Table 1.

Maximum motion of structures in 3 directions

	Mean ± SD, cm (range)
Structure	Left-right (X)	Anterior-posterior (Y)	Superior-inferior (Z)
GTV (n = 24)	0.23 ± 0.15 (0.03-0.68)	0.32 ± 0.31 (0.03-1.54)	0.79 ± 0.58 (0.06-1.95)
Fiducial centroid (n = 24)	0.20 ± 0.20 (0.03-0.95)	0.35 ± 0.29 (0.08-1.51)	0.78 ± .57 (0.1-2.0)
RPM block (n = 11)		0.51 ± 0.28 (0.10-1.02)

Abbreviations: GTV = gross tumor volume; RPM = real-time position management; SD = standard deviation.

The RPM block excursions were only measured in the anterior-posterior direction. Patients from the validation cohort (n = 4) were not included in this analysis.