Table 2. Univariate and multivariate analyses for overall survival (OS) and progression-free survival (PFS).

Clinical features	Univariate analysis		Multivariate analysis
	P for OS	P for PFS	HR (95% CI) for OS	P	HR (95% CI) for PFS	P
Age >60 years	0.038	0.159
Male gender	0.140	0.707
ECOG PS≥2	0.047	0.353
Elevated LDH	0.209	0.103
Deep brain lesion	0.696	0.361
Elevated CSF protein	0.074	0.064
Positive serum EBV	0.148	0.173
Non-CR1	0.791	0.005
Non-upfront ASCT	0.238	0.040
MSKCC scoring	0.029	0.046	2.56 (1.17-5.64)	0.019	1.56 (1.09-2.45)	0.041
IELSG scoring	0.036	0.487
PD-1 ≥70 cells/HPF	0.018	0.043	4.95 (1.54-15.86)	0.007	2.73 (1.12-6.69)	0.028
PD-L1 ≥100 cells/HPF	0.764	0.793
PD-L2 ≥100 cells/HPF	0.306	0.940

OS, overall survival; PFS, progression-free survival; HR, hazard ratio; CI, confidence interval; ECOG, Eastern Cooperative Oncology Group; PS, performance status; LDH, lactate dehydrogenase; CSF, cerebrospinal fluid; EBV, Epstein-Barr virus; CR1, complete response after first two cycles of chemotherapy; ASCT, autologous stem-cell transplantation; HPF, high power field; MSKCC, Memorial Sloan Kettering Cancer Center; IELSG, International Extranodal Lymphoma Study Group.