Table 2.

Dose volume parameters for planning target volumes and organs at risk.

Characteristics	VMAT median (range)	HT median (range)	p value
PTV45, Gy
Dmax	53.9 (52.2–59.2)	48.4 (47.1–49.8)	0.001
Dmin	38.8 (30.7–43.3)	37.5 (19.4–43.7)	0.81
Dmean	49.2 (48.1–52.1)	45.8 (45.6–46.1)	<0.001
PTV54, Gy
Dmax	64.3 (61.9–69.9)	57.8 (56.2–59.2)	<0.001
Dmin	46.8 (37.2–52.1)	45.4 (26.7–51.7)	0.65
Dmean	58.6 (56.3–61.9)	55.0 (54.7–55.2)	0.001
Ipsilateral lung
Mean dose, Gy	38.2 (20.8–51.4)	33.5 (18.0–40.1)	0.007
V5 (%)	100 (96.2–100)	99.7 (98.0–100)	0.59
V10 (%)	100 (77.2–100)	95.1 (68.2–100)	0.028
V20 (%)	92.0 (43.6–100)	80.2 (41.2–100)	0.10
Contralateral lung
Mean dose, Gy	11.8 (5.2–18.1)	6.7 (5.3–8.1)	0.018
V5 (%)	67.8 (33.2–90.0)	30.6 (21.4–49.0)	0.001
V10 (%)	51.4 (3.9–100)	29.6 (11.9–49.0)	0.009
V20 (%)	3.5 (0–55.0)	0.5 (0–14.3)	0.002
Total lung
Mean dose, Gy	19.8 (17.8–33.0)	16.1 (10.5–24.4)	0.003
V20 (%)	36.2 (25–69.0)	29.3 (13.08–45.5)	0.021
Spinal cord, Gy
Dmax	39.3 (31.9–44.2)	33.2 (22.5–34.2)	0.005
Heart
Mean dose, Gy	33.3 (12.1–54.9)	25.8 (7.3–45.7)	0.006
V25 (%)	57.9.0 (7.21–100)	43.5 (4.1–95.3)	0.002
V30 (%)	50.9 (4.45–100)	34.8 (1.4–88.9)	0.001
Mean kidney dose, Gy
Ipsilateral	2.5 (1.3–11.2)	1.6 (0.7–6.4)	0.28
Contralateral	1.9 (0.3–8.9)	2.0 (0.2–5.2)	0.27
Liver
Mean dose, Gy	13.1 (6.3–33.6)	15.1 (8.3–31.4)	0.31
V30 (%)	11.0 (0.0–59.2)	13.3 (0–50.8)	0.67
Esophagus
Dmean	38.6 (16.2–57.8)	29.9 (8.3–44.2)	0.001
V35	57.2 (0.9–100)	42.3 (0–100)	0.017
V50	40.3 (0–98.9)	29.6 (0–97)	0.024
Dosimetric indices
Conformity index	0.96 (0.93–0.99)	0.98 (0.97–0.99)	0.74
Homogeneity index	1.1 (1.1–1.1)	1.036 (1.03–1.05)	<0.001
Treatment duration
Monitor units, per fr	529 (471–765)	6590 (6185–7116)	<0.001
Treatment time (min/fr)	2.5 (2.1–3.0)	7.4 (6.9–7.8)	<0.001

PTV: planning target volume; V_X: volume receiving X Gy; D_max: maximum dose; D_min: minimum dose; D_mean: mean dose; fr: fraction.