Univariate and Multivariate Cox Regression with Respect to LRC
| Univariate | Multivariate | |||||||
| Parameter | Risk | HR | 95%CI | P | Bootstrap | HR | 95%CI | P |
| Clinical | ||||||||
| Age | <62 y | 3.4 | 1.17–9.88 | 0.025 | NA | 3.18 | 1.08–9.36 | 0.039 |
| T stage | >2 | 2.19 | 0.52–9.28 | 0.29 | NA | – | – | – |
| N stage | >0 | 2.07 | 0.49–8.76 | 0.32 | NA | – | – | – |
| TNM stage | >2 | 2.28 | 0.78–6.64 | 0.13 | NA | – | – | – |
| Histology | SCC | 1.25 | 0.57–2.74 | 0.57 | NA | – | – | – |
| Baseline PET | ||||||||
| MTV | >26.3 mL | 3.18 | 1.46–6.91 | 0.004 | 0.04 | 2.53 | 1.14–5.62 | 0.023 |
| TLG | >121 mL | 1.99 | 0.92–4.3 | 0.08 | 0.19 | – | – | – |
| SUV | >13.4 | 0.61 | 0.23–1.63 | 0.33 | – | – | – | – |
| SUR | >5.66 | 1.99 | 0.75–5.29 | 0.17 | – | – | – | – |
| Restaging PET | ||||||||
| rMTV | >6.6 mL | 3.59 | 1.58–8.14 | 0.002 | 0.024 | 3.64 | 1.59–8.34 | 0.002 |
| rTLG | >30.2 mL | 3.53 | 1.59–7.83 | 0.002 | 0.025 | 3.65 | 1.63–8.17 | 0.002 |
| rSUV | >5.33 | 2.81 | 1.22–6.48 | 0.015 | 0.069 | 2.65 | 1.15–6.11 | 0.023 |
| rSUR | >3.32 | 4.78 | 1.91–11.97 | <0.001 | 0.0082 | 4.75 | 1.9–11.9 | <0.001 |
| Fractional difference | ||||||||
| ∆MTV | >−35% | 2.16 | 1–4.69 | 0.051 | 0.16 | – | – | – |
| ∆TLG | >−79.9% | 2.58 | 1.04–6.43 | 0.042 | 0.12 | – | – | – |
| ∆SUV | >−38.8% | 1.59 | 0.73–3.47 | 0.24 | – | – | – | – |
| ∆SUR | >−48% | 2.18 | 0.97–4.9 | 0.059 | 0.16 | – | – | – |
CI = confidence interval; NA = not applicable; SCC = squamous cell carcinoma.
In multivariate analyses, each PET parameter was analyzed separately together with age, the only significant clinical parameter in the univariate Cox regression. HRs and P values of clinical parameters were averaged over all analyses. Bootstrap column shows sample-averaged P value resulting from corresponding bootstrap analysis. Only PET parameters with P < 0.1 were included in multivariate analysis.