Table III.

Univariate and multivariate analyses of prognostic factors in the 1,501 nasopharyngeal carcinoma patients.

		Univariate	Multivariatea
Treatment outcome	Variable	P-value	HR	95% CI	P-value
CCRT patients (n=412)
Overall survival	Age (>45 vs. ≤45 years)	0.033	1.576	1.096–2.264	0.014
	N status (N2–3 vs. N0–1)	0.079	1.508	1.055–2.154	0.024
	PLT count
	Low vs. moderate	0.026	2.024	1.165–3.516	0.012
	High vs. moderate	0.022	1.742	1.090–2.786	0.020
	High vs. low	0.857	0.861	0.445–1.665	0.656
Local-regional recurrence-free survival	Age (>45 vs. ≤45 years)	0.057	1.550	0.983–2.444	0.059
Distant metastasis-free survival	T status (T3–4 vs. T1–2)	0.069	1.616	0.912–2.863	0.100
	N status (N2–3 vs. N0–1)	0.092	1.627	0.933–2.835	0.086
	PLT count
	Low vs. moderate	0.286	1.720	0.670–4.412	0.259
	High vs. moderate	0.012	2.110	1.084–4.108	0.028
	High vs. low	0.535	1.227	0.429–3.512	0.815
RT patients (n=1089)
Overall survival	Age (>45 vs. ≤45 years)	0.001	1.667	1.286–2.161	<0.001
	Gender (female vs. male)	0.046	1.397	1.013–1.925	0.041
	N status (N2–3 vs. N0–1)	0.003	1.618	1.227–2.135	0.001
	PLT count
	Low vs. moderate	0.149	1.265	0.860–1.860	0.233
	High vs. moderate	0.038	1.740	1.283–2.362	<0.001
	High vs. low PLT	0.822	1.376	0.886–2.137	0.155
Local-regional recurrence-free survival	Age (>45 vs. ≤45 years)	0.003	1.602	1.181–2.173	0.002
	N status (N2–3 vs. N0–1)	0.061	1.422	1.014–1.994	0.041
Distant metastasis-free survival	Age (>45 vs. ≤45 years)	0.083	1.553	0.998–2.416	0.051
	N status (N2–3 vs. N0–1)	0.035	1.653	1.032–2.648	0.037
	PLT count
	Low vs. moderate	0.666	1.148	0.541–2.437	0.718
	High vs. moderate	<0.001	2.819	1.766–4.497	<0.001
	High vs. low PLT	0.025	2.454	1.121–5.372	0.025

^aThe following parameters were included in the multivariate analysis using Cox proportional hazards model by backward elimination: Age (>45 vs. ≤45 years); gender (female vs. male); T status (T3–4 vs. T1–2); N status (N2–3 vs. N0–1); PLT count (low vs. moderate; high vs. moderate; high vs. low). Variables with P-values >0.10 were excluded from the model.

HR, hazard ratio; CI, confidence interval; CCRT, concurrent chemoradiotherapy; N, node; PLT, platelet; T, tumor; RT, radiotherapy alone.