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REVIEW
DIAGNOSIS AND MANAGEMENT OF SURGICAL
ADRENAL DISEASES
DARLENE D. LIN
AND
T
he adrenal glands are paired retroperitoneal
organs situated on the anteromedial surface of
each kidney. The adrenal cortex, constituting 85%
to 90% of the gland, arises embryologically from
the mesoderm and can be subdivided into the zona
glomerulosa, zona fasciculata, and zona reticularis.
Each zone produces steroid hormones from a common precursor, pregnenolone. The zona glomerulosa produces the mineralocorticoid aldosterone,
and the zona reticularis and zona fasciculata produce the glucocorticoid cortisol, as well as androgens and estrogens. Within the cortex lies the adrenal medulla, consisting of catecholamine-secreting
chromaffin cells derived embryologically from neuroectoderm.
Glucocorticoids play key roles in cellular metabolism, immunosuppression, and antiinflammation. Regulated by the hypothalamus-pituitaryadrenal axis, adrenocorticotropin hormone (ACTH)
is secreted by the anterior pituitary in a diurnal
rhythm, with a morning peak and a midnight nadir.
Aldosterone primarily controls salt and fluid balance.
Regulated by the renin-angiotensin-aldosterone
axis, it is synthesized and secreted in response to
increased levels of angiotensin II, hyponatremia, or
hyperkalemia.
The catecholamines epinephrine, norepinephrine, and dopamine are produced from the precursor tyrosine. Once synthesized, catecholamines are
stored in vesicles and released by exocytosis with
stimulation of preganglionic nerves. Responses include inotropy and chronotropy of the heart, vasoconstriction, bronchodilation, lipolysis, increased
metabolic rate, and pupillary dilation.1,2
CUSHING SYNDROME
Cushing syndrome, characterized by Harvey
Cushing in 1932,3 stems from long-term glucocorFrom the Department of Urology, Brigham and Women’s Hospital, Boston, Massachusetts
Reprint requests: Darlene D. Lin, M.D., Department of Urology, Brigham and Women’s Hospital, 45 Francis Street, ASB-II,
3rd Floor, Boston, MA 02115. E-mail: [email protected]
Submitted: October 17, 2004, accepted (with revisions): March
2, 2005
© 2005 ELSEVIER INC.
476
ALL RIGHTS RESERVED
KEVIN R. LOUGHLIN
ticoid exposure. Cushing syndrome is most commonly caused by exogenous therapeutic steroids.
Endogenous causes are classified based on ACTH
elevation. ACTH-dependent forms include pituitary adenoma (Cushing’s disease) and ectopic
ACTH or corticotropin-releasing hormone (CRH)
production. ACTH-independent forms include adrenal adenoma, carcinoma, and hyperplasia. Conditions resulting in hypercortisolism, representing
“pseudo-Cushing” states include major depression, alcoholism, morbid obesity, and poorly controlled diabetes.4 These patients apparently have
an overactive hypothalamus and increased CRH
with appropriate, although blunted, negative feedback on the pituitary.5
The prevalence of endogenous Cushing syndrome is estimated at 2 to 13 cases per million
people annually.5,6 Cushing syndrome accounts
for approximately 0.2% of patients with hypertension7 and 2% to 3% of those with poorly controlled
type 2 diabetes.8 Among the most common causes,
the breakdown is pituitary disease (68% to 70%),
ectopic ACTH (12% to 17%), and adrenal adenoma
or carcinoma (15% to 20%).4 – 6
Symptoms of Cushing syndrome begin gradually, usually with uncontrollable weight gain and
fat redistribution. Patients characteristically develop truncal obesity, moon facies, or a buffalo
hump. Fat may be deposited in unusual places
such as the supraclavicular area, temporal fossa, or
popliteal fossa. Comparison with old photographs
helps with diagnosis. Dermatologic changes include thinning of the skin, easy bruisability or impaired wound healing, facial erythema from telangiectasias, acne, characteristic wide purple striae,
and hirsute or fine villous hair growth. Patients
may experience amenorrhea, oligomenorrhea, or
decreased libido. Proximal muscle wasting is evidenced by difficulty climbing stairs or rising from a
seated position. Hypertension, impaired glucose
tolerance, overt diabetes mellitus, and lipid abnormalities subsequently increase the risk of atherosclerotic cardiovascular disease. Depression is seen
in 50% of patients.6
UROLOGY 66: 476 – 483, 2005
•
0090-4295/05/$30.00
doi:10.1016/j.urology.2005.03.010
FIGURE 1. Diagnosis and management of Cushing syndrome.
