About the Authors

Amaya Viros

Affiliation Department of Dermatology, University of California San Francisco, San Francisco, California, United States of America

Jane Fridlyand

Affiliations University of California San Francisco (UCSF) Comprehensive Cancer Center, University of California San Francisco, San Francisco, California, United States of America , Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California, United States of America

Juergen Bauer

Affiliation Department of Dermatology, University of California San Francisco, San Francisco, California, United States of America

Konstantin Lasithiotakis

Affiliation Department of Dermatology, University of Tübingen, Tübingen, Germany

Claus Garbe

Affiliation Department of Dermatology, University of Tübingen, Tübingen, Germany

Daniel Pinkel

Affiliations University of California San Francisco (UCSF) Comprehensive Cancer Center, University of California San Francisco, San Francisco, California, United States of America , Department of Laboratory Medicine, University of California San Francisco, San Francisco, California, United States of America

Boris C Bastian

To whom correspondence should be addressed. E-mail: bastian@cc.ucsf.edu

Affiliations Department of Dermatology, University of California San Francisco, San Francisco, California, United States of America , University of California San Francisco (UCSF) Comprehensive Cancer Center, University of California San Francisco, San Francisco, California, United States of America , Department of Pathology, University of California San Francisco, San Francisco, California, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

AV performed the quantitation of the microscopic features and was involved in the project design, statistical analysis, and writing of the manuscript. JF is responsible for the statistical analysis. JB performed sequencing of BRAF and NRAS in a subset of the samples and was involved in scoring of microscopic features of a subset of the samples. KL and CG performed the statistical analysis of the Southern German Tumor Registry cohort. DP participated in the design of the study and the writing of the manuscript. BCB oversaw the entire project and was involved in the overall project design, data analysis, and writing of the manuscript.