Text and Data Mining valid from 2019-05-17
Received: 11 December 2018
Accepted: 13 May 2019
First Online: 17 May 2019
Ethics approval and consent to participate
: The databases are not publicly available. Formal ethical approval and patient consent for this study was not required. The Fribourg cancer Registry has a general authorization to collect nominative data and to analyse the anonymized data.
: Not applicable.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.