Table 2.

Details of the centers equipment and techniques.

	Center 1	Center 2
CT scanner	Toshiba Acquilion or GE LightSpeed-RT or Siemens Confidence	Philips Brilliance Big Bore
MRI scanner	Siemens Magnetom Skyra 3T	Siemens Magnetom Skyra 3T
Treatment planning system	Varian Eclipse	Philips Pinnacle
Record and verify system	Varian Aria	Elekta Mosaiq
Linear accelerators	Varian Clinac or Truebeam	Elekta Synergy (Agility MLC) or Versa
Fiducial markers	1.0 × 3.0 mm gold	1.2 × 3.0 mm gold
Treatment technique	7-field IMRT (n = 11) 2-arc VMAT (n = 4)	1-arc VMAT (n = 12) 2-arc VMAT (n = 3)
Prescribed dose	60 Gy in 20 fractions (n = 14) 78 Gy in 39 fractions (n = 1)	60 Gy in 20 fractions (n = 9) 78 Gy in 39 fractions (n = 6)
Beam energy	6 MV (n = 13) 10 MV (n = 2)	6 MV