Table 1 Baseline characteristics

n

43

31

Sex

Male

32 (74.4)

22 (71.0)

Age, years

57 (50–63)

57 (50–62)

ECOG PS score

1

9 (20.9)

6 (19.4)

Tumor differentiation

Good

1 (2.3)

0 (0.0)

Moderate

13 (30.2)

11 (35.5)

Moderate-poor

17 (39.5)

13 (41.9)

Poor

12 (27.9)

7 (22.6)

Tumor location

Pancreas head

11 (25.6)

11 (35.5)

Pancreas body

8 (18.6)

3 (9.7)

Pancreas tail

22 (51.2)

15 (48.4)

Pancreas body and tail

2 (4.7)

2 (6.5)

Liver metastasis

Yes

40 (93.0)

30 (96.8)

Lung metastasis

Yes

8 (18.6)

4 (12.9)

Bone metastasis

Yes

12 (27.9)

10 (32.3)

Distant lymph node metastasis

Yes

19 (44.2)

13 (41.9)

Number of metastases

≥ 2

30 (70.0)

20 (64.5)

Baseline CA19-9 level, U/mL

4527.0 (932.2–16,580.0)

3488.5 (900.1–11,563.5)

Abnormal

39 (90.7)

28 (90.3)

≥ 2000

25 (58.1)

17 (54.8)

Best CA19-9 change, U/mL

− 60.8 (− 94.7 to − 16.7)

− 60.8 (− 94.3 to − 16.7)

< 0

35 (81.4)

25 (80.7)

> 50% decline from baseline

18 (41.9)

14 (45.2)

Baseline CEA level, µg/L

21.0 (10.1–41.0)

22.6 (10.9–42.1)

Abnormal

28 (65.1)

20 (64.5)

Best CEA change, µg/L

− 17.5 (− 63.6 to 143.4)

24.3 (− 62.6 to 168.2)

< 0

31 (72.1)

20 (64.5)

Baseline CA125 level, U/mL

138.0 (72.5–488.2)

136.2 (77.5–346.3)

Abnormal

30 (69.8)

22 (71.0)

Best CA125 change, U/mL

− 33.8 (− 68.2 to 45.8)

− 17.4 (− 66.1 to 53.8)

< 0

34 (79.1)

23 (74.2)

Cycle of chemotherapy

4 (3–6)

4 (3–6)

Best objective response

Partial response

19 (44.2)

14 (45.2)

Stable disease

14 (32.6)

11 (35.5)

Progressive disease

10 (23.3)

6 (19.4)

S-1 maintanence

Yes

13 (30.2)

8 (25.8)

Cycle of S-1

2 (2–9)

3 (2–7)

Overall survival, months

Median

9.8 (8.6–NE)

10.0 (9.1–NE)

≥ 6

34 (79.1)

25 (80.7)

≥ 12

21 (48.8)

16 (51.6)

Progression-free survival, months

Median

5.9 (4.4–7.4)

6.1 (4.8–8.6)

≥ 6

21 (48.8)

17 (54.8)

≥ 12

10 (23.3)

8 (25.8)