Received: 21 August 2019
Accepted: 5 November 2019
First Online: 5 December 2019
Ethics approval and consent to participate
: Our study protocol was approved by the Medical Ethics Committee of Drum Tower Hospital Affiliated with Nanjing University Medical College. All patients admitted at our center had consented to the anonymous use of their medical data for scientific research, publication and/or quality assessment, and informed consents were previously signed at the beginning of their treatments. Because the study was designed to retrospectively analyze the data of patients who had finished their treatments, further consent was not necessary.
: Not applicable.
: The authors declare that they have no competing interests.