Table II.
Characteristics of studies.
| Sample size | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Study | Country | Patients with CRC | Healthy controls | Polyps adenoma | Sample extraction | Analytical platform | Data analysis | Total metabolites detected | No. of metabolites significantly different | (Refs.) |
| Qiu et al, 2009 | China | 64 | 65 | – | Yes | GC-TOF-MS | MATLAB 7.0 | 22 | 21 | (19) |
| UPLC-TOF-MS | MarkerLynx 4.1 | 16 | 13 | |||||||
| Nishiumi et al, 2012 | Japan | 60 | 60 | – | Yes | GC-MS | MetAlign | 126 | 54 | (20) |
| Tan et al, 2013 | China | 101 | 102 | – | Yes | GC-TOF-MS | ChromaTOF | 107 | 34 | (21) |
| UPLC-TOF-MS | MarkerLynx 4.1 | 147 | 44 | |||||||
| Cross et al, 2014 | USA | 254 | 254 | – | Yes | UPLC-GC-MS | SAS 9.1.3 and R language 3.0.1 | 278 | 21 | (22) |
| Zamani et al, 2014 | Iran | 33 | 33 | – | No | NMR | Chenomix 6.4 | 14 | 14 | (23) |
| Deng et al, 2016 | USA | 28 | 55 | 44 | No | NMR | Bruker TopSpin 3.5 | 70 | 5 | (24) |
| Uchiyama et al, 2017 | Japan | 56 | 60 | 59 | Yes | CE-TOF-MS | PeakStat | 139 | 70 | (25) |
| Long et al, 2017 | USA | 30, 50 | 30, 50 | 30, 50 | Unknown | LC-MS | Stata version 10.1- | 404 | 50 | (26) |
| Nishiumi et al, 2017 | Japan | 282 | 291 | – | Yes | GC-QqQ-MS | JMP12 | 64 | 41 | (27) |
CRC, colorectal cancer; GC, gas chromatography; MS, mass spectrometry; TOF-MS, time-of-flight MS; UPLC, ultra-performance liquid chromatography; NMR, nuclear magnetic resonance; CE, capillary electrophoresis; LC, liquid chromatography; QqQ, triple-quadrupole.