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Adrenal Tumors
Diagnosis/Definition
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An adrenal mass by CT, MRI, or
ultrasound in an asymptomatic or symptomatic patient (Cushing’s
syndrome, pheochromocytoma, aldosteronoma, or other disorders). The
mass may be unilateral or bilateral.
Adrenal masses have an estimated
prevalence of 1.4-8.7% in autopsy studies, 0.6% by CT scan.
It is important to consider pre-test
probability when ordering and interpreting laboratory studies on
this population. For example, less than one in 1,000 patients with
hypertension has a pheochromocytomaa.
Initial Diagnosis
and Management
In addition to searching for signs and symptoms of a functional
adrenal tumor, the history and physical exam should concentrate on
the exclusion of cancers which are commonly metastatic to the
adrenal. These include lung, breast, GI, and prostate cancers.
Syndromes of Multiple Endocrine Neoplasia (MEN) should be in the
diagnostic differential. Pheochromocytoma is suggested by headache, inappropriate and
excessive sweating and palpitations in a patient with paroxysmal or
persistent hypertension. Useful screening labs include urinary
metanephrines, normetanephrines, VMA, and fractionated
catecholamines. These studies require special dietary and medication
considerations. Values greater than 2 x the upper limit of normal
are suggestive of a pheochromocytoma. The measurement of free
metanephrines in plasma is an alternative. Primary hyperaldosteronism is suggested by spontaneous hypokalemia
(K+ < 3.5 in the absence of diuretics or K+ < 3.0 in patients taking
diuretics and potassium supplementation), inappropriate kaluresis
(24 h urine potassium > 30 mEq in face of hypokalemia) and
hypertension. Screen for primary hyperaldosteronism by obtaining a
random plasma aldosterone concentration (PAC) and measuring plasma
renin activity (PRA). Refer any patient with a PAC/PRA > 20 AND PAC
> 15 ng/dL to an endocrinologist. Cushing’s syndrome is suggested by a cushingoid body habitus,
hypertension, glucose intolerance or diabetes, and other
characteristic signs and symptoms. Useful screening tests include
the 1 mg overnight dexamethasone suppression test, assessment of the
circadian production of cortisol, or the collection of 24 hour urine
free cortisol. Some patients with apparently normal endocrine function will have
active adrenal adenomas that have suppressed the contralateral
adrenal. These patients are at risk for an adrenal crisis if the
adenomatous adrenal is surgically removed.
Ongoing
Management and Objectives
Another objective is to identify tumors with a potential for
growth.
The presumed incidental adrenal mass should be re-imaged at 3
months, 6 months, and every 6-12 months thereafter until it is
evident that the mass is stable
Indications for
Specialty Care Referral
Patients with tumors > 3 cm in size or with intramural necrosis,
hemorrhage or irregular margins on imaging should be referred to an
endocrinologist before being sent to a surgeon.
Patients with positive screening tests for pheochromocytoma,
Cushing’s syndrome, or aldosteronoma or those in whom the diagnosis
of these conditions seems probable should be referred to an
endocrinologist before being sent to a surgeon.
Patients with MEN syndromes and their kindred should be referred
to an endocrinologist.
Criteria for
Return to Primary Care
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Exclusion of a functional adrenal
mass.
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Establishment of a plan of care for
the patient with a functional adrenal mass.
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Conclusion of surgical episode for the patient undergoing
adrenalectomy.
Last Review for this Guideline:
October 2007 Referral Guidelines require review every three years.
For more information about the
guidelines, or if you are interested in making changes or new
submissions please contact:
The Clinical Guidelines Administrator.
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