Prognostic significance of multidrug-resistance protein (MDR-1) in renal clear cell carcinomas: A five year follow-up analysis

Table 3 Cox multivariate regression analysis: TNM tumour staging (stage I vs stages I, II, III, IV).

Co-variables	Significance (p)
Sex	0,613
Age*	0,715
Death from disease	0,004
Grading*	0,993
Tumour Size*	0,939
Multicentric Pattern of Growth	0,181
Thrombosis of caval vein	0,075
Necrosis	0,72
Adjuvant Therapy	0,783

We have considered tumour stage as state variable in correlation with different clinical and histopathological co-variables. The only significant statistical association has been observed between tumour stage and unfavourable outcome (p = 0.004).
*: for these co-variables, we have fixed the different cut-off values (≤ 65 years vs > 65 years for Age, G1 vs G2–G3–G4 for Grading, 7 cm vs > 7 cm as regards Tumour Size).