Background
Methods
Data sources, search strategy, and selection criteria
Data collection and quality assessment
Statistical analysis
Results
Literature search
Study characteristics
Study | Publication year | Country | Study design | Sample size | Mean age (years) | Disease stages | Treatment strategy | Cutoff value | Adjusted or not | Reported outcomes | NOS scale |
---|---|---|---|---|---|---|---|---|---|---|---|
Hernandez et al. [33] | 1992 | USA | Retrospective | 113 | 59.2 | I–IV | Radiation | 400 | Not | OS | 5 |
Lopes et al. [37] | 1994 | England | Retrospective | 643 | 45.5 | Ib–IV | Surgery or radiation | 400 | Not | OS | 7 |
Hernandez et al. [32] | 1994 | USA | Retrospective | 623 | NS | Ib | Surgery | 400 | Not | OS, PFS | 7 |
Rodriguez et al. [40] | 1994 | USA | Retrospective | 219 | 40.0 | Ib | Surgery | 300 | Not | OS | 5 |
De Jonge et al. [28] | 1999 | South Africa | Retrospective | 93 | NS | Ib | Surgery | 400 | Yes | OS, RFS | 6 |
Hernandez et al. [31] | 2000 | USA | Retrospective | 291 | 49.8 | IIb–IVa | Surgery or radiation | 400 | Yes | OS | 6 |
Qiu et al. [39] | 2010 | China | Retrospective | 318 | 43.0 | I–IV | NS | 400 | Not | OS | 6 |
Gadducci et al. [29] | 2010 | Italy | Retrospective | 46 | 47.0 | Ib–IIb | Surgery or chemotherapy | 272 | Not | OS, RFS | 6 |
Gadducci et al. [30] | 2010 | Italy | Retrospective | 140 | 47.0 | Ib–IIb | Surgery or chemotherapy | 272 | Not | OS, RFS | 6 |
Wang et al. [41] | 2012 | China | Retrospective | 111 | 42.0 | Ib–IIb | Surgery or chemotherapy | 266 | Not | OS, PFS | 5 |
Biedka et al. [27] | 2012 | Poland | Retrospective | 58 | NS | I–IV | Surgery or radiation | NS | Not | PFS | 5 |
Zhao et al. [44] | 2015 | China | Retrospective | 220 | NS | I–IIa | Surgery | 300 | Not | OS, RFS | 6 |
Xiao et al. [42] | 2015 | China | Retrospective | 238 | 52.0 | I–IV | Radiation and chemotherapy | 200 | Not | OS, PFS | 6 |
Li et al. [36] | 2015 | China | Retrospective | 380 | 51.0 | Ia–IIb | Surgery | 300 | Not | OS | 6 |
Koulis et al. [34] | 2017 | Canada | Retrospective | 257 | 50.0 | Ib–IV | Chemoradiotherapy and surgery | 400 | Yes (OS), No (PFS) | OS, PFS | 7 |
Kozasa et al. [35] | 2017 | Japan | Retrospective | 684 | NS | I–IV | Chemoradiotherapy and surgery | 350 | Yes | OS, PFS | 7 |
Zheng et al. [45] | 2017 | China | Retrospective | 800 | 49.5 | Ia–IIa | Surgery | 272 | Yes | OS, RFS | 7 |
Nakamura et al. [38] | 2018 | Japan | Retrospective | 98 | 65.0 | I–IV | Radiation and chemotherapy | 350 | Not | OS, PFS | 6 |
Xu et al. [43] | 2018 | China | Retrospective | 1189 | NS | Ia–IIa | Surgery | 300 | Yes | PFS | 7 |
Overall survival
Outcomes | Factors | Groups | HR and 95% CI | P value | Heterogeneity (%) | P value for heterogeneity | P value between subgroups |
---|---|---|---|---|---|---|---|
OS | Publication year | Before 2010 | 1.85 (1.43–2.40) | < 0.001 | 22.3 | 0.266 | 0.039 |
2010 or after | 1.29 (0.94–1.77) | 0.111 | 67.6 | 0.001 | |||
Country | Eastern | 1.15 (0.77–1.72) | 0.485 | 74.2 | <0.001 | 0.013 | |
Western | 1.78 (1.47–2.15) | <0.001 | 4.2 | 0.400 | |||
