What are Cancer Vaccines?

Approved by the Cancer.Net Editorial Board, 12/2015

Listen to the Cancer.Net Podcast: Understanding Cancer Vaccines, adapted from this content.

Vaccines, also called vaccinations, are medicines that help the body fight disease. They help train the immune system to recognize and destroy harmful substances. There are two types of cancer vaccines:

  • Prevention vaccines

  • Treatment vaccines

Cancer prevention vaccines

Doctors give cancer prevention vaccines to healthy people to keep certain cancers from developing. Like vaccines for the chicken pox or the flu, they protect the body from viruses that can cause disease. A person has to get the vaccine before the virus infects him or her. Otherwise, the vaccine won’t work.

There are three cancer prevention vaccines approved by the U.S. Food and Drug Administration (FDA):

  • Gardasil. The FDA approved Gardasil for people ages 9 to 26 to prevent:

    • Cervical, vaginal, and vulvar cancers in girls and women

    • Anal cancer in women and men

    • Genital warts in men and boys

    The vaccine protects against the human papillomavirus (HPV). If the virus is long-lasting, it can cause the health conditions above. HPV can also cause other cancers the FDA hasn’t approved the vaccine for, such as oral cancer.

  • Cervarix. This vaccine also protects against HPV infection. The FDA approved it for the prevention of cervical cancer in girls and women ages 10 to 25.

  • Hepatitis B vaccine. The vaccine prevents hepatitis B virus (HBV) infection. Long-lasting infection with HBV can cause liver cancer.

Talk with your doctor about whether you should be vaccinated against HPV and HBV.

Cancer treatment vaccines

Cancer treatment vaccines, also called therapeutic vaccines, are a type of immunotherapy. The vaccines work to boost the body's natural defenses to fight a cancer. Doctors give treatment vaccines to people already diagnosed with cancer. The vaccines may:

  • Prevent the cancer from coming back

  • Destroy any cancer cells still in the body after other treatment

  • Stop a tumor from growing or spreading

How a cancer treatment vaccine works

Antigens are substances on the surface of cells that aren’t normally part of the body. The immune system attacks the antigens, usually getting rid of them. This leaves the immune system with a “memory” that helps it respond to those antigens in the future.

Cancer treatment vaccines boost the immune system's ability to recognize and destroy antigens. Often, cancer cells have certain molecules called cancer-specific antigens on their surface that healthy cells don’t have. When these molecules are given to a person, the molecules act as antigens. Then, they stimulate the immune system to recognize and destroy cancer cells that have these molecules on their surface. Most cancer vaccines also contain adjuvants, which are substances that may help strengthen the immune response.

Most cancer treatment vaccines are only available through clinical trials, which are research studies involving volunteers. However, in 2010, the FDA approved sipuleucel-T (Provenge) for men with metastatic prostate cancer, which means the cancer has spread from the prostate to other parts of the body. Sipuleucel-T is customized for each patient through a series of steps.

  • First, white blood cells are removed from the patient’s blood. White blood cells help the body fight infections and diseases.

  • Then the researcher modifies the white blood cells in a laboratory to recognize and target prostate cancer cells.

  • Next the modified cells are put back into the patient through a vein. This is similar to a blood transfusion. The modified cells teach the immune system to find and destroy prostate cancer cells.

Limitations of cancer treatment vaccines

Developing cancer treatment vaccines that work is hard because:

  • Cancer cells suppress the immune system. That’s how the cancer is able to develop and grow in the first place. Researchers are using adjuvants in vaccines to try to fix this problem.

  • Cancer cells develop from a person’s own healthy cells. As a result, the cancer cells may not “look” harmful to the immune system. The immune system may ignore the cells instead of finding and destroying them.

  • Larger or more advanced tumors are hard to get rid of using only a vaccine. This is one reason why doctors often give patients cancer vaccines along with other treatments.

