Intra-Patient Heterogeneity of Circulating Tumor Cells and Circulating Tumor DNA in Blood of Melanoma Patients.

Despite remarkable progress in melanoma therapy, the exceptional heterogeneity of the disease has prevented the development of reliable companion biomarkers for the prediction or monitoring of therapy responses. Here, we show that difficulties in detecting blood-based markers, like circulating tumor cells (CTC), might arise from the translation of the mutational heterogeneity of melanoma cells towards their surface marker expression. We provide a unique method, which enables the molecular characterization of clinically relevant CTC subsets, as well as circulating tumor DNA (ctDNA), from a single blood sample.

Towards a typology of virtual patients.

Introduction: Although on-screen "virtual patients (VPs)" have been around for decades it is only now that they are entering the mainstream, and as such they are new to most of the medical education community. There is significant variety in the form, function, and efficacy of different VPs and there is, therefore, a growing need to clarify and distinguish between them. This article seeks to clarify VP concepts and approaches using a typology of VP designs.