Text and Data Mining valid from 2019-01-10
Received: 6 August 2018
Accepted: 2 January 2019
First Online: 10 January 2019
Ethics approval and consent to participate
: We got approval from the National Cancer Institute to use data of patient from SEER database. Participant consent was not necessary as this study involved the use of a previously-published de-identified database according to SEER database.
: Not applicable
: The authors declare that they have no competing interests.
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