Optimization of Minimum Segment Width Parameter in the Intensity-Modulated Radiotherapy Plan for Esophageal Cancer

Figures & data

Table 1 Summary of Clinical and Image Characters

Characters	N (%)	Mean (SD)
Sex	20
Female	8 (40.0%)
Male	12 (60.0%)
Age (years)	20	67.3 (7.39)
Clinical stage	20
T2N2M0	2 (10.0%)
T3N1M0	16 (80.0%)
T3N2M0	2 (10.0%)
Local	20
Mid thorax	9 (45.0%)
Upper thorax	11 (55.0%)
Length (cm)	20	5.35 (1.60)
VPTV60 (cm^3)	20	137 (67.0)
VPTV51 (cm^3)	20	486 (106)
V Llung (cm^3)	20	1506 (457)
VRlung (cm^3)	20	1958 (764)

Abbreviations: V_PTV60, volume of PTV60; V_PTV51, volume of PTV51; V _Llung, volume of left lung; V_Rlung, volume of right lung.

Table 2 The Cost Functions of IMRT Planning for ESCC

ROIs	Cost Function	Parameter	Iso Constraint
PTV60	Target penalty	98%	60Gy
	Quadratic Overdose	63Gy	100
PTV51	Target penalty	98%	51Gy
	Quadratic Overdose	60Gy Shrink 0.1cm	30
	Quadratic Overdose	55Gy Shrink 0.6cm	100
Llung	Parallel	20Gy K=3	20
	Parallel	5Gy K=3	50
Rlung	Parallel	20Gy K=3	20
	Parallel	5Gy K=3	50
Spine cord	Maximum dose	NA	45Gy
Heart	Parallel	30Gy k=3	10
	Serial	K=3	20Gy
PTV51+1cm	Quadratic Overdose	51Gy Shrink 0.1cm	30
	Quadratic Overdose	48Gy Shrink 0.3cm	100
	Serial	K=14 Shrink 0.5cm	45Gy
Patent	Maximum dose	NA	66Gy
	Quadratic Overdose	30Gy Shrink 3cm	80
	Serial	K=14	35Gy

Note: PTV51+1cm: were defined as the PTV51 with a 1 cm margin in all directions.

Figure 1 Box plot (A) of the parameters of organ at risks (OARs). Forest plot (B) of the OARs between different MSW groups.

Figure 2 Box plot (A) of the HI and CI of PTV₆₀ and PTV₅₁. Forest plot (B) of HI and CI of the PTV₆₀ and PTV₅₁ between different MSW groups.

Figure 3 Box plot (A) and forest plot (B) of MU, CP and delivery time among different MSW groups.

Figure 4 Box plot (A) and forest plot (B) of GPR among different MSW groups.