Table 1.

Patient, treatment, and scan characteristics

	Parameter total (N)	Parameter total (%)	Symptomatica (N)	Symptomatica (%)	p‐valueb
No of patients	96	100%	18	19%	N/A
Gender					0.74
Male	83	86%	16	19%
Female	13	14%	2	15%
Median age (range)	62 yrs (29–81) yrs	N/A	65.5 yrs (48.8–81) yrs	N/A	0.27
Histology					0.005c
Adenocarcinoma	80	83%	11	14%
Squamous cell carcinoma	13	14%	5	38%
Neuroendocrine	2	2%	1	50%
Sarcoma	1	1%	1	100%
Sum of Squamous, Neuroendocrine, Sarcoma	16	17%	7	44%
Smoking history					0.55
Current	13	14%	1	8%
Former	64	67%	13	20%
Never	19	20%	4	21%
Tumor location					0.43d
Distal	56	58%	9	16%
GEJ	27	28%	4	15%
Middle	11	11%	4	36%
Proximal	2	2%	1	50%
Sum of GEJ, middle, proximal	40	42%	9	23%
Treatment modality					0.77
IMRT	55	57%	9	16%
3D‐CRT	17	18%	4	24%
Proton	24	25%	5	21%
Treatment dose parameters
Median prescribed dose (range)	50.4 Gy (36–59.4) Gy	N/A	50.4 Gy (45–50.4) Gy	N/A	0.30
Median number of fractions (range)	28 (12–30)	N/A	28 (25–28)	N/A	0.37
Median MLD (range)	10.0 Gy (1.6–18.3) Gy	N/A	11.3 Gy (1.6–15.7) Gy	N/A	0.10
Median lung V20% (range)	17.6% (3.5–34.8) %	N/A	20.9% (3.6–32.3) %	N/A	0.16
Median interval between diagnostic CT scan and treatment
Pre‐treatment scan to RT start (range)	25 days (0–45) days	N/A	13 days (7–41) days	N/A	0.03
Post‐treatment scan from RT end (range)	38 days (21–75) days	N/A	40 days (21–75) days	N/A	0.07
Pre‐ and post‐therapy CT scan parameters (N = 192)
Kilovoltage = 120 kVp	189
Kilovoltage = 140 kVp	3
Average slice thickness (range)	2.5 mm (2.0–4.0) mm
Average in‐plane pixel resolution (range)	0.79 mm (0.66–0.98) mm
Incidence of RP
Grade 0	36	38%
Grade 1	42	44%
Grade 2	10	10%
Grade 3	5	5%
Grade 4	2	2%
Grade 5	1	1%

^aSymptomatic RP grade ≥ 2.

^bSignificance assessed at P < 0.01 using Chi‐squared or Mann–Whitney tests.

^cAdenocarcinoma versus sum of Squamous, Neuroendocrine, Sarcoma.

^dDistal versus sum of GEJ, Middle, Proximal.