Received: 6 June 2019
Accepted: 14 October 2019
First Online: 28 November 2019
Ethics approval and consent to participate
: All treatments were performed in the context of an individual treatment attempt as no other treatment options were left for these patients. Written informed consent was obtained from all patients. The local ethical committee waived the ethical statement due to the retrospective character of the study. All procedures were followed in accordance with ethical standards of the institutional review board and therefore been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and all subsequent revisions.
: Consent for publication is available on institutional forms and will be provided if asked.
: The authors declare that they have no competing interests