Get To Know Your Tumor and Biomarkers

Every person has a unique pattern of biomarkers, many of which have been monitored throughout our lives. Measurements made during a routine doctor’s visit, such as blood pressure or body weight, are simple examples. Other biomarkers can be based on laboratory tests of blood, urine, or tissues. Broadly speaking, biomarkers are characteristics of the body that can be measured or detected to better understand your diagnosis, potentially predict how it will progress, and/or potentially help determine the best treatment.

Cancer biomarkers are more precise than the measurements taken during a routine visit with your doctor. Cancer cells were originally healthy cells, so your doctor needs ways to spot the disease in a sea of normal cells and tissues. Biomarkers may include genes, proteins, and other substances that provide information about your cancer. Some biomarkers can even help us understand how to treat specific forms of cancer by indicating what treatments that particular cancer may be sensitive or resistant to.

What Are Biomarkers Used For?

Cancer biomarkers can be used in a variety of ways:

Risk Assessment

Some biomarkers can help determine if you are at higher risk of developing a disease than the general population. For example, high cholesterol could indicate a higher risk of developing heart disease, or elevated blood sugar could correspond to a higher risk of developing diabetes. When assessing cancer risk, doctors often look at your family history and for specific genetic mutations.

For example, a BRCA (BReast CAncer gene) mutation screening evaluates your family history and looks for specific genetic mutations, which are abnormal changes found in your DNA that prevent genes from doing their jobs properly. A BRCA mutation could increase the risk of developing certain types of cancer, including breast cancer, in your lifetime. It is important to remember that an increased risk does not mean that you are guaranteed to develop the disease—it simply means that you should talk with your doctor about ways to reduce the risk and set up a plan for regular screenings.

Early Detection

Screening biomarkers can be used to find cancers at early stages when they are easier to treat. For example, PSA screening for prostate cancer looks for the presence of a specific protein in the patient’s blood, and some colorectal cancer screening tests detect cancer DNA in a stool sample. Blood tests to detect multiple cancers at once are being developed and may become a game-changing tool in the future.

While screening can catch some cancers early, we have not yet discovered reliable biomarkers for all cancer types. That’s why Stand Up To Cancer is supporting research into early detection and the development of early treatment approaches in our Cancer Interception Program.

Diagnosis and Monitoring

Doctors diagnose cancers by evaluating several different factors. These factors include determining where the tumors occur in the body, how widespread they are, what they look like on medical imaging, and sometimes what symptoms they may be causing. More and more, doctors are able to look for the presence of specific proteins, gene mutations, or other substances to help understand how the disease may progress.

These diagnostic biomarkers can be used to help you and your medical team better understand your cancer and how it changes in response to therapy. Some cancers, such as breast and lung, have a variety of diagnostic biomarkers, while others, like pancreatic cancer, have few or none. SU2C supports research to find and develop new diagnostic biomarkers, especially in difficult-to-treat cancers.

Biomarkers and Cancer Treatments

There are more than 200 types of cancer. Each one is treated differently according to various factors such as the type of cancer, stage of the disease, and specific genetic mutations associated with the cancer. While surgery and radiation are often used, they are usually combined with other treatments such as chemotherapy, targeted therapies, or immunotherapy.

Cancer biomarkers can help your medical team determine the most effective treatments for you. Sometimes, the presence of a biomarker will indicate that a therapy targeted at a particular weakness in the tumor may be effective. For example, Herceptin (trastuzumab) is often prescribed for breast cancers carrying HER2 gene mutations.

In other cases, combinations of biomarkers will help your doctor suggest a treatment plan. There are many different biomarker tests; some are specific to one cancer type while others can be used across a variety of cancers. Some biomarker tests look for gene changes in cancer cells, or they detect key proteins. Some tests look at a single biomarker while others look for a pattern among multiple biomarkers. These tests are often done using tumor samples removed during a biopsy or surgery, but tests using samples of blood or other bodily fluids are becoming more common.

Knowing your cancer biomarkers will help you and your doctor select treatments that specifically target your cancer and help you avoid treatments that may not be effective. In addition, you may want to consider participating in a clinical trial that is focused on developing new treatments targeting one or more of your cancer biomarkers.

How Can I Learn More About My Biomarkers?

Cancer care continues to improve as we learn more about the biology of cancer and the ways in which our bodies support tumor growth. This is good news for patients, as new, more effective treatments are being developed with less severe side effects.

It is important to talk to your doctor about biomarker tests that might be right for you. Before having this conversation, you may want to think of some questions. Stand Up To Cancer has developed some points to think about when talking to your doctor, and the National Cancer Institute has more information about biomarker tests and a list of common cancer biomarkers used today. 

Cancer Support Community provides a Talking About Biomarker Testing guide with a biomarker testing tool included, which can be found on their website.

Why It Matters

Philanthropy is inherently an investment in the making of a better world. Stand Up To Cancer was built upon the bold belief in a future where no one dies from cancer. Thanks to the tireless effort of the brilliant researchers whose work we have supported, and to your generous support of SU2C, our vision is closer than ever to becoming reality.

— Julian Adams, Ph.D., President and CEO, Stand Up To Cancer