Received: 3 November 2020
Accepted: 17 February 2021
First Online: 7 April 2021
Ethics approval and consent to participate
: This research is retrospective and involves the collection of existing data and records. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration. The ethical committee of Hospital Ramón y Cajal of Madrid approved all procedures of the study and provided a waiver for the written informed consent.
: Not applicable.
: The authors have no conflicts of interest to declare.