Accepted: 6 December 2019
First Online: 20 February 2020
: J.H.S. has acted as a consultant of AbbVie. R.K. has received honoraria from Accuray, Elekta AB, Elsevier and Novocure, and has served on the advisory board of Accuray and Novocure. S.T.C. has received honoraria from Varian Medical Systems. M.S.A. has acted as a consultant of AbbVie, Bayer, Elsevier, Flatiron, Karyopharm, Varian Medical Systems and VBI vaccines, has received royalties from Wiley, fees for contracted research from AbbVie, AstraZeneca, Bayer, BMS, Incyte, Merck, Novocure and Pharmacyclics, and owns stocks in Doctible and Mimivax. A.S. has acted as a consultant of AbbVie, BrainLAB, Elekta (Gamma Knife Icon), Merck, Roche and Varian, has served on the advisory board of VieCure and the International Stereotactic Radiosurgery Society (ISRS), has conducted educational seminars on behalf of Accuray, BrainLAB, Elekta AB and Varian (CNS Teaching Faculty), has received a research grant from Elekta AB, has received travel and accommodation fees from BrainLAB, Elekta and Varian, and is a member of the Elekta MR Linac, Elekta Spine, Oligometastases and Linac-based SRS consortia. E.L.C. declares no competing interests.