Table 2.
Summary of the pooled OR
| Studies | Overall OR (95 % CI) | I2; p | P value | Cases | Controls | p (Egger’s test) | |
|---|---|---|---|---|---|---|---|
| Cancer vs. Normal | 10 | 6.18 (4.02–9.51) | 0.0 %; 0.679 | <0.001 | 706 | 429 | 0.197 |
| Subgroup | |||||||
| Sample type | |||||||
| Blood | 2 | 18.71 (2.41–145.20) | 39.6 %; 0.198 | 0.005 | 55 | 82 | |
| Tissue | 9 | 5.74 (3.68–8.95) | 0.0 %; 0.818 | < 0.001 | 651 | 347 | |
| Race | |||||||
| Caucasians | 5 | 5.39 (3.25–8.94) | 0.0 %; 0.981 | < 0.001 | 294 | 155 | |
| Asians | 5 | 8.34 (3.63–19.13) | 40.1 %; 0.154 | < 0.001 | 567 | 274 | |
| Cancer vs. Benign | 7 | 3.26 (1.65–6.44) | 0.0 %; 0.938 | 0.001 | 431 | 109 | 0.172 |
| Cancer vs. LMP | 5 | 1.30 (0.67–2.51) | 0.0 %; 0.663 | 0.436 | 319 | 75 | 0.199 |
| Clinicopathological features | Cancer patients | ||||||
| Low-grade | High-grade | ||||||
| Tumor grade | 4 | 0.46 (0.13–1.65) | 68.5 %; 0.013 | 0.233 | 116 | 148 | 0.488 |
| StageI-II | Stage III-IV | ||||||
| Tumor stage | 5 | 0.76 (0.31–1.88) | 61.0 %; 0.025 | 0.558 | 188 | 278 | 0.449 |
| Serous carcinoma | Non-serous carcinoma | ||||||
| Tumor histology | 7 | 0.56 (0.35–0.91) | 0.0 %; 0.584 | 0.02 | 193 | 217 | 0.238 |
LMP low malignant potential tumor, OR odds ratio, 95 % CI 95 % confidence interval