Acknowledgements
We acknowledge the Qatar National Library for funding the open access publication of this article. We also acknowledge the Medical Research Center at Hamad Medical Corporation for their support.
Declaration: This manuscript is original work and has not been submitted or is not under consideration for publication elsewhere. All the authors have reviewed the manuscript and approved it before submission. None of the authors have any conflict of interest from publishing this work.
Name of Department and Institution where work was done: Department of Oncology, National Center for Cancer Care & Research, Hamad Medical Corporation, Doha, Qatar