Received: 9 June 2020
Accepted: 3 August 2020
First Online: 14 August 2020
Ethics approval and consent to participate
: This study did not require official or institutional ethical approval. The material was collected post mortem and/or during routine diagnosis. According to competent authorities, this kind of research does not require ethics approval or general approval with respect to German law.
: Not applicable.
: The authors declare that they have no competing interests.