What is a PD-L1 test and what is it used for?
A PD-L1 test uses a sample of cancerous tumor tissue to measure the levels of a protein called PD-L1 is found on the cancer cells. Normally, PD-L1 is found on healthy cells that acts as a “brake” to stop cells in your immune system, called T cells, from attacking healthy cells in your body. If cancer cells have high amounts of PD-L1, they can render the T cells ineffective.
If you’ve been diagnosed with cancer, you may require a PD-L1 test to determine whether immunotherapy can help you. Many types of cancers have immunotherapy treatments related to PD-L1, including:
- Melanoma
- Hodgkin lymphoma
- Bladder cancer
- Kidney cancer
- Breast cancer
- Head and neck cancer
- Esophageal cancer
- Stomach cancer
- Cervical cancer
What happens during a PD-L1 test?
A PD-L1 test is done on a tissue sample from a tumor. To extract this sample, a biopsy will be performed through a hollow needle inserted through your skin. If you are having surgery to remove a tumor, a sample will be taken for testing. If your test results show that you have enough PD-L1 on your tumor cells, your provider will recommend immunotherapy medicine.