Table 3 Univariate analysis of local tumor control and overall survival (log rank of Kaplan-Meier method)

Gender

Male

32

1.054

0.305

2.671

0.102

Female

11

Age

≤70

23

0.832

0.362

0.116

0.733

>70

20

Karnofsky performance status

70

7

1.584

0.453

1.769

0.413

80

19

90

17

Comorbidities

Yes

33

0.442

0.506

0.007

0.932

No

10

Type

Central

8

0.427

0.514

0.173

0.678

Periphery

35

Histology

Squamous cell carcinoma

17

0.696

0.874

0.975

0.807

Adenocarcinoma

14

Adenosquamouscarcinoma

1

Unspecified

11

Clinical stage

I

23

14.888

0.000

7.926

0.005

II

20

Tumor size

≤3 cm

4

12.824

0.005*

5.361

0.147

3-5 cm

20

5-7 cm

10

>7 cm

9

Dose/fraction

(50% isodose line)

<6Gy

27

1.337

0.248

0.979

0.322

≥6Gy

16

BED (50% isodose line)

<60Gy

17

0.550

0.458

0.033

0.856

≥60Gy

26

Chemotherapy

no

30

2.194

0.139

6.000

0.014

yes

13