Summary of the structure and concentration of the eight statistically validated volatile organic compounds (VOCs) of 130 VOC originally obtained from the exhaled breath samples in various study groups, and the binary comparisons between the tested groups showing significant p values (<0.017)
| 2-Propenenitrile | Furfural | 2-Butoxy-ethanol | Hexadecane | 4-Methyl octane | 1,2,3-Tri-methyl-benzene | α-methyl-styrene | 2-Butanone | |
|---|---|---|---|---|---|---|---|---|
| Concentration (ppb) | ||||||||
| Retention time (min) | 3.0 | 16.9 | 21.1 | 28.8 | 18.7 | 25.7 | 25.1 | 4.04 |
| m/z* | 53 | 39 | 57 | 57 | 43 | 105 | 118 | 43 |
| LOD (ppb) | 1.3 | 1.4 | 8.5 | 2.3 | 0.2 | 2.7 | 2.5 | 2.9 |
| LOQ (ppb) | 1.8 | 1.5 | 8.75 | 6.9 | 0.5 | 8.2 | 7.6 | 8.7 |
| GC | 13.2±13.7 | 5.6±3.5 | 26.1±4.3 | 10.7±12.3 | 18.8±4.5 | 20.0±13.6 | 28.5±4.3 | 68.3±49.0 |
| OLGIM 0–IV | 7.5±6.2 | 4.5±0.9 | 24.9±1.3 | 4.2±4.1 | 18.0±3.3 | 11.9±7.9 | 26.2±1.8 | 90.4±85.4 |
| PUD | 12.5±14.9 | 5.2±2.4 | 25.0±2.1 | 7.2±9.9 | 19.7±8.4 | 18.3±16.7 | 27.6±6.0 | 77.7±69.1 |
| Non-advanced (stages I–II) GC | 16.7±15.1 | 5.3±1.2 | 26.3±1.6 | 12.3±11.3 | 18.1±2.8 | 23.2±14.1 | 29.3±4.3 | 82.4±57.2 |
| Advanced (stages III–IV) GC | 14.6±13.9 | 5.5±2.9 | 25.6±1.4 | 10.6±11.7 | 18.9±4.2 | 21.4±14.0 | 28.8±4.7 | 61.9±43.1 |
| OLGIM 0–II | 7.5±6.2 | 4.5±1.0 | 24.9±1.20 | 4.2±4.0 | 18.0±3.4 | 11.6±7.7 | 26.1±1.5 | 90.3±83.3 |
| OLGIM 0 | 7.9±7.9 | 4.4±0.8 | 24.9±1.2 | 4.4±4.0 | 18.2±3.5 | 4.9±3.3 | 26.1±1.5 | 91.1±83.8 |
| OLGIM I–II | 7.1±2.6 | 4.6±1.1 | 24.9±1.2 | 3.8±4.0 | 17.7±3.1 | 3.9±2.6 | 26.1±1.5 | 91.2±84.0 |
| OLGIM III–IV | 6.1±1.1 | 4.5±1.0 | 25.2±1.3 | 3.0±2.1 | 17.1±2.6 | 12.0±7.8 | 26.7±3.1 | 89.5±83.0 |
| p Value for group comparisons (t test) | ||||||||
| GC vs OLGIM 0–IV | <0.0001 (GC) | 0.0001 (GC) | 0.0002 (GC) | <0.0001 (GC) | – | – | – | – |
| GC vs OLGIM 0 | 0.001 (GC) | – | – | 0.0001 (GC) | – | – | <0.0001 (GC) | – |
| GC vs OLGIM 0–II | – | – | 0.019 (GC) | <0.0001 (GC) | – | – | <0.0001 (GC) | 0.009 (GC) |
| GC vs OLGIM I–II | – | – | – | <0.0001 (GC) | – | – | – | – |
| GC vs OLGIM III–IV | – | – | – | <0.0001 (GC) | – | – | – | – |
| GC vs OLGIM I–IV | 0.0001 (GC) | – | – | 0.0004 (GC) | – | 0.0002 (GC) | <0.0001 (GC) | – |
| GC vs PUD | – | – | – | – | – | – | – | – |
| OLGIM 0–IV vs PUD | – | 0.006 (PUD) | – | <0.0001 (PUD) | 0.017 (PUD) | – | – | – |
*m/z-mass/charge ratio of the mass spectrometry signal.
GC, gastric cancer; GCMS, gas chromatography linked to mass spectrometry; LOD, limit of detection of the GCMS; LOQ, limit of quantification of the GCMS; OLGIM, operative link on gastric intestinal metaplasia; PUD, peptic ulcer disease.