Received: 19 December 2017
Accepted: 12 February 2018
First Online: 20 February 2018
Ethics approval and consent to participate
: A written consent was received from all patients. Ethics approval was received from the Ethics Committee of the Witten–Herdecke University (Approval No.11/2016).
: A written consent was received from all patients or their legal representatives for the use of their data and specimens for research purposes.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.