1. Department of Dermatology, Skin Cancer Center Ruhr‐University Bochum Bochum Germany
2. Department of Pathology and Cytology Augusta Kliniken Bochum Hattingen Bochum Germany
3. Pathologisches Institut Recklinghausen Recklinghausen Germany
4. Department of Dermatology and Allergology Klinikum Vest GmbH Recklinghausen Germany