Distinction between adrenal adenomas and metastases using MR imaging

Area of Science:

• Radiology
• Oncology
• Endocrinology

Background:

• Adrenal masses are common findings in patients with known cancer.
• Distinguishing adrenal metastases from benign adenomas is crucial for treatment planning.
• Computed tomography (CT) often detects adrenal masses but cannot reliably differentiate their nature.

Purpose of the Study:

• To evaluate the utility of magnetic resonance imaging (MRI) in differentiating adrenal metastases from nonfunctioning adenomas.
• To assess the signal intensity characteristics on T2-weighted MRI for distinguishing these adrenal lesions.

Main Methods:

• Retrospective analysis of 12 patients with known neoplastic disease and adrenal masses detected by CT.
• MRI including T2-weighted spin echo sequences (SE 2,500/80) was performed.
• Signal intensity of adrenal masses was compared between metastatic and adenoma groups.

Main Results:

• Three patients with confirmed adrenal metastases exhibited high signal intensity on T2-weighted MRI.
• Nine patients with nonfunctioning adrenal adenomas demonstrated low signal intensity on T2-weighted MRI.
• MRI signal intensity on T2-weighted images effectively differentiated metastases from adenomas.

Conclusions:

• T2-weighted MRI is a valuable tool for distinguishing adrenal metastases from nonfunctioning adenomas.
• This imaging technique can aid in the pre-operative evaluation of patients with incidental adrenal masses and known malignancy.
• Accurate characterization of adrenal masses impacts clinical management and surgical decisions.