Gerold Schuler, MD of University Hospital Erlangen, Erlangen, Germany discussed the field of biomarkers in melanoma at the 2016 World Congress on Cancers of the Skin (WCCS) and the Congress of the European Association of Dermato-Oncology (EADO) in Vienna, Austria. At present there is no biomarker that can discriminate between patients who will respond to checkpoint blockade therapy or who will have side effects to checkpoint blockade treatment, which is currently a big problem in the field. Prof. Shuler believes biomarkers are an excellent tool and are useful when examining the tumour microenvironment and the blood. A new area of interest is the gut microbiome, which can influence an individual’s immune response and response to checkpoint blockade. Prof. Schuler is currently performing a Phase III uveal melanoma vaccine trial, looking into potential biomarkers. Patient stool specimens have been collected as part of the study to investigate the role of the gut microbiome in treatment response.