Table 1 Patient and tumor characteristics according to ctDNA at diagnosis

Sex

<0.001

 Female

22 (31%)

6 (100%)

16 (25%)

 Male

48 (69%)

0 (0%)

48 (75%)

Age (years, median, IQR)

60 (52, 69)

63 (60, 71)

59 (52, 69)

0.4

ECOG PS

>0.9

 0

24 (34%)

2 (33%)

22 (34%)

 1

46 (66%)

4 (67%)

42 (66%)

Primary tumor site

>0.9

GEJ

38 (54%)

3 (50%)

35 (55%)

Stomach

32 (46%)

3 (50%)

29 (45%)

Tumor subtype^b

>0.9

 Diffuse

28 (40%)

3 (50%)

25 (39%)

 Intestinal

36 (51%)

3 (50%)

33 (52%)

 Other

6 (8.6%)

0 (0%)

6 (9.4%)

Resection of primary tumor

20 (29%)

3 (50%)

17 (27%)

0.3

Type of disease

0.30

 Locally advanced

4 (6%)

1 (17%)

3 (5%)

 Metastatic

66 (94%)

5 (83%)

61 (95%)

Liver metastasis

28 (40%)

1 (17%)

27 (42%)

0.4

Lung metastasis

53 (80%)

5 (100%)

48 (78%)

0.6

Peritoneal carcinomatosis

22 (33%)

4 (80%)

18 (29%)

0.07

Lymph node metastasis

31 (47%)

0

31 (51%)

0.03

Time to metastatic disease

0.09

 Metachronous

23 (33%)

4 (67%)

19 (30%)

 Synchronous

47 (67%)

2 (33%)

45 (70%)

LDH (times normal)

0.95 (0.74, 1.15)

0.80 (0.64, 1.03)

0.95 (0.77, 1.15)

0.5

 Unknown

6

2

4

ALP (times normal)

0.99 (0.72, 1.42)

1.12 (1.00, 1.39)

0.95 (0.70, 1.43)

0.3

 Unknown

1

1

0

NLR

0.19 (0.14, 0.26)

0.33 (0.31, 0.36)

0.19 (0.14, 0.23)

0.001

 Unknown

1

1

0

HER2 status

 Positive

17 (24%)

0 (0%)

17 (27%)

 Negative

53 (76%)

6 (100%)

47 (73%)

0.3

 Unknown

1

1

0

CPS PD-L1

0.12

 CPS ≥ 5

17 (35%)

3 (75%)

14 (32%)

 CPS < 5

31 (65%)

1 (25%)

30 (68%)

 Unknown

22

2

20

TPS PD-L1

0.06

 TPS ≥ 1

13 (27%)

3 (75%)

10 (23%)

 TPS < 1

35 (73%)

1 (25%)

34 (77%)

 Unknown

22

2

20