Bruno Paiva, PhD from the University of Navarra, Pamplona, Spain outlines the three key reasons why myeloma plasma cells circulating in peripheral blood will have a critical influence on the treatment of multiple myeloma (MM) patients. The first is that they are an important biomarker to predict clinical outcome. The second is the ability to measure a patient’s quality of life, and the third is the ability for practitioners to learn about the efficacy of treatment. Recorded at the European Hematology Association (EHA) 2016 Annual Congress in Copenhagen, Denmark.