Table 4 The association between clinical characteristics and earlier recurrence for NPC patients by ordered logistic regression

Age (years, < 50 vs. ≥ 50)

0.949 (0.742–1.215)

0.680

Gender (female vs. male)

0.591 (0.434–0.805)

< 0.001

0.607 (0.444–0.831)

0.002

T stage

T0-1

1.000 (Reference)

1.000 (Reference)

T2

0.948 (0.597–1.507)

0.822

0.868 (0.541–1.390)

0.555

T3

1.314 (0.907–1.903)

0.148

1.205 (0.805–1.805)

0.364

T4

1.868 (1.273–2.742)

0.001

1.552 (1.019–2.365)

0.041

N stage

N0

1.000 (Reference)

1.000 (Reference)

N1

2.128 (1.094–4.139)

0.026

1.744 (0.885–3.438)

0.108

N2

2.629 (1.352–5.110)

0.004

1.951 (0.975-3.900)

0.059

N3

2.435 (1.217–4.872)

0.012

1.719 (0.822–3.596)

0.150

EBV DNA_{pre−treatment}

(copies/mL, > 4000 vs. ≤ 4000)

1.298 (1.014–1.662)

0.038

0.956 (0.731–1.250)

0.742

EBV DNA_pre−RT

(detectable vs. undetectable)

1.986 (1.532–2.574)

< 0.001

1.786 (1.349–2.365)

< 0.001

EBV DNA_post−RT

(detectable vs. undetectable)

1.927 (1.438–2.583)

< 0.001

1.460 (1.063–2.006)

0.020

Induction chemotherapy (no vs. yes)

2.061 (1.328-3.200)

0.001

1.712 (1.023–2.868)

0.041

Concurrent chemotherapy (no vs. yes)

1.139 (0.867–1.496)

0.351

Adjuvant chemotherapy (no vs. yes)

1.438 (0.984–2.099)

0.060

Residue (no vs. yes)

1.951 (1.489–2.556)

< 0.001

1.739 (1.315-2.300)

< 0.001