cancer with powerful energy beams. The most common kind of radiation therapy is external beam radiation. During this kind of radiation therapy, you lie on a table while a machine moves around you. The machine directs radiation to precise points on your body. Another type of radiation is called brachytherapy. For this, a sealed radiation source is placed inside your body next to the area that needs treatment.
• Immunotherapy. Immunotherapy for cancer is a treatment with medicine that works with the body's immune system to kill cancer cells. The immune system fights off diseases by attacking germs and other cells that shouldn't be in the body. Cancer cells survive by hiding from the immune system. Immunotherapy helps the immune system cells find and kill the cancer cells.
• Targeted therapy. Targeted therapy for cancer is a treatment that uses medicines that attack specific chemicals in cancer cells. By blocking these chemicals, targeted treatments can cause the cancer cells to die.

Not everyone benefits from adjuvant therapy. Consider these factors with your healthcare team when deciding if adjuvant therapy is right for you:

• Type of cancer. Adjuvant therapy often works well for certain types of cancer, such as breast cancer and colon cancer. But it depends on your unique situation. Adjuvant therapy may not help treat all types of cancer.
• Stage of cancer. A cancer's stage shows how much the cancer has spread. If the cancer is at an early stage, it may not have had time to spread. The chance of cancer returning after surgery may be quite low. In that case, adjuvant therapy may not offer much benefit. Adjuvant therapy may be more helpful if a cancer is at a later stage or has spread to nearby lymph nodes.
• Number of lymph nodes involved. When cancer spreads from where it started, it often goes to the lymph nodes first. If your cancer has spread to the lymph nodes, you may be more likely to benefit from adjuvant therapy.
• Hormone receptivity. Hormone therapy won't be effective if your cancer is not fueled by specific hormones.
• Other cancer-specific changes. Certain cancers may have changes within their cells that show that cancer is likely to return. In these cancers, adjuvant therapy may be helpful. If tests show that your cancer is not likely to return, you may not need adjuvant therapy.

Adjuvant therapy doesn't ensure your cancer will not return. But it can lower the risk of the cancer coming back.

To decide if adjuvant therapy is right for you, discuss the following points with your healthcare professional:

• Type of therapy. Find out exactly what to expect during adjuvant therapy. Do you have to see your healthcare professional for injections or will you take pills at home?
• 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 treatment lasts. Adjuvant treatments may last from just a few weeks to as long as 10 years. Understand what the recommendations are and why your healthcare professional is making them.
• Chances of staying cancer-free. What are the chances the cancer will return if you decide against further therapy? How much will adjuvant therapy help you? Your healthcare professional can estimate your treatment effectiveness by looking at studies of other people with the same type and stage of cancer who had the same treatment.
• Effects of overall health. People in otherwise good health may have fewer side effects during adjuvant therapy. They also may be more likely to benefit. People with serious health problems may be more likely to have side effects during adjuvant therapy. They also may be less likely to benefit. If you have other major health problems such as heart disease or serious lung disease, you may not benefit as much from adjuvant treatments.
• Cost. In the United States, most adjuvant therapies recommended by your healthcare professional are likely to be covered by health insurance. But you may be expected to pay for some part of the treatment. Some medicines and procedures can be expensive. Prepare by asking about costs and what you can expect. If you're concerned about affording treatment, let your healthcare team know about your concerns. Ask to talk with a medical social worker who can connect you with financial resources that might help.

Carefully think about what you prefer. You may want to do everything to lessen the chance of your cancer returning despite any side effects. Or you may decide you don't want the extra side effects if the therapy isn't likely to help much. Talk with your healthcare professional about what's recommended and why. Your healthcare professional can help you decide whether the benefits of adjuvant therapy outweigh the risks for you.