Dr. Johnson on the Limitations of Biomarkers in Melanoma

Douglas B. Johnson, MD, MSCI, assistant professor of medicine, Vanderbilt University Medical Center, clinical director, Melanoma Research Program, Vanderbilt-Ingram Cancer Center, discusses the limitations of biomarkers in melanoma.

Identifying novel biomarkers in melanoma has been a challeng​ing area of research, says Johnson.

Initially, PD-L1 expression was evaluated as a way to determine whether patients should receive single-agent PD-1 ​inhibitors or the combination of ​PD-1 plus ​CTLA-4 inhibitors, Johnson explains. However, longer follow-up data have failed to show PD-L1 as a robust biomarker of response.

In addition, since PD-L1 is now used less in melanoma compared with other cancers, ​tumor mutational burden has become a biomarker of interest. Although it appears to correlate with response, the utility of this potential biomarker remains unclear, Johnson concludes.