BIOCHEMICAL DIAGNOSIS
Once Cushing syndrome is clinically suspected,
biochemical tests can confirm the diagnosis (Fig. 1).
Twenty-four-hour urinary free cortisol is useful as a
screening test. Multiple specimens are needed, because at least one in four specimens will have normal free cortisol in 10% to 15% of patients with
Cushing syndrome.8 Urinary free cortisol has good
sensitivity and specificity, both ranging from 96%
to 100%.9,10
Other tests to differentiate patients with hypercortisolism from normal patients with Cushingoid
features are the low-dose dexamethasone suppression test (LDDST), late-night serum or salivary
cortisol, and the dexamethasone-CRH test. In normal individuals, dexamethasone, a potent glucocorticoid, suppresses the hypothalamic-pituitary axis and decreases levels of ACTH and
cortisol. In the traditional LDDST, 0.5 mg of
dexamethasone is administered orally every 6
hours for 2 days, during which urine is collected
for measurement of 17-hydroxycorticosteroids.
In modified LDDSTs, plasma cortisol may be
measured or the test may be performed overnight with a one-time 1 mg dexamethasone dose.
UROLOGY 66 (3), 2005
The LDDST has a sensitivity of 78% to 86% and a
specificity of 92% to 93%.11
Late-night serum cortisol measurement depends
on the loss of diurnal rhythm even in patients with
mild Cushing syndrome, although the nighttime
nadir is preserved in patients with pseudo-Cushing
syndrome. Studies have reported sensitivity of 96%
to 100% and specificity of 77% to 100%.10,12 This
test has traditionally required an inpatient setting
for 48 hours to avoid falsely elevated cortisol secondary to stress.12 Alternatively, a nighttime salivary specimen, which correlates with plasma free
cortisol, can be obtained at home without undue
stress.13 Midnight salivary cortisol levels show
comparable sensitivity and specificity to plasma
cortisol.9,13
A more recent test combines the LDDST and
CRH stimulation test. In Cushing’s disease, the pituitary adenoma is resistant to low-dose dexamethasone suppression and yet responds to CRH, resulting in increased cortisol. Conversely, pituitary
corticotrophs in patients with adrenal adenomas
will be both suppressed by low doses of dexamethasone and have a blunted response to CRH. A
plasma cortisol measurement 15 minutes after
477
CRH administration yielded 100% sensitivity and
100% specificity compared with patients with
pseudo-Cushing or normal controls.14
DIFFERENTIAL DIAGNOSIS
Once the biochemical diagnosis of Cushing syndrome has been established, the cause must be elucidated. Simultaneous serum measurement of
ACTH and cortisol distinguishes ACTH-independent from ACTH-dependent Cushing syndrome.
Because some patients have cyclical cortisol levels,
multiple samples are recommended.4 If ACTH is
suppressed, indicating ACTH-independent disease, patients proceed to adrenal imaging, usually
noncontrast computed tomography (CT).
If ACTH is elevated on at least one serum measurement, a high-dose dexamethasone suppression test should be performed to distinguish between ACTH-dependent causes. Pituitary-based
disease retains glucocorticoid receptors, so that
with sufficiently high doses of dexamethasone,
ACTH secretion will be suppressed by at least 50%.
Ectopic ACTH production should not respond to
dexamethasone. If the diagnosis remains in doubt,
inferior petrosal sinus sampling, a CRH stimulation test, or a metyrapone stimulation test may be
performed.4,5
Pituitary imaging may be helpful in planning the
surgical approach but does not necessarily assist in
the diagnosis, because 40% to 65% of pituitary adenomas are occult.4,5,8 CT and/or magnetic resonance imaging (MRI) of the chest and abdomen
helps diagnose or localize ectopic ACTH or CRH
sources.
TREATMENT
The treatment of ACTH-independent disease is
unilateral adrenalectomy for adenoma or carcinoma and bilateral adrenalectomy for bilateral hyperplasia. Ectopic disease should be surgically resected when possible. Treatment for pituitary
adenoma is hypophysectomy followed by radiotherapy if this fails. Chemotherapy or radiotherapy
may be necessary if metastases develop.4 Medical
management is useful in several different situations, such as a temporizing approach until definitive surgical therapy, after surgical failure, if a
source cannot be localized, in patients waiting for
pituitary radiotherapy to take effect, as a palliative
measure, or if the patient is not a surgical candidate.
