Table 3. Independent prognostic factor by multivariate analysis for DSS in GSE41613.

Variable	Hazard ratio	95% CI	P value
Age (years)
≥60	Referent	0.340-1.708	0.510
<60	0.762
Gender
Male	Referent	0.564-2.915	0.553
Female	1.282
Treatment
Mono-modality*	Referent	0.279-0.2094	0.602
Multi-modality**	0.765
Clustering
PI-low	Referent	1.793-9.703	0.001
PI-high	4.171

*Surgery alone **Surgery with adjuvant treatment. DSS, disease specific survival; CI, confidential interval; PI, prognostic index.