ACC can be functional and nonfunctional; functional ACC may produce only hormonal precursor excess, because they may not be able to complete the steroidogenesis process. Elevated levels of hormones associated with clinical symptoms have clinical relevance. Excess of mineral corticosteroids is not usually encountered; on the other hand, excesses of the corticosteroids androgen and estrogen are frequently responsible for clinical symptoms.

When patients have no clinical symptoms, before the classification of an ACC as nonfunctioning, they should be screened for steroid precursors (especially dehydroepiandrosterone sulfate (DHEAS), through serum and urine assays) to avoid an incorrect diagnosis [13]. Clinically, symptomatic ACCs can lead to symptoms because of an abdominal mass or a hormonal excess, such as Cushing’s syndrome, virilization, feminization, or Conn’s syndrome. A complete diagnosis for ACC must evaluate the clinical history, physical examination, laboratory tests, and radiological examinations.

The preoperative laboratory workup for suspected ACC comprises assessment of basal cortisol, adrenocorticotropic hormone (ACTH), DHEAS, 17-hydroxyprogesterone, androstenedione, testosterone, and estradiol levels as well as a dexamethasone suppression test and measurement of urinary free cortisol excretion. The ratio of aldosterone to renin is measured in patients with hypertension or hypokalemia.

Radiological imaging is used in making the diagnosis and in staging the tumor. Computed tomography (CT), ultrasound, and magnetic resonance imaging (MRI) are the most common examinations used for both diagnosis and staging. The chest and abdomen are examined first because the lung and liver are the most common site of metastases from ACC. Metastases can be detected with these methods when the diameter is >1 cm.

The detection of liver metastases using multislice spiral computed tomography (MSCT) can be difficult because of the hypervascularization of the metastases. The arterial filling phase of hypervascularized hepatic metastases of ACC occurs within a few seconds, as demonstrated by echo-enhanced ultrasound. Because liver contrast-enhanced CT is performed 60 s after intravenous injection of a contrast agent, the hypervascularization of the ACC metastases does not allow good visualization of the enhancement phase. Lesions <1 cm cannot be diagnosed in the portal phase if the wash out of the contrast agent is not complete. One solution to this problem might be the use of multiphase MSCT with a shorter acquisition interval that might be able to detect small lesions. However, this procedure carries risks because of high radiation exposure of the metastases. The arterial filling phase of hypervascularized hepatic metastases of ACC occurs within a few seconds, as demonstrated by echo-enhanced ultrasound. Because liver contrast-enhanced CT is performed 60 s after intravenous injection of a contrast agent, the hypervascularization of the ACC metastases does not allow good visualization of the enhancement phase. Lesions <1 cm cannot be diagnosed in the portal phase if the wash out of the contrast agent is not complete. One solution to this problem might be the use of multiphase MSCT with a shorter acquisition interval that might be able to detect small lesions. However, this procedure carries risks because of high radiation exposure [14].

Ultrasound, in both the conventional and echo-enhanced modes, is a sensitive and useful method especially in follow-up examinations. At this stage, when the primary tumor has been removed, the use of ultrasound can permit the diagnosis of small lesions earlier than other methods. This is particularly useful when a single lesion located in the liver can be diagnosed; however, when multiple metastases exist, merely detecting a few additional lesions may not affect overall management [14].

The use of MRI to detect liver metastases of ACC has not been used extensively to date because of lack of capacity, high costs, and the rarity of liver metastases in this disease. To differentiate benign and malignant adrenal tumors, [¹⁸F]fluorodeoxyglucose (FDG)–position emission tomography (PET) and PET/CT imaging have been used, but the results have not been useful and no clear indication for these techniques in liver metastases has yet been identified [15].

¹¹C-Metomidate (MTO)-PET is a new adrenal imaging technique that has been used to differentiate tumors of cortical origin from those of noncortical origin. Metomidate tracers specifically bind to adrenocortical CYP11B enzymes, which catalyze the final steps of steroid synthesis. Additional evaluation is needed and application to liver metastases has not been reported [16].

The diagnostic accuracy of fine-needle biopsy is low [17] and violation of the tumor capsule may promote needle track metastases. Fine-needle biopsy can be used to establish a diagnosis, but only after the failure of other diagnostic methods.

ACC is a rare disease with a poor prognosis. Conclusions in the literature are varied, but all reports agree that surgical resection, when possible, represents the only effective treatment for the primary tumor and for isolated metastases [1, 11, 12]. Effective management of liver metastases from ACC, in selected patients, is associated with long-term survival, but the outcome depends on patient selection and on the primary tumor [18].