Sample size | ≥ 100 | 1.56 (1.28–1.89) | <0.001 | 44.6 | 0.036 | 0.029 | |
< 100 | 1.64 (0.31–8.64) | 0.562 | 85.0 | 0.001 | |||
Mean age (years) | ≥ 50.0 | 1.16 (0.63–2.13) | 0.638 | 83.7 | <0.001 | 0.055 | |
< 50.0 | 1.67 (1.34–2.08) | <0.001 | 17.1 | 0.295 | |||
Not reported | 1.68 (1.26–2.24) | <0.001 | 0.0 | 0.425 | |||
Treatment strategy | Surgery alone | 1.64 (1.05–2.57) | 0.031 | 66.0 | 0.012 | 0.774 | |
Other | 1.41 (1.06–1.89) | 0.020 | 65.9 | 0.002 | |||
Cutoff value | ≥ 300 | 1.53 (1.14–2.05) | 0.004 | 67.7 | <0.001 | 0.851 | |
< 300 | 1.43 (0.97–2.11) | 0.069 | 46.4 | 0.113 | |||
Adjusted | Yes | 1.68 (1.38–2.05) | <0.001 | 0.0 | 0.748 | 0.149 | |
No | 1.39 (0.98–1.96) | 0.063 | 70.7 | <0.001 | |||
Study quality | High | 1.67 (1.37–2.03) | <0.001 | 0.0 | 0.917 | 0.174 | |
Low | 1.44 (1.00–2.07) | 0.052 | 71.6 | <0.001 | |||
PFS | Publication year | Before 2010 | 1.54 (0.80–2.96) | 0.196 | – | – | 0.699 |
2010 or after | 1.29 (1.02–1.64) | 0.036 | 32.4 | 0.170 | |||
Country | Eastern | 1.18 (0.90–1.55) | 0.241 | 33.7 | 0.183 | 0.115 | |
Western | 1.71 (1.22–2.39) | 0.002 | 0.0 | 0.790 | |||
Sample size | ≥ 100 | 1.39 (1.16–1.67) | <0.001 | 0.0 | 0.442 | 0.235 | |
< 100 | 1.08 (0.22–5.24) | 0.919 | 69.2 | 0.071 | |||
Mean age (years) | ≥ 50.0 | 1.18 (0.72–1.94) | 0.508 | 63.8 | 0.063 | 0.215 | |
< 50.0 | 0.66 (0.27–1.62) | 0.365 | – | – | |||
Not reported | 1.48 (1.16–1.89) | 0.001 | 0.0 | 0.756 | |||
Treatment strategy | Surgery alone | 1.31 (0.93–1.84) | 0.127 | 0.0 | 0.797 | 0.794 | |
Other | 1.28 (0.92–1.78) | 0.144 | 49.9 | 0.076 | |||
Cutoff value | ≥ 300 | 1.42 (1.12–1.80) | 0.004 | 19.8 | 0.284 | 0.228 | |
< 300 | 1.02 (0.63–1.65) | 0.936 | 23.6 | 0.253 | |||
Not reported | 2.72 (0.61–12.10) | 0.189 | – | – | |||
Adjusted | Yes | 1.45 (1.11–1.88) | 0.006 | 0.0 | 0.547 | 0.539 | |
No | 1.23 (0.86–1.75) | 0.266 | 43.9 | 0.113 | |||
Study quality | High | 1.52 (1.24–1.88) | <0.001 | 0.0 | 0.789 | 0.046 | |
Low | 0.96 (0.57–1.60) | 0.867 | 37.8 | 0.185 | |||
RFS | Publication year | Before 2010 | 8.50 (0.78–92.40) | 0.079 | – | – | 0.173 |
2010 or after | 1.60 (1.22–2.10) | 0.001 | 0.7 | 0.388 | |||
Country | Eastern | 1.71 (1.24–2.34) | 0.001 | 0.0 | 0.587 | 0.624 | |
Western | 1.98 (0.75–5.24) | 0.167 | 53.9 | 0.114 | |||
Sample size | ≥ 100 | 1.55 (1.17–2.04) | 0.002 | 0.0 | 0.369 | 0.140 | |
< 100 | 3.35 (1.25–9.00) | 0.017 | 0.0 | 0.400 | |||
Mean age (years) | < 50.0 | 1.51 (1.04–2.18) | 0.029 | 17.7 | 0.297 | 0.308 | |
Not reported | 2.52 (0.82–7.71) | 0.105 | 29.0 | 0.235 | |||
Treatment strategy | Surgery alone | 1.75 (1.28–2.40) | <0.001 | 0.3 | 0.367 | 0.399 | |
Other | 1.54 (0.64–3.73) | 0.334 | 53.7 | 0.141 | |||
Cutoff value | ≥ 300 | 2.52 (0.82–7.71) | 0.105 | 29.0 | 0.235 | 0.308 | |
< 300 | 1.51 (1.04–2.18) | 0.029 | 17.7 | 0.297 | |||
Adjusted | Yes | 2.40 (0.59–9.69) | 0.221 | 45.3 | 0.176 | 0.872 | |
No | 1.63 (1.00–2.66) | 0.048 | 33.8 | 0.221 | |||
Study quality | High | 1.60 (1.09–2.36) | 0.017 | – | – | 0.886 | |
Low | 1.78 (1.04–3.05) | 0.034 | 38.2 | 0.183 |