Patients should be monitored to avoid adrenal insufficiency. First-line agents are generally adrenolytic
therapy such as metyrapone, ketoconazole, mitotane,
aminoglutethimide, or etomidate. A second category
of medications, although much more variable in nature and less clearly understood, is neuromodulatory
agents such as dopamine agonist bromocriptine,
5-HT antagonists cyproheptadine or ritanserin, so478
matostatin analogue octreotide, or the gamma-aminobutyric acid agonist sodium valproate. Finally, glucocorticoid antagonists such as mifepristone may be
used cautiously. Bilateral adrenalectomy is a last resort if medical management fails.15
HYPERALDOSTERONISM
Primary aldosteronism, described by Conn in
1955,16 is classically associated with hypertension
and hypokalemia, although many patients are
asymptomatic. Hypokalemia may cause muscle
cramping, palpitations, urinary frequency, nocturia, or polydipsia. Marked hypokalemia manifests
as muscle weakness, tetany, paresthesias, or even
paralysis. Metabolically, patients may have mild
alkalosis, hypernatremia, or high urinary potassium excretion. Hyperaldosteronism should be
suspected in patients with severe hypokalemia after diuretic therapy.17,18
Aldosterone-producing adenomas (APAs) and
bilateral adrenal hyperplasia (BAH) are the most
common causes of primary aldosteronism19,20; less
frequent causes are unilateral adrenal hyperplasia,
adrenocortical carcinoma, glucocorticoid-suppressible hyperaldosteronism, or an ectopic aldosteroneproducing tumor.18,20 Glucocorticoid-suppressible
hyperaldosteronism is autosomal dominantly inherited and results in expression of a chimeric gene
which encodes hybrid steroids.18 Aldosterone production parallels the circadian rhythm of ACTH
and is suppressed by glucocorticoid administration.17
In patients with essential hypertension, the prevalence of primary aldosteronism was traditionally
considered to be 0.5% to 1% when only hypokalemic patients were screened. If all patients with essential hypertension are screened for primary aldosteronism, the prevalence rises significantly, up to
5% to 13%. Although hypokalemia manifests itself
only in patients with severe hyperaldosteronism,
most patients with primary aldosteronism are normokalemic and thus have been previously overlooked.19,20
BIOCHEMICAL DIAGNOSIS
In addition to hypokalemia, patients with primary
hyperaldosteronism characteristically have increased
plasma aldosterone concentration (PAC) and suppressed plasma renin activity (PRA). These tests are
not useful screening tests owing to the diurnal and
day-to-day variation in aldosterone concentration
and the high false-positive rate for suppressed PRA
due to low renin levels in 30% of hypertensive patients. The PAC/PRA ratio is a generally accepted
screening test; it will be persistently elevated in patients with primary hyperaldosteronism despite antihypertensive medications or dietary salt balance.21
UROLOGY 66 (3), 2005
Although this test lacks standardization,22 a PAC/
PRA ratio of greater than 20 or 30 ng/dL per ng/
mL/hr warrants further investigation.17,18 The diagnosis of primary hyperaldosteronism is then
confirmed using an aldosterone suppression test.
In normal patients, sodium loading suppresses aldosterone, but aldosterone remains elevated in patients with hyperaldosteronism. Patients may be
salt loaded orally followed by measurement of 24hour urinary aldosterone excretion. Urinary sodium
documents adequate salt loading. High intake of sodium can aggravate kaliuresis, so potassium must be
repleted. Alternatively, sodium may be administered
intravenously followed by measurement of PAC.
The antihypertensive medications least likely to interfere with these tests are alpha-adrenergic receptor blockers and guanethidine.17,18 These tests will
be inaccurate for patients taking spironolactone or
angiotensin-converting enzyme inhibitors.17
DIFFERENTIAL DIAGNOSIS
As with Cushing syndrome, once the biochemical diagnosis of primary aldosteronism is established, additional testing distinguishes the different subtypes to guide management. The postural
stimulation test entails measurement of PAC after
an 8-hour overnight recumbency and again after 4
hours of erect posture. Patients with APA show less
sensitivity to small changes in angiotensin II that
occurs with upright posture relative to patients
with BAH; a decrease in plasma aldosterone indicates an APA. However, this test has fallen out of
favor, because it does not lateralize a lesion and a
small subset of patients with APA will respond to
angiotensin II and will, therefore, be falsely categorized as having BAH.17,23 Although a positive posture test has a positive predictive value close to
100%, its sensitivity for APA is only 30% to 63%.23
Adrenal CT is recommended; unilateral macroadenomas (more than 1 cm) on CT likely represents APAs, especially in young patients.20 Adrenal
CT scans have a sensitivity of 58% to 75% for detecting APAs.23,24 However, the adrenal glands may
appear normal, have microadenomas, or have bilateral lesions, in which case additional evaluation
