Received: 13 June 2017
Accepted: 18 April 2018
First Online: 27 April 2018
Ethics approval and consent to participate
: Ethics approval for this study was obtained from the Ethics Review Committee of the Faculty of Medicine, Colombo, Sri Lanka (Ref. No. EC-16-206). As only anonymised previously collected data were obtained from the National Cancer Registry for analyses, no patient consent process was involved.
: The authors declare that they have no competing interests.
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