Table 3. Associations of B7-H1 expression with death from RCC in 196 clear cell RCC specimens.

	Risk ratio (95% CI)*	P value
Tumor B7-H1 expression ≥10%
Univariate model	2.91 (1.39-6.13)	0.005
Adjusted for:
2002 primary tumor stage (T)	2.83 (1.34-5.96)	0.006
Regional lymph node involvement (N)	1.97 (0.87-4.45)	0.103
Distant metastases (M)	2.24 (1.06-4.73)	0.035
Primary tumor size	2.88 (1.37-6.06)	0.005
Nuclear grade	1.96 (0.90-4.30)	0.092
Histologic tumor necrosis	1.69 (0.78-3.65)	0.183
Lymphocyte B7-H1 expression ≥100
Univariate model	3.58 (1.74-7.37)	<0.001
Adjusted for:
2002 primary tumor stage (T)	3.34 (1.62-6.90)	0.001
Regional lymph node involvement (N)	3.59 (1.74-7.41)	<0.001
Distant metastases (M)	2.16 (1.03-4.53)	0.042
Primary tumor size	2.64 (1.27-5.46)	0.009
Nuclear grade	3.03 (1.46-6.29)	0.003
Histologic tumor necrosis	2.87 (1.39-5.95)	0.004
High-aggregate intratumoral B7-H1 expression
Univariate model	4.53 (1.94-10.56)	<0.001
Adjusted for:
2002 primary tumor stage (T)	4.07 (1.74-9.51)	0.001
Regional lymph node involvement (N)	3.36 (1.39-8.16)	0.007
Distant metastases (M)	3.12 (1.32-7.38)	0.009
Primary tumor size	4.25 (1.82-9.91)	<0.001
Nuclear grade	3.09 (1.28-7.50)	0.012
Histologic-tumor necrosis	2.68 (1.12-6.42)	0.027

^*Risk ratios represent the risk of death from clear cell RCC for the feature listed, either univariately or after multivariate adjustment. For example, patients with specimens that had ≥10% tumor B7-H1 expression were 2.9 times more likely to die from RCC compared with patients with specimens that had <10% tumor B7-H1 expression, even after adjusting for primary tumor size (P = 0.005).