Table 1 Association between clinicopathologic factors and the expression of programmed cell death-ligand 1 (PD-L1) and programmed cell death-ligand 2 (PD-L2) in primary tumors and metastatic lymph nodes from patients with gastric adenocarcinoma
Variable | Total (cases) | PD-L1 expression [cases (%)] | PD-L2 expression [cases (%)] | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Primary tumors | Metastatic lymph nodes | Primary tumors | Metastatic lymph nodes | ||||||||||
Negative | Positive | P | Negative | Positive | P | Negative | Positive | P | Negative | Positive | P | ||
Total | 119 | 73 | 46 | Â | 65 | 54 | Â | 85 | 34 | Â | 87 | 32 | Â |
Sex | Â | Â | 0.102 | Â | 0.352 | Â | 0.904 | Â | 0.991 | ||||
 Male | 78 | 52 (66.7) | 26 (33.3) |  | 45 (57.7) | 33 (42.3) |  | 56 (71.8) | 22 (28.2) |  | 57 (73.1) | 21 (26.9) |  |
 Female | 41 | 21 (51.2) | 20 (48.8) |  | 20 (48.8) | 21 (51.2) |  | 29 (70.7) | 12 (29.3) |  | 30 (73.2) | 11 (26.8) |  |
Age (years) | Â | Â | Â | 0.781 | Â | Â | 0.450 | Â | Â | 0.911 | Â | Â | 0.122 |
 <55 | 55 | 33 (60.0) | 22 (40.0) |  | 28 (50.9) | 27 (49.1) |  | 39 (70.9) | 16 (29.1) |  | 44 (80.0) | 11 (20.0) |  |
 ≥55 | 64 | 40 (62.5) | 24 (37.5) |  | 37 (57.8) | 27 (42.2) |  | 46 (71.9) | 18 (28.1) |  | 43 (67.2) | 21 (32.8) |  |
Tumor location | Â | Â | Â | 0.289 | Â | Â | 0.878 | Â | Â | 0.537 | Â | Â | 0.552 |
 Cardia | 49 | 34 (69.4) | 15 (30.6) |  | 28 (57.1) | 21 (42.9) |  | 37 (75.5) | 12 (24.5) |  | 38 (77.6) | 11 (22.4) |  |
 Body | 20 | 12 (60.0) | 8 (40.0) |  | 11 (55.0) | 9 (45.0) |  | 15 (75.0) | 5 (25.0) |  | 15 (75.0) | 5 (25) |  |
 Antrum | 50 | 27 (54.0) | 23 (46.0) |  | 26 (52.0) | 24 (48.0) |  | 33 (66.0) | 17 (34.0) |  | 34 (68.0) | 16 (32.0) |  |
Cell differentiation | Â | Â | Â | 0.952 | Â | Â | 0.822 | Â | Â | 0.114 | Â | Â | 0.202 |
 Well to moderate | 21 | 13 (61.9) | 8 (38.1) |  | 11 (52.4) | 10 (47.6) |  | 12 (57.1) | 9 (42.9) |  | 13 (61.9) | 8 (38.1) |  |
 Poor (including Signet ring cell) | 98 | 60 (61.2) | 38 (38.8) |  | 54 (55.1) | 44 (44.1) |  | 73 (74.5) | 25 (25.5) |  | 74 (75.5) | 24 (24.5) |  |
Lauren classification | Â | Â | Â | 0.032 | Â | Â | 0.028 | Â | Â | 0.119 | Â | Â | 0.005 |
 Intestinal | 60 | 31 (51.7) | 29 (48.3) |  | 27 (45.0) | 33 (55.0) |  | 39 (65.0) | 21 (35.0) |  | 37 (61.7) | 23 (38.3) |  |
 Diffuse and mixed | 59 | 42 (71.2) | 17 (28.8) |  | 38 (64.4) | 21 (35.6) |  | 46 (78.0) | 13 (22.0) |  | 50 (84.7) | 9 (15.3) |  |
Vascular invasion | Â | Â | Â | 0.011 | Â | Â | 0.009 | Â | Â | 0.011 | Â | Â | 0.003 |
 Yes | 55 | 27 (49.1) | 28 (50.9) |  | 23 (41.8) | 32 (58.2) |  | 33 (60.0) | 22 (40.0) |  | 33 (60.0) | 22 (40.0) |  |
 No | 64 | 46 (71.9) | 18 (28.1) |  | 42 (65.6) | 22 (34.4) |  | 52 (81.3) | 12 (18.8) |  | 54 (84.4) | 10 (15.6) |  |
Neural invasion | Â | Â | Â | 0.381 | Â | Â | 0.679 | Â | Â | 0.001 | Â | Â | 0.004 |
 Yes | 77 | 45 (58.4) | 32 (41.6) |  | 41 (53.2) | 36 (46.8) |  | 63 (81.8) | 14 (18.2) |  | 63 (81.8) | 14 (18.2) |  |
 No | 42 | 28 (66.7) | 14 (33.3) |  | 24 (57.1) | 18 (42.9) |  | 22 (52.4) | 20 (47.6) |  | 24 (57.1) | 18 (42.9) |  |
Clinical stage | Â | Â | Â | 0.099 | Â | Â | 0.377 | Â | Â | 0.336 | Â | Â | 0.400 |
 II–IIIA | 12 | 10 (83.3) | 2 (16.7) |  | 8 (66.7) | 4 (33.3) |  | 10 (83.3) | 2 (16.7) |  | 10 (83.3) | 2 (16.7) |  |
 IIIB–IIIC | 107 | 63 (58.9) | 44 (41.1) |  | 57 (53.3) | 50 (46.7) |  | 75 (70.1) | 32 (29.9) |  | 77 (72.0) | 30 (28.0) |  |