Jochem van der Voort van Zijp, MD, Department of Radiation Oncology, Leiden University Medical Center, Postbus 9600, Leiden RC 2333, The Netherlands. j.r.n.van_der_voort_van_zijp@lumc.nl
Article-Type of This Article
Review
Open-Access Policy of This Article
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/