Correction to: British Journal of Cancer (2015) 112, 562–566. doi:10.1038/bjc.2014.643; published online 23 December 2014

Updated online 26 May 2016: This article was originally published under a CC BY-NC-SA 4.0 license, but has now been made available under a CC BY 4.0 license. The PDF and HTML versions of the paper have been modified accordingly.