Baseline characteristics of the patients with gastric carcinoma received ICB therapy
| Characteristics | EBV+/pMMR (n=22) | EBV−/pMMR (n=44) | EBV−/dMMR (n=29) | P value: EBV+/pMMR versus EBV−/pMMR | P value: EBV+/pMMR versus EBV−/dMMR |
| Age Median (range) | 63.5 (28–74) | 59.0 (24–77) | 65.0 (32–82) | 0.320 | 0.266 |
| EBV status by EBER | |||||
| Positive | 22 | 2 | 0 | 0.000 | 0.000 |
| Negative | 0 | 36 | 23 | ||
| Sex | |||||
| Male | 18 | 31 | 19 | 0.384 | 0.225 |
| Female | 4 | 13 | 10 | ||
| Stage | |||||
| III | 1 | 0 | 4 | 0.333 | 0.375 |
| IV | 21 | 44 | 25 | ||
| Prior systemic therapy | |||||
| Yes | 13 | 43 | 23 | 0.000 | 0.135 |
| No | 9 | 1 | 6 | ||
| ICB strategy | |||||
| Mono-ICB | 8 | 43 | 25 | 0.000 | 0.000 |
| Dual-ICB | 14 | 1 | 4 | ||
| PD-L1 (CPS >1) | |||||
| Positive | 15 | 19 | 13 | 0.115 | 1.000 |
| Negative | 7 | 23 | 7 | ||
| HER2 IHC staining | |||||
| 0 | 16 | 26 | 18 | 0.088 | 0.906 |
| 1 | 4 | 3 | 7 | ||
| 2 | 1 | 13 | 2 | ||
| 3 | 1 | 2 | 1 | ||
CPS, combined positive score; dMMR, mismatch repair deficient; Dual-ICB, combination anti-CTLA-4 plus anti-PD-1/L1 therapy; EBER, Epstein-Barr virus-encoded small RNA; EBV, Epstein-Barr virus; HER2, human epidermal growth factor receptor 2; ICB, immune checkpoint blockade; ICI, immune checkpoint inhibitor; IHC, immunohistochemistry; Mono-ICB, anti-PD-1/L1 monotherapy; PD-1, programmed death 1; PD-L1, programmed death-ligand 1; pMMR, mismatch repair proficient.