This review in the journal Cereus is very technical, but is a good summary of where we are with respect to the search for a biomarker to predict how patients are going to respond to immunotherapy medicines.

A biomarker is a substance that can be measured in the blood or body tissue to indicate a biological state, disease or condition. It can be a naturally occurring substance, gene, or characteristic (e.g. blood pressure) by which a particular biological process or disease can be identified. Biomarkers are often measured and evaluated to examine a biological response to treatment. Biomarkers are also called biological markers or molecular markers.

Recently, immunotherapies or combinations of immunotherapies and targeted therapies have become the treatments of choice for advanced kidney cancer. Unfortunately, although these medicines have been shown to improve survival in a number of cancers, many patients do not respond to these new treatments. As a result, it is critical to identify biomarkers that can predict response to immunotherapy in patients with kidney cancer. This review discusses the research investigating potential biomarkers of response to immunotherapy in kidney cancer, such as PD-1 and PD-L1. It also looks at other potential biomarkers, such as patient characteristics, particularly obesity, and inflammation.

In conclusion, the prediction of the outcomes of people with advanced kidney cancer was based on the stage, grade, subtype and overall health of the patient. Today, there are a couple of scales of risk (MSKCC and IMDC) that can be used to try to predict outcomes and improve treatment. However, based on the work done so far, there are no biomarkers that can confidently predict which patients are most likely to respond to immunotherapies in kidney cancer. There needs to be more research on the relationship between obesity and inflammation, and to further develop potential biomarkers, such as genes, to maximise the benefit of immunotherapy for patients.

Read more in Cereus here