Can dynamic gadolinium-enhanced magnetic resonance imaging with chemical shift studies predict the status of adrenal masses?

Endoscopic adrenalectomy represents the new gold standard in the surgical treatment of benign adrenal lesions up to 6 cm. In some cases lesions larger than 10 cm have been removed laparoscopically to offer the patient the advantages of the minimally invasive technique. The larger the diameter of an adrenal lesion, the greater the probability of malignancy. In a prospective study 130 consecutive patients (88 women, 42 men; mean age 47.8 years) with 137 adrenal lesions earmarked for surgery underwent preoperative gadolinium-enhanced magnetic resonance imaging (MRI) with chemical shift studies (CSS). The aim of this study was to predict the status (benign, borderline, malignant) of adrenal lesions by MRI irrespective of tumor size. There were 14 patients with malignant tumors, 3 had borderline tumors (epithelial tumors with high malignant potential), and the remaining 120 had benign adrenal lesions. Five malignant lesions (36%) had a diameter < 6 cm. MRI correctly predicted 11 of 14 malignant tumors (1 malignant pheochromocytoma and 2 adrenocortical carcinomas had false-negative results), 117 of 120 benign lesions, and 2 of 3 borderline lesions. All but two malignant tumors were operated on using open surgery; 82 (68%) of 120 benign adrenal lesions were treated using the transperitoneal laparoscopic approach. Tumor size alone is not suitable for predicting the status of adrenal lesions. Dynamic gadolinium-enhanced MRI with CSS can predict the status of at least 95% of adrenal lesions. Tumors> 6 cm classified as benign by preoperative MRI may be removed laparoscopically by endocrine surgeons experienced in endoscopic adrenalectomy.