Table II.

Risk factors for overall survival (OS).

	Univariate analysis			Multivariate analysis
Variables	HR	95% CI	P-value	HR	95% CI	P-value
Age >60 years	1.07	0.67–1.72	0.771
Male gender	0.76	0.52–1.11	0.153
ECOG score ≥2	2.77	1.99–3.86	<0.001	3.49	2.20–5.54	<0.001
Stages III/IV	1.76	1.15–2.70	0.010
Extranodal involvement >1	0.93	0.65–1.31	0.666	0.51	0.31–0.85	0.001
Positive B symptomsa	2.12	1.55–2.91	<0.001	1.67	1.12–2.50	0.012
Bone marrow involvement	0.53	0.40–0.71	<0.001	0.39	0.26–0.61	<0.001
LDH level >ULN	2.00	1.49–2.68	<0.001	2.07	1.40–3.06	<0.001
β2-MG level >ULN	2.19	1.60–3.00	<0.001
IPI >2	2.08	1.48–2.92	<0.001

^aB symptoms: fever, night sweats or weight loss.

ECOG, Eastern Cooperative Oncology Group; LDH lactate dehydrogenase; β2-MG, β2-microglobulin; IPI, International Prognostic Index; ULN, upper limit of normal; HR, hazard ratio; CI, confidence interval.