Table 4.
Univariable and multivariable Cox proportional hazards regression models for PFS and OS in the validating set (Cohort 2: dMMR/MSI-high mGC)
| Characteristics | PFS | OS | ||||||
| Univariable | Multivariable | Univariable | Multivariable | |||||
| HR (95% CI) | P value | HR (95% CI) | P value | HR (95% CI) | P value | HR (95% CI) | P value | |
| Sex | 0.643 | 0.870 | ||||||
| Female | Ref | Ref | ||||||
| Male | 0.84 (0.41 to 1.73) | 0.94 (0.41 to 2.11) | ||||||
| Age | 0.695 | 0.483 | ||||||
| <70 | Ref | Ref | ||||||
| ≥70 | 0.87 (0.44 to 1.73) | 0.76 (0.35 to 1.65) | ||||||
| Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) | 0.018 | 0.410 | 0.022 | 0.301 | ||||
| 0 | Ref | Ref | Ref | Ref | ||||
| ≥1 | 2.94 (1.20 to 7.18) | 1.54 (0.55 to 4.31) | 3.49 (1.20 to 10.2) | 1.84 (0.58 to 5.88) | ||||
| Primary tumor resection | 0.003 | 0.133 | 0.009 | 0.066 | ||||
| No | Ref | Ref | Ref | Ref | ||||
| Yes | 0.30 (0.13 to 0.66) | 0.46 (0.17 to 1.27) | 0.30 (0.12 to 0.74) | 0.37 (0.13 to 1.07) | ||||
| Primary site of origin | 0.353 | 0.419 | ||||||
| Gastroesophageal junction (GEJ) | Ref | Ref | ||||||
| Gastric | 0.60 (0.21 to 1.75) | 0.60 (0.18 to 2.05) | ||||||
| Histology | 0.506 | 0.575 | ||||||
| Intestinal | Ref | Ref | ||||||
| Diffuse/other | 1.29 (0.61 to 2.71) | 1.27 (0.56 to 2.93) | ||||||
| Synchronous metastases | 0.460 | 0.855 | ||||||
| No | Ref | Ref | ||||||
| Yes | 1.33 (0.63 to 2.81) | 0.93 (0.42 to 2.06) | ||||||
| Liver metastases | 0.294 | 0.201 | ||||||
| No | Ref | Ref | ||||||
| Yes | 0.60 (0.23 to 1.56) | 0.46 (0.14 to 1.52) | ||||||
| Lymphnodal metastases | 0.767 | 0.947 | ||||||
| No | Ref | Ref | ||||||
| Yes | 1.14 (0.49 to 2.62) | 0.97 (0.39 to 2.42) | ||||||
| Lung metastases | 0.789 | 0.802 | ||||||
| No | Ref | Ref | ||||||
| Yes | 0.88 (0.34 to 2.28) | 0.87 (0.30 to 2.53) | ||||||
| Bone metastases | 0.039 | 0.065 | 0.057 | |||||
| No | Ref | Ref | Ref | |||||
| Yes | 3.13 (1.06 to 9.27) | 2.94 (0.94 to 9.20) | 3.36 (0.98 to 11.64) | |||||
| No of metastatic sites | 0.175 | 0.165 | ||||||
| 1 | Ref | Ref | ||||||
| ≥2 | 1.74 (0.78 to 3.87) | 1.92 (0.76 to 4.80) | ||||||
| Prior treatment for metastatic disease | 0.792 | 0.719 | ||||||
| No | Ref | Ref | ||||||
| Yes | 0.87 (0.30 to 2.48) | 0.80 (0.24 to 2.68) | ||||||
| ICI regimen | 0.722 | 0.908 | ||||||
| a-PD-1 | Ref | Ref | ||||||
| a-PD-1 +chemotherapy | 0.77 (0.18 to 3.24) | 1.10 (0.27 to 4.63) | ||||||
| Peritoneal metastases | <0.001 | 0.005 | 0.006 | 0.023 | ||||
| No | Ref | Ref | Ref | Ref | ||||
| Yes, without ascites | 1.48 (0.55 to 4.02) | 1.87 (0.64 to 5.46) | 1.69 (0.55 to 5.18) | 2.15 (0.64 to 7.27) | ||||
| Yes, with ascites | 4.57 (2.07 to 10.09) | 3.83 (1.68 to 8.72) | 4.18 (1.70 to 10.26) | 3.44 (1.39 to 8.53) | ||||
P-values marked with bold indicate statistically significant p-values.
dMMR, mismatch repair deficient; ICIs, immune checkpoint inhibitors; mGC, metastatic gastric cancer; MSI, microsatellite instability; OS, overall survival; PFS, progression-free survival.