Clinically inapparent adrenal mass (Incidentaloma or Adrenaloma)

Abstract

Historically, the adrenal tumor that was discovered incidentally, usually during an imaging procedure (CT, MRI, ultrasound) for symptoms unrelated to adrenal disease (e.g., back pain), was called an incidentaloma [1]. As more physicians (and patients on their own) ordered these easily available imaging studies for common diseases potentially related to adrenal pathology (and not the known syndromes), such as mild and nonparoxysmal hypertension, diffuse obesity, and diabetes, an increasing number of unsuspected (but hardly incidental) adrenal tumors were found. I have proposed that these tumors be included with the true incidentalomas under the broader term "adrenaloma" because they share the same diagnostic and therapeutic dilemmas [2]. The term adrenaloma implies that the discovered tumor (incidentally or not) arises from the adrenal but is not obviously an aldosteronoma, a Cushing's syndrome adenoma, a pheochromocytoma, a virilizing or feminizing tumor, or a functioning adrenal carcinoma. Recently, at a State of the Science Conference at the National Institute of Health, the term "clinically inapparent adrenal mass" was coined [3]. The widespread teaching is that most adrenalomas are indolent tumors, nonfunctioning and asymptomatic, causing no harm to the patient [4,5].Recent studies,however,have shown that a high percentage of these tumors can be subclinically functioning, causing symptoms milder than those encountered in the well known adrenal hyperfunctioning syndromes but still harmful to the patient [6-14]. Thus, the screening tests of serum potassium, urinary VMA and serum cortisol do not suffice and more detailed and in depth laboratory investigation is necessary.The fear of adrenal carcinoma that dictated the approach to these tumors in the past (with the main emphasis on the size of the tumor) should be changed to the fear of the subtle function of these usually benign adrenal cortical adenomas with coexistent metabolic pathology (e.g., hypertension, obesity, diabetes).