Table 2. Results of overall and subgroup analyses for effects of LVI on overall and disease-free survival in colorectal cancer.
| Categories | N | Patients | Pooled HR(95 % CI) | P value | Heterogeneity | Model used | |
|---|---|---|---|---|---|---|---|
| I2 | P* | ||||||
| Overall survival (OS) | 9 | 2690 | 2.39(1.70-3.36) | <0.01 | 46 | 0.06 | FEM |
| Subgroup 1: Asian | 3 | 1460 | 2.70(1.27-5.73) | 0.01 | 82 | <0.01 | REM |
| Non-Asian | 6 | 1230 | 2.27(1.56-3.30) | <0.01 | 0 | 0.61 | REM |
| Subgroup 2: LVI positive rate >15 % | 5 | 1055 | 2.45(1.64-3.65) | <0.01 | 0 | 0.63 | REM |
| LVI positive rate ≤15 % | 4 | 1635 | 2.38(1.28-4.43) | <0.01 | 74 | <0.01 | REM |
| Subgroup 3: sample size>200 | 4 | 1952 | 2.33(1.37-3.96) | <0.01 | 71 | 0.02 | REM |
| Sample size≤200 | 5 | 738 | 2.63(1.68-4.10) | <0.01 | 0 | 0.47 | REM |
| Subgroup 4: colon cancer | 4 | 1186 | 2.99(2.08-4.31) | <0.01 | 6 | 0.36 | REM |
| Rectal cancer | 2 | 399 | 2.41(0.91-6.32) | 0.08 | 53 | 0.14 | REM |
| Colorectal cancer | 3 | 1105 | 1.64(1.10-2.43) | 0.02 | 10 | 0.33 | REM |
| Subgroup 5:study quality score>6 | 3 | 911 | 2.43(1.22-4.84) | 0.01 | 55 | 0.11 | REM |
| Study quality score≤6 | 6 | 1779 | 2.32(1.54-3.50) | <0.01 | 42 | 0.12 | REM |
| Disease-free survival (DFS) | 10 | 8438 | 1.73(1.50-1.99) | <0.01 | 6 | 0.38 | FEM |
| Subgroup 1: Asian | 8 | 3735 | 1.92(1.57-2.34) | <0.01 | 0 | 0.56 | FEM |
| Non-Asian | 5 | 4703 | 1.55(1.27-1.90) | <0.01 | 17 | 0.30 | FEM |
| Subgroup 2: LVI positive rate >15 % | 4 | 1485 | 1.91(1.34-2.72) | <0.01 | 17 | 0.30 | FEM |
| LVI positive rate ≤15 % | 9 | 6953 | 1.69(1.45-1.98) | <0.01 | 9 | 0.36 | FEM |
| Subgroup 3: sample size>200 | 10 | 8052 | 1.73(1.50-2.00) | <0.01 | 16 | 0.29 | FEM |
| Sample size≤200 | 3 | 386 | 1.66(0.72-3.83) | 0.24 | 4 | 0.35 | FEM |
| Subgroup 4: colon cancer | 5 | 2454 | 1.86(1.35-2.55) | <0.01 | 11 | 0.34 | REM |
| Rectal cancer | 2 | 2873 | 1.91(0.95-3.82) | 0.07 | 70 | 0.07 | REM |
| Colorectal cancer | 6 | 3111 | 1.64(1.39-1.94) | <0.01 | 0 | 0.51 | REM |
| Subgroup 5:study quality score>6 | 5 | 2266 | 2.09(1.57-2.77) | <0.01 | 0 | 0.57 | FEM |
| Study quality score≤6 | 7 | 3523 | 1.72(1.41-2.11) | <0.01 | 8 | 0.37 | FEM |
FEM fixed-effect model, REM random-effect model, HR hazard ratio, N number of studies, pCRT postoperative chemoradiotherapy, P* P value of Q test for heterogeneity test, 95%CI 95%confidence interval, LVI lymphovascular invasion