The Importance of Molecular Testing in Personalized Cancer Treatment

color medicine bright background
Photo by Steve Johnson on


In the last decade or so, personalized cancer treatment has become a reality. This is due in part to advancements in genomic sequencing technology, which allows us to read DNA at a much higher level of detail than ever before. However, it’s important to realize that not all mutations are equal: Say’s Dr Joy Trueblood, some are more likely to make a tumor more aggressive while others may be less important. For example, if your tumor has an EGFR mutation (a common type of mutation found in lung cancers), then changing your treatment based on its presence may not make much difference since EGFR mutations are often found in other types of cancers as well). Therefore, we need new tools that allow us to evaluate how each mutation contributes specifically to someone’s disease process—and those tools exist!

The importance of molecular testing

Molecular testing is essential for personalized cancer treatment. For example, the expression of certain genes can be used to determine whether a patient will respond well or poorly to a particular drug. Molecular testing can also be used to identify which patients have certain genetic mutations that make them more susceptible to developing certain types of lung cancer.

In addition, the results of molecular tests may help doctors determine the best course of action in treating a patient’s disease by helping them select targeted therapies or providing information about how likely it will be that chemotherapy will work on their cancer cells.

What is molecular testing?

Molecular testing is a way of looking at the DNA of a tumor. It can help determine if a tumor is likely to respond to a particular treatment and what other types of treatments might be effective. There are many different molecular tests, including:

  • gene expression profiling (GEP) — This test looks at how much RNA from different genes is being produced in the tumor. This information helps doctors identify which genes are active within your cancer cells, which can help them predict if it will respond well or poorly to various therapies
  • immunohistochemistry (IHC) — This test examines whether there are proteins associated with certain types of cancers present on your cells’ surface

Why is it important for personalized cancer treatment?

Molecular testing is an important part of personalized cancer treatment because it helps doctors to determine the best treatment for each patient. For example, if you have been diagnosed with breast cancer and your tumor contains a mutation in the BRCA1 or BRCA2 gene, you may be at higher risk of developing ovarian cancer in the future. If this is true for you, then your doctor might recommend that they perform additional tests on your ovaries before prescribing chemotherapy or radiation therapy that might put them at risk.

Why does it matter how we test tumors for mutations?

Molecular testing is an important tool that can determine the best course of action for a patient.

It allows us to determine whether a particular treatment or drug will be effective against the tumor, as well as guide treatment decisions based on how each specific mutation affects cancer cells.


To sum up, molecular testing is an important part of personalized cancer treatment because it helps doctors determine which treatment is most likely to work for you. By testing tumors for mutations and other genetic changes, doctors can select treatments that target those specific mutations. This means fewer side effects and better outcomes overall!

Like this article?