Funding for this research was provided by:
Shanghai Municipal Commission of Health and Family Planning (20164Y0155)
Pudong New Area Science and Technology Development Foundation (PKJ2016-Y41)
Received: 18 February 2019
Accepted: 22 July 2019
First Online: 6 August 2019
Ethics approval and consent to participate
: This retrospective study was approved by the Ethics Committee of Shanghai Proton and Heavy Ion Center. Written informed consent was obtained for each participant before enrolling in this study.
: Written informed consent for publication was obtained for each patient before enrolling in this study.
: The authors declare that they have no competing interests.