Funding for this research was provided by:
Ministry of Education, Republic of Korea (2016R1D1A1B01010316)
Received: 1 January 2020
Accepted: 19 May 2020
First Online: 4 June 2020
Ethics approval and consent to participate
: All human tissue specimens were obtained during diagnostic and therapeutic surgery. This retrospective study was performed using the tissue-paraffin block samples stored after pathologic diagnosis, and all of the samples were anonymized beforehand. This retrospective study was approved by the Institutional Review Board of Seoul National University Boramae Medical Center under the condition of anonymization (IRB No. 20150907/16–2015-124/101). The study was conducted in accordance with the principles of the Declaration of Helsinki.
: Not applicable.
: The authors declare no conflicts of interest.