Received: 18 February 2021
Accepted: 23 May 2021
First Online: 5 June 2021
: <b>T</b>he study was performed in accordance with the ethical standards as laid down in the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. According to the ethics review board of the university of Regensburg an ethical review for this analysis is not required due to quality assurance data that is used in this analysis. Patients’ permissions for processing their data for quality assurance was obtained from the treatment contract.
: Not Applicable.
: CB, CK, NTS and SW are employees of Deutsche Krebsgesellschaft e. V. (German Cancer Society, DKG) and SD and JF are employees of OnkoZert, the two bodies responsible for the certification of organ cancer centers. OO is board member of the German Cancer Society. FS reports grants from AstraZeneca GmbH, grants from Abnoba GmbH, grants from Helixor GmbH and grants from Iscador AG outside the submitted work.