Risk Factors for Brain Metastases in Patients with Renal Cell Carcinoma

Table 3

Interaction test between age and tumor size on the risk of brain metastases from renal cell carcinoma.

Age (years)	Tumor size (cm)	Crude	Model I	Model II
<70	<7	Ref.	Ref.	Ref.
≥70	<7	1.593 (0.915, 2.775), 0.1000	1.369 (0.780, 2.402), 0.2740	1.459 (0.837, 2.545), 0.1828
<70	≥7 and <10	9.583 (6.540, 14.042), <0.0001	3.787 (2.499, 5.740), <0.0001	6.805 (4.574, 10.124), <0.001
≥70	≥7 and <10	6.221 (3.482, 11.114), <0.0001	2.569 (1.391, 4.742), 0.0026	4.363 (2.416, 7.879), <0.001
<70	≥10	14.990 (10.336, 21.740), <0.0001	3.072 (2.006, 4.705), <0.0001	8.555 (5.709, 12.821), <0.001
≥70	≥10	8.252 (4.320, 15.761), <0.0001	2.159 (1.081, 4.314), 0.0293	4.868 (2.503, 9.470), <0.001
interaction		0.0231	0.1679	0.0480

Model I was adjusted for bone metastasis, liver metastasis, and lung metastasis. Model II was adjusted for grade, N stage, marital status, race NEW, insurance, and Fuhrman grade.