Text and Data Mining valid from 2018-10-19
Received: 15 June 2018
Accepted: 10 October 2018
First Online: 19 October 2018
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board of National Cancer Center (reference number, 2014–233). Approval for the review of hospital records was obtained from the Institutional Review Board of National Cancer Center and the patients’ informed consent was waived given the retrospective nature of the study.
: The authors declare that they have no competing interests.
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