Table 2.
Univariate cox regression analysis for overall survival, adjusted for ctDNA status, age, gender, WHO performance score, HER-2 status, and stage at baseline, and ctDNA status, stage and tumor regression grade after surgery
| Variable | OS, baseline, n = 79 | OS, after surgery, n = 53 | ||
|---|---|---|---|---|
| HR (95% CI) | p value | HR (95% CI) | p value | |
| ctDNA | ||||
| Not detected (negative) | Reference | Reference | ||
| Detected (positive) | 1.09 (0.55–2.19) | 0.80 | 6.63 (2.18–20.21) | < 0.001 |
| Age (groups) | ||||
| < 65 | Reference | – | ||
| ≥ 65 | 1.19 (0.57–2.49) | 0.62 | – | – |
| Gender | ||||
| Female | Reference | – | ||
| Male | 1.12 (0.43–2.93) | 0.81 | – | – |
| PS at baseline | ||||
| 0 | Reference | – | ||
| 1–2 | 1.35 (0.65–2.76) | 0.41 | – | – |
| HER-2 status at baseline | ||||
| Normal | Reference | – | ||
| Positive | 0.85 (0.42–1.93) | 0.79 | – | – |
| Clinical tumor stage | ||||
| cT1/T2 | Reference | – | ||
| cT3/T4 | 0.95 (0.44–2.11) | 0.91 | – | – |
| Clinical nodal stage | ||||
| cN0 | Reference | – | ||
| cN + | 2.12 (1.02–4.39) | 0.05 | – | – |
| Pathological tumor stage | ||||
| ypT1/T2 | – | Reference | ||
| ypT3/T4 | – | – | 13.8 (1.83–104.14) | < 0.001 |
| Pathological nodal stage | ||||
| ypN0 | – | Reference | ||
| ypN + | – | – | 3.11 (1.07–8.99) | 0.027 |
| TRG | ||||
| TRG1-2 | – | Reference | ||
| TRG3-5 | – | – | 2.01 (0.65–6.20) | 0.20 |
p values in bold indicate statistical significance (p ≤ 0.05)
OS overall survival; HR hazard ratio; ctDNA circulating tumor DNA; PS WHO performance score; HER-2 human epidermal growth factor receptor 2; TRG tumor regression grade according to Mandard