Table 3 Studies included in the review
| Â | Low CEA | High CEA | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
NO | Author | Year of publication | No. of patients | CEA cut-off | No. of LN | 5 year survival | Recurrence | No. of LN | 5 year survival | Recurrence |
1 | Ryo Maeda [29] | 2017 | 378 | 5 ng/mL | 263 N0, 15 N1–3 | 87.70% |  | 81 N0, 19 N1–3 | 75.50% |  |
2 | Yusuke Takahashi [30] | 2015 | 171 | 5 ng/mL |  |  |  |  |  |  |
3 | Gianfranco Buccheri [18] | 2003 | 118 | 10 ng/mL |  |  | 16% |  |  | 70% |
4 | Riken Kawachi [31] | 2009 | 815 | 5 ng/mL |  | 76.70% |  |  | 56.60% |  |
5 | Niels Reinmuth [19] | 2002 | 67 | 5 ng/mL |  |  |  |  |  |  |
6 | Sukki Cho [32] | 2013 | 770 | 3.5 ng/mL (mean) |  |  |  |  |  |  |
7 | Kaoru Kaseda [33] | 2016 | 246 | 5 ng/mL | 168 N0, 19 N1-N2 |  |  | 47 N0, 12 N1-N2 |  |  |
8 | Tatsuya Kato [34] | 2013 | 177 | 3 ng/mL |  | 93.2% (ADC), 81% (SCC) | 6.80% |  | 59.4% (ADC), 51.9% (SCC) | 38.80% |
9 | Terumoto Koike [35] | 2012 | 894 | 5 ng/mL |  |  |  |  |  |  |
10 | Hiroaki Komatsu [36] | 2013 | 279 | 2.8 ng/mL | 87 N0, 1 skip N2 |  |  | 143 N0, 11 skip N2 |  |  |
11 | Yasuhiro Tsutani [37] | 2014 | 100 | 2.5 ng/mL |  |  |  |  |  |  |
12 | Bo Ye [38] | 2014 | 651 | 5 ng/mL | 371 N0, 11 N1, 8 N2 |  |  | 211 N0, 32 N1,18 N2 |  |  |