Funding for this research was provided by:
Singhealth Surgery Academic Clinical Program (the SingHealth Surgery ACP Surgeon-Scientist Strategic Start-up (S4G) Grant)
Received: 10 May 2019
Accepted: 23 September 2019
First Online: 23 October 2019
Ethics approval and consent to participate
: This study was conducted with the approval of the SingHealth Centralized Institutional Review Board (CIRB Ref: 2016/2819). A waiver of consent was granted given the retrospective nature of the project, and that archival tissue was used.