Table 5.

Multivariate Analysis—Predictors of a Malignant Adrenal Mass^a

Any malignant mass
Variable	All patientsb (n=547)		Only for patients with unenhanced HU measurements availableb (n=297)
	Odds ratio (95% CI)	P value	Odds ratio (95% CI)	P value
Sex (male vs female)	1.57 (1.04-2.37)	.03c	1.45 (0.72-2.95)	.29
Age at diagnosis (each decade increase)	1.2 (1.04-1.37)	.01c	1.08 (0.86-1.4)	.49
Mode of discovery (nonincidental vs incidental)	6.99 (4.5-10.99)	<.001c	5.92 (2.7-13.4)	<.001c
Adrenal mass size (each 1-cm increase)	1.2 (1.14-1.3)	<.001c	1.3 (1.17-1.48)	<.001c
Unenhanced CT attenuation (each 1-HU increase)			1.08 (1.06-1.1)	<.001c

Other malignancy
Variable	All patientsb (n=547)		Only for patients with available work-up for adrenal glucocorticoid productionb (n=393)
	Odds ratio (95% CI)	P value	Odds ratio (95% CI)	P value
Sex (male vs female)	2.4 (1.5-3.9)	.002c	1.8 (0.95-3.4)	.07
Age at diagnosis (each decade increase)	1.45 (1.2-1.7)	<.001c	1.6 (1.3-2.1)	<.001c
Mode of discovery (nonincidental vs incidental)	7.8 (4.7-13)	<.001c	5.5 (2.8-11)	<.001c
Adrenal mass size (each 1-cm increase)	1.1 (0.98-1.15)	.17	0.9 (0.8-1)	.05c
Hypercortisolism (vs normal cortisol production)			0.2 (0.1-0.4)	<.001c

ACC
Variable	All patientsb (n=547)		Only for patients with available work-up for adrenal glucocorticoid productionb (n=393)
	Odds ratio (95% CI)	P value	Odds ratio (95% CI)	P value
Sex (male vs female)	0.53 (0.29-0.95)	.03c	0.79 (0.37-1.6)	.52
Age at diagnosis (each decade increase)	0.83 (0.69-0.99)	.04c	0.83 (0.67-1.02)	.08c
Mode of discovery (nonincidental vs incidental)	2.48 (1.4-4.4)	.002c	2.9 (1.4-5.9)	.003c
Adrenal mass size (each 1-cm increase)	1.36 (1.27-1.47)	<.001c	1.5 (1.37-1.68)	<.001c
Hypercortisolism (vs normal cortisol production)			3.5 (1.7-7.6)	<.001c

^aCT = computed tomography; HU = Hounsfield units.

^bPheochromocytomas were excluded from this analysis.

^cIndicates statistical significance with P values <.05.