Table 1 Basic characteristics

Total patients/LO number

70/144

Sex(male/female)

37(52.9%)/33(47.1%)

Age (mean ± SD, years old)

57.5 ± 7.6

BMI (mean ± SD, mg/m²)

24.6 ± 2.9

Serum CEA (mean ± SD, ng/ml)

28.7 ± 21.8

Serum CEA stratification (≤ 15 ng/ml/ > 15 ng/ml)

32(45.7%)/38(54.3%)

Primary tumor site (colon/rectum)

34(48.6%)/36(51.4%)

Pathological classification (low/middle- high differentiated)

28(40.0%)/42(60.0%)

TNM stage (stage I-III/stage IV)

47(67.1%)/23(32.9%)

ECOG score (0/1)

35(50.0%)/35(50.0%)

Number of LO per person(1/2/3/4/5 LO)

26(37.1%)/21(30.0%)/17(24.3%)/5(7.1%)1(1.4%)

Mean number of LO per person ( mean ± SD)

2.1 ± 1.0

Number of LO stratification (≤ 2 / > 2 nodules)

47(67.1%)/23(32.9%)

LO location (left/right lung)

79(54.9%)/65(45.1%)

Mean GTV per LO ( mean ± SD, cm³)

31.2 ± 18.1

Cumulative GTV per person ( cm³)

53.0 ± 22.4

Cumulative GTV stratification (≤ 40 / > 40 cm³)

31(44.3%)/39(55.7%)

D90 per LO (mean ± SD, Gy)

116.4 ± 11.8

Systemic treatments (C + TT/C alone)

43(61.4%)/27(38.6%)

Progression disease (Yes/no)

64(91.4%)/6(8.6%)

Disease-free interval (months)

11.0 ± 6.9

Disease-free interval stratification (≤ 12 / > 12 months)

47(67.1%)/23(32.9%)

Disease progression type (local/regional/distance failure)

9/22/61

PFS (median, 95% CI) (months)

10.0(95% CI: 8.9–11.1)

6-, 12-, 24-month PFS rates (%)

72.9%/32.9%/5.9%

OS (median, 95% CI) (months)

30.8(95% CI: 27.1–34.4)

1-, 2-, 3-year OS rates (%)

95.7%/67.4%/42.5%