Funding for this research was provided by:
Deutsche Krebshilfe (70111850, 109076)
Ministry for Innovation, Science and Research of the State of North Rhine-Westphalia (323-8.0302.16.02-132142)
Received: 21 September 2017
Accepted: 10 January 2018
First Online: 24 January 2018
Ethical approval and consent to participate
: Written informed consent was obtained from all patients and control individuals, and ethical approval was granted by the Ethics Committee of the University of Cologne (07-048).
: Not applicable.
: The authors declare that they have no competing interests.
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