is recommended if the clinical suspicion for APA is
high.17,20 Adrenal vein sampling, although invasive
and technically difficult, is the reference standard to
diagnose primary aldosteronism. The rates of successful bilateral catheterization range from 68% to
97%.24 Cortisol is measured to verify that the adrenal
veins were successfully catheterized. Normalized aldosterone levels are compared with an inferior venacaval sample. A ratio of dominant to nondominant
normalized aldosterone of at least 4 is indicative of an
APA or unilateral hyperplasia.17,24
UROLOGY 66 (3), 2005
TREATMENT
Once the subtype of primary hyperaldosteronism has been determined, treatment aimed at minimizing the effects of hypertension or hypokalemia
is implemented. The treatment for APA or unilateral adrenal hyperplasia is adrenalectomy.17 Hypertension completely resolves in approximately
one third of patients.25 BAH and glucocorticoid
suppressible hyperaldosteronism require medical
treatment, usually spironolactone.18
PHEOCHROMOCYTOMA
Pheochromocytomas arise from chromaffin cells
of the adrenal medulla or extraadrenal paraganglionic tissue and secrete catecholamines, usually
epinephrine or norepinephrine. Extraadrenal sites
include the paraaortic sympathetic chain, organ of
Zuckerkandl, renal hilum, urinary bladder, chest,
and neck.26 The annual incidence is 2 to 8 cases per
million people.27,28 They occur with equal frequency between men and women and at any age,
but primarily from age 30 to 50.17 On autopsy series, pheochromocytomas have been found in
0.05% to 0.13% of patients.29,30 Often called the “10%
tumor,” approximately 10% are bilateral, extraadrenal, multifocal, malignant, familial, recur after surgery, or occur in children. Familial syndromes associated with pheochromocytoma include multiple
endocrine neoplasia types IIA and IIB, von HippelLindau, neurofibromatosis, tuberous sclerosis,
Sturge-Weber, and ataxia-telangiectasia.17
Approximately 50% of patients have sustained
hypertension with or without paroxysms, 45% are
normotensive between paroxysms, and the remaining 5% are normotensive.26 Pheochromocytomas occur in 0.05% to 0.5% of hypertensive patients.26,31,32 The paroxysms, or crises, may occur
spontaneously or be triggered by changes in position, increased abdominal pressure, anxiety, exercise, trauma, surgery, labor, or ingestion of certain
foods or drugs. Patients commonly complain of
episodic headaches, tachycardia or palpitations, or
diaphoresis with these paroxysms. Less common
symptoms include nausea, pallor, flushing, dizziness, abdominal pain, dyspnea, angina, tremors,
anxiety, and visual disturbances.17,33 Although
variable among patients, paroxysms tend to occur
in a stereotypical pattern for each patient. Spells
generally last minutes to 1 hour, but can last as
long as 1 week and can occur a few times a year to
hourly.17,26 Patients who should be screened for
pheochromocytoma include those with paroxysms, labile blood pressure, hypertension not amenable to a multidrug regimen, a familial history of
pheochromocytoma or other neuroendocrine disease linked with pheochromocytoma, or a paradoxical rise in blood pressure with antihyperten479
sive medication, especially beta-blockers.26 The
differential diagnosis includes hyperthyroidism,
panic disorder or other anxiety state, menopause,
migraine headaches, and unstable angina.26
DIAGNOSIS
There has been much debate over the most preferred laboratory test. Plasma catecholamines and
24-hour urinary metanephrines or catecholamines
are generally accepted as screening tests; they are
approximately equal in sensitivity and specificity.
The sensitivity has ranged from 71% to 100% and
the specificity from 80% to 100% in various studies. Urinary vanillylmandelic acid has a slightly decreased sensitivity and increased specificity relative to these tests.32–35 False-negative results can
occur, especially if specimens are taken during a normotensive period. Larger tumors may release relatively smaller amounts of catecholamines and higher
amounts of metabolites, because catecholamines are
metabolized within the tumor. Smaller tumors, in
contrast, will release larger amounts of active hormone into the blood stream and correspondingly
fewer metabolites.26 Elevated serum epinephrine
suggests pheochromocytoma in the medulla or organ
of Zuckerkandl, because phenylethanolamine-Nmethyltransferase converts norepinephrine to epinephrine in these sites.2
Recent evidence has supported plasma-free
metanephrine as a diagnostic study, with a sensitivity and specificity of 99% and 89%, respectively.
Free plasma metanephrines levels may be more
consistent, as they are constantly released as tumor
metabolism products. Theoretically, this increases
sensitivity, because it eliminates the need to collect
samples during a paroxysm.35 Some have argued
that the decreased specificity of this test will lead to
an unjustifiable increase in false-negative cases.34
Other investigators have shown promise with fractionated plasma metanephrines.36
Provocative tests