Table 6 Overall progression-free survival for the entire cohort stratified by duration of follow-up

Duodenal invasion

 Yes

13

3.69 (2.6–4.8)

0.03*

11

7.73 (5.9–9.5)

0.35

17

17 (14.5–19.5)

0.10

12

59.66 (44.7–74.7)

 No

16

2.44 (1.9–2.9)

5

9 (7.0–10.9)

13

14.46 (12.9–16.0)

10

39.4 (23.2–55.6)

0.05*

Age

 ≤ 60

7

3.71 (2.7–4.7)

0.16

2

9 (3.7–21.7)

0.60

9

15 (11.7–18.3)

0.45

8

54.1 (28.9–79.3)

  > 60

22

2.77 (2.1–3.5)

14

8 (6.5–9.5)

21

16.28 (14.4–18.2)

14

48.4 (35.5–61.2)

0.62

Lymphovascular invasion

 Yes

21

3.09 (2.3–3.9)

0.59

14

8.28 (6.8–9.8)

0.5

20

15.45 (13.4–17.5)

0.42

15

55.6 (40.4–70.8)

0.16

 No

8

2.75 (1.8–3.7)

2

7 (7–7)

10

16.8 (14.1–19.5)

7

39.42 (26.3–52.5)

Perineural invasion

 Yes

25

3.12 (2.5–3.8)

0.30

13

8.31 (6.7–9.9)

0.54

24

15.6 (13.9–17.4)

0.55

20

52.35 (40.8–63.9)

0.27

 No

4

2.25 (0.1–4.6)

3

7.3 (5.9–8.8)

6

16.83 (11.8–21.9)

2

31.5 (17.5–202.56)

Lymph node involved

 Yes

22

3.04 (2.3–3.8)

0.78

14

8.21 (6.7–9.7)

0.71

21

16.09 (13.9–18.2)

0.70

14

53.07 (37.7–68.4)

0.52

 No

7

2.86 (2.0–3.7)

2

7.5 (1.1–13.9)

9

15.4 (13.10–17.8)

8

45.87 (27.1–64.6)

Mortality status

 Deceased

11

2.27 (1.3–3.3)

0.04*

8

8 (6.1–9.9)

0.84

7

15.29 (12.2–18.4)

0.66

6

35 (18.6–51.4)

0.07

 Alive

18

3.4 (2.7–4.2)

8

8.25 (6.0–10.5)

23

16.08 (14.2–18.0)

16

56.3 (42.6–69.9)