Table 4 Univariate and multivariate analyses of the association of clinical and treatment-related factors with overall survival

Age in years

0.395

 Median 64,9

 <65

75 (50.3)

17 (14–20)

 ≥ 65

74 (49.7)

20 (14–26)

Sex

0.895

 Female

55 (36.9)

18 (11–25)

 Male

94 (63.1)

17 (13–22)

Smoking status

0.018

 Nonsmoker

24 (16.1)

60 (NA)

Ref.

 Former smoker

37 (24.8)

18 (12–25)

1.58 (0.75–3.34)

0.228

 Current smoker

77 (51.7)

14 (9–19)

2.02 (1.04–3.92)

0.037

 Unknown

11 (7.4)

17 (3–31)

1.62 (0.60–4.34

0.339

ECOG performance status

0.015

 0

24 (16.1)

20 (6–35)

Ref.

 1

102 (68.5)

19 (14–23)

0.75 (0.41–1.38)

0.356

 2

23 (15.4)

11 (8–13)

0.74 (0.33–1.65)

0.460

Stage

0.008

 I–II

37 (24.8)

29 (0–96)

Ref

 III

60 (40.3)

17 (14–20)

1.29 (0.69–2.41)

0.423

 IVa

35 (23.5)

17 (6–28)

1.17 (0.61–2.25)

0.629

 IVb

17 (11.4)

15 (7–22)

1.36 (0.63–2.96)

0.437

Histology

0.874

 Squamous cell carcinoma

126 (84.6)

17 (13–21)

 Other

23 (15.4)

20 (15–27)

BMI

0.164

 Median 22.8 (range 13.3–42.6)

 <20

34 (22.8)

9 (0–18)

 20–24.99

65 (43.6)

18 (15–21)

 >25

48 (32.9)

23 (6–40)

Weight loss >10% before chemoradiation

0.136

 Yes

79 (53.0)

13 (9–18)

 No

70 (47.0)

21 (17–25)

Completion of chemotherapy

0.028

 Yes

100 (67.1)

19 (16–23)

 No

49 (32.9)

12 (7–18)

0.70 (0.45–1.09)

0.116

Surgery

<0.0001

 Yes

64 (43.0)

60 (12–108)

0.28 (0.17–0.44)

<0.0001

 No

85 (57.0)

10 (7–13)

Radiation modality

0.531

 3D CRT

22 (14.8)

19 (6–31)

 IMRT

56 (37.6)

17 (15–19)

 VMAT

70 (47.0)

17 (8–26)

Radiation dose, Gy

0.422

 41.4

30 (20.1)

23 (16–30)

 45

39 (26.2)

19 (5–33)

 50–50.4

49 (32.9)

17 (13–21)

 54–60

23 (15.4)

15 (2–28)

 61–70

8 (5.4)

26 (13–39)

PTV, cm³

0.038

 Median 555 (range 121–1821)

 <555

75 (50.3)

22 (18–27)

Ref.

 ≥555

74 (49.7)

14 (7–20)

1.00 (0.99–1.00)

0.456

Mean lung dose, Gy

0.040

 Median 10,1 (range 4,0–21,8)

 <10

71 (49.0)

23 (18–28)

Ref.

 ≥10

74 (51.0)

12 (7–17)

1.05 (0.99–1.12)

0.116

Lung V5, %

0.182

 Median 55.6 (range 12.0-98.4)

 <55

71 (49.0)

21 (17–26)

 ≥55

74 (51.0)

14 (7–20)

Lung V20, %

0.052

 Median 14.6 (range 2.2-49.1)

 <15

77 (53.1)

23 (17–29)

 ≥15

68 (46.9)

13 (7–20)

Mean heart dose, Gy

0.922

 Median 17.9 (range 0.2-37.5)

 <18

72 (50.0)

19 (15–23)

 ≥18

72 (50.0)

15 (8–21)

Heart V30, %

0.607

 Median 16.5 (range 0.0–85.9)

 <17

73 (50.3)

20 (15–25)

 ≥17

72 (49.7)

14 (7–21)

Local recurrence

<0.0001

 Yes

59

15 (10–20)

0.74 (0.48–1.14)

0.722

 No

90

23 (7–38)

Ref.