Funding for this research was provided by:
Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science, and Technology of Japan (17K16434)
Received: 2 August 2017
Accepted: 29 December 2017
First Online: 18 January 2018
Ethics approval and consent to participate
: This study (R1048) was approved by the institutional review board of the Kyoto university on March 16, 2017, and was conducted in accordance with the Declaration of Helsinki and Japanese ethical guidelines for epidemiological research. Written general consent for the use of clinical data for research purposes was obtained from all patients before starting radiotherapy
: Not applicable.
: The authors declare that they have no competing interests.
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