Table 1.
Design and characteristics of studies included in the meta-analysis
| Study, year | Coutry | Study design | No. of patients | Age, years | Chemotherapy regime | Clinical stage | Follow-up, months | NOS | |
|---|---|---|---|---|---|---|---|---|---|
| ACT | No-ACT | ||||||||
| Bliggenstorfer (2022) | USA | Retrospective | 494 | 1054 | Mean: 60.21 | NA | II = 4524 III = 3418 | NA | 7 |
| Capirci (2008) | Italy | Retrospective | 127 | 439 | Mean: 61.8 | 5-FU, capecitabine, raltitrexed, 5-FU + Mitomycin C, 5-FU + cisplatin, oxaliplatin + 5-FU, oxaliplatin + raltitrexed, oxaliplatin + capecitabine | II = 250 III = 254 | 45.6 moths | 6 |
| Chen (2023) | China | Retrospective | 207 | 73 | Median: 53.1 | FOLFOX mFOLFOX6 | II = 88 III = 192 | 55 months | 8 |
| Dossa (2018) | USA | Retrospective | 667 | 667 | Median: 56.5 | NA | NA | 36.9 months | 8 |
| Fukui (2022) | Japan | Retrospective | 75 | 30 | NA | 5-FU, FL, FOLFOX | NA | 49 months | 9 |
| Gahagan (2020) | USA | Retrospective | 1513 | 4319 | Mean: 59.83 | NA | NA | NA | 7 |
| Gamaleldin (2017) | USA | Retrospective | 47 | 83 | Mean: 58.9 | 5-FU, FL | II = 73 III = 56 | 68.4 months | 9 |
| Gave (2014) | Israel | Retrospective | 35 | 17 | Median: 65.7 | 5-FU, capecitabine | NA | 49.4 months | 7 |
| Govindarajan (2011) | USA | Retrospective | 64 | 9 | NA | 5-FU-based, FL, FOLFOX | NA | 69.6 months | 9 |
| He (2020) | China | Retrospective | 712 | 297 | Median: 55 | Ora/i.v. fluoropyrimidine, capecitabine, FL, CapeOX, FOLFOX, FOLFOXIRI, FOLFIRI | II = 229 III = 780 | 35 months | 9 |
| Hu (2019) | China | Retrospective | 56 | 115 | Mean: 56.5 | Capecitabine, CapeOX | II = 55 III = 116 | 120 months | 7 |
| Jiang (2021) | China | Retrospective | 187 | 60 | NA | Capecitabine, CapeOX | II = 67 III = 180 | 53 months | 8 |
| Kim (2017) | Korea | Retrospective | 50 | 40 | NA | FL, capecitabine | NA | 70.7 months | 7 |
| Kiran (2012) | USA | Retrospective | 14 | 34 | NA | 5-FU, FL | NA | 52.6 months | 6 |
| Kuan (2016) | China | Retrospective | 114 | 115 | Mean: 59.59 | FL, tegafur, capecitabine | II = 87 III = 172 | 37 months | 7 |
| Kuo (2022) | China | Retrospective | 115 | 155 | NA | 5-FU, capecitabine, oxaliplatin, leucovorin, UFUR FL, capecitabine, FOLFOX, CapeOX, 5-FU + oxaliplatin | NA | 50.88 months | 7 |
| Lai (2023) | USA | Retrospective | 780 | 1441 | Median: 60.59 | NA | II = 1083 III = 1138 | 50.9 months | 8 |
| Lee (2015) | Korea | Retrospective | 32 | 12 | NA | Capecitabine, uracil-tegafur, doxifluridine, capecitabine | NA | 60.5 months | 9 |
| Lichthardt (2017) | Germany | Retrospective | 9 | 15 | NA | 5-FU, capecitabine, FOLFOX, FOLFIRI | NA | NA | 5 |
| Lorenzon, 2017 | Italy | Retrospective | 77 | 155 | NA | Oral/i.v. fluoropyrimidine | NA | 47.6 months | 7 |
| Lu (2018) | China | Retrospective | 22 | 29 | NA | CapeOX, capecitabine, FOLFOX, oxaliplatin + S-1 | NA | 50 months | 7 |
| Mass (2015) | Netherlands | Retrospective | 290 | 608 | Mean: 61 | FL, FOLFOX, 5-FU,capecitabine, CapeOX | NA | NA | 7 |
| Morris (2021) | USA | Retrospective | 778 | 1643 | Median: 60.64 | NA | II = 1233 III = 1188 | 42.3 months | 8 |
| Nafouje (2022) | USA | Retrospective | 1292 | 1292 | Mean: 57.2 | NA | II = 1123 III = 1461 | 56.4 months | 7 |
| Nguyen (2019) | USA | Retrospective | 60 | 36 | Mean: 58.14 | 5-FU, capecitabine, FULFOX | II = 25 III = 71 | 77.76 months | 8 |
| Peng (2018) | China | Retrospective | 83 | 22 | Mean: 52.9 | CapeOX | II = 35 III = 70 | 49 months | 5 |
| Polanco (2018) | USA | Retrospective | 741 | 741 | NA | NA | II = 698 III = 784 | 39 months | 7 |
| Shahab (2017) | USA | Retrospective | 789 | 2102 | Mean: 60.1 | NA | II = 1612 III = 1279 | NA | 7 |
| Tay (2016) | Australia | Retrospective | 97 | 29 | NA | Oral/i.v. fluoropyrimidine, capecitabine, FOLFOX, FL | NA | 45.5 months | 8 |
| Turner (2018) | USA | Retrospective | 1379 | 2726 | Mean: 57.7 | NA | II = 2183 III = 1922 | NA | 7 |
| Voss (2020) | USA | Retrospective | 139 | 54 | NA | 5-FU, capecitabine, FOLFOX, CapeOX, oxaliplatin | NA | 63 months | 7 |
| Xu (2016) | USA | Retrospective | 484 | 1243 | NA | NA | NA | NA | 8 |
| Yeo (2010) | Korea | Retrospective | 256 | 48 | NA | 5-FU, FL, FOLFOX, FOLFIRI, capecitabine, oral/i.v. fluoropyrimidine | NA | 43 months | 7 |
| Zhou (2016) | China | Retrospective | 19 | 21 | Mean: 54.05 | CapeOX, FOLFOX4, capecitabine | II = 13 III = 22 | 57 months | 7 |
USA United States of America, ACT Adjuvant chemotherapy, No number of patients, NA not available, FOLFOX folinic acid + fuorouracil + oxaliplatin, FU fuorouracil, FL fuorouracil + leucovorin, CapeOX capecitabine + oxaliplatin, FOLFIRI folinic acid + fuorouracil + irinotecan, NOS Newcastle–Ottawa Scale