The likelihood of malignancy, the presence and degree of hormone overproduction, and the age, health and preference of the patient should determine the appropriate response to adrenal incidentalomas discovered through imaging, according to a clinical practice guideline released by the European Society of Endocrinology.
The interdisciplinary guideline group, consisting of 10 international experts, developed the recommendations in part to address a rise in the number of imaging procedures available, leading to an increase in the detection of asymptomatic adrenal masses discovered during imaging for other reasons. In most cases, adrenal incidentalomas are nonfunctioning adrenocortical adenomas, but they may also present conditions requiring therapeutic intervention, according to the guideline.
“These guidelines are an important step in the handling of adrenal incidentaloma,” Martin Fassnacht, MD, of the division of endocrinology and diabetes at University Hospital, University of Würzburg, Germany, said in a press release. “We provide, for the first time, evidence-based recommendations to avoid over-diagnostics and overtreatment, without missing relevant disease, such as adrenocortical carcinomas.”
Fassnacht and colleagues address four main clinical questions in the guideline:
How to assess risk for malignancy?
How to define and manage low-level autonomous cortisol secretion (formerly called subclinical Cushing’s syndrome)?
Who should have surgical treatment and how should it be performed?
What follow-up is indicated if the adrenal incidentaloma is not surgically removed?
The guideline recommends all patients with adrenal incidentalomas undergo imaging to determine whether the mass is benign or malignant at the time of initial detection; noncontrast CT was the recommended method (MRI for children, pregnant women and adults younger than 40 years). If a benign adrenal mass is smaller than 4 cm, no further imaging is required, the researchers wrote.
“The panel felt — despite the limited evidence — confident about the negative predictive value of noncontrast CT to recommend that additional imaging was not necessary when benign characteristics were found in an adrenal mass < 4 cm, especially as additional imaging may also risk false-positive results and significant psychological and financial burden for patients and the health system, respectively,” the researchers wrote. “We acknowledge that the cutoff of 4 cm is not based on good evidence from clinical studies, but the panel felt it necessary to provide clear guidance based on clinical experience.”
In addition, all patients with adrenal incidentalomas should undergo a 1-mg overnight dexamethasone suppression test to exclude cortisol excess. The panel also recommended additional biochemical tests to confirm cortisol secretory autonomy and assess the degree of cortisol secretion, through basal morning plasma adrenocorticotropic hormone (ACTH) and repeated dexamethasone tests between 3 and 12 months in all patients with possible autonomous cortisol secretion.
Any patient with possible autonomous cortisol secretion or autonomous cortisol secretion should also be screened for hypertension and type 2 diabetes, the guideline states.
Adrenalectomy should be the standard of care for unilateral adrenal tumors with clinically significant hormone excess; surgery is not recommended for patients with asymptomatic, nonfunctioning unilateral adrenal mass and obvious benign features on imaging studies.
“The guidelines also provide recommendations on how to address bilateral incidentalomas (both adrenal glands) and tumors in patients with extra-adrenal malignancy (outside of the adrenal glands,” Fassnacht said in the release. “They also clearly define that benign, nonfunctioning masses less than 4 cm in size do not require follow-up imaging. Identification of this group is a major change to prior expert opinion.” – by Regina Schaffer
The European Society of Endocrinology and the European Network for the Study of Adrenal Tumors (via the European Science Foundation) funded this study.