  • People who are sick or older can have weak immune systems. As a result, their bodies may not be able to produce a strong immune response after vaccination. That limits how well a vaccine works. Also, some cancer treatments may damage a person’s immune system, limiting its ability to respond to a vaccine.

Because of these reasons, some researchers think cancer treatment vaccines may work better for smaller tumors or early-stage cancers.

Vaccines and clinical trials

Clinical trials are important for learning more about cancer vaccines. Researchers are testing vaccines for several cancers, including:

  • Bladder cancer. Researchers hope to better treat bladder cancer with vaccines. One study is testing the effectiveness of a vaccine made from a virus researchers modified to contain HER2 cells. These cells live on the surface of some bladder cancer tumors. The virus may help teach the immune system to find and destroy these tumor cells. Another study compares a standard bladder cancer therapy against standard therapy with a vaccine.

  • Brain tumors. There are many studies testing treatment vaccines aimed at certain molecules on the surface of brain tumor cells. Some focus on new brain cancer. Others focus on cancer that has come back, or recurred. Several of the studies include children and teens.

  • Breast cancer. Several studies are testing treatment vaccines, given alone or with other therapies, in patients with breast cancer. Other researchers are working to get prevention vaccines into clinical trials.

  • Cervical cancer. The FDA already approved two cervical cancer prevention vaccines for girls and women. Now work continues on treatment vaccines that helps treat the disease in its various stages.

  • Colorectal cancer. Researchers are creating treatment vaccines that encourage the body to attack cells with antigens thought to cause colorectal cancer. Those antigens include carcinoembryonic antigen (CEA), MUC1, guanylyl cyclase C, and NY-ESO-1.

  • Kidney cancer. Researchers are testing the use of several cancer vaccines to treat kidney cancer. They’re also testing vaccines to prevent later-stage kidney cancer from recurring. One vaccine, which a patient gets after surgery, is made from the patient’s tumor. Researchers make other vaccines from proteins found on the surface of kidney cancer cells or blood vessel cells in the tumor.

  • Leukemia. Studies are looking at treatment vaccines for various types of leukemia, such as acute myeloid leukemia and chronic lymphocytic leukemia. Some are meant to help other treatments, such as stem cell transplants, work better. Other vaccines made from a person's cancer cells and other cells may help the immune system destroy cancer cells.

  • Lung cancer. Lung cancer treatment vaccines in clinical trial target antigens. Those include MAGE-3, which is found in 42% of lung cancers and NY-ESO-1, found in 30% of lung cancers. Other target antigens include p53, survivin, and MUC1.

  • Melanoma. Researchers are testing several vaccines, given alone or with other therapies. Destroyed melanoma cells and antigens in the vaccines encourage the immune system to destroy other melanoma cells in the body.

  • Myeloma. There are several clinical trials studying vaccines in patients with multiple myeloma who are near remission. Researchers are also testing vaccines in patients with smoldering myeloma or who must have an autologous stem cell transplant.

  • Pancreatic cancer. Researchers are working on several treatment vaccines designed to boost the immune system’s response to pancreatic cancer cells. Patients receive some of the vaccine alone. Some receive a vaccine with another therapy.

  • Prostate cancer. As mentioned above, sipuleucel-T is a vaccine doctors can use to treat men with metastatic prostate cancer. Now researchers want to know if the vaccine can help men with less advanced prostate cancer.

Learn more about finding a clinical trial.

Questions to ask your doctor

If you want to learn more about joining a cancer treatment vaccine clinical trial, talk with your doctor. You may want to ask:

  • Are researchers testing a vaccine for my type and stage of cancer?

  • Where is the clinical trial located?

  • What is the vaccine and how does it work?

  • How is this vaccine made?

  • How will I receive the vaccine and how often?

  • How long will I need the vaccine?

  • What are the possible side effects?

  • Is there another treatment option for this cancer?

  • Is there anything else I need to know?

More Information

Prevention and Healthy Living

How Cancer is Treated

Additional Resource

National Cancer Institute: Cancer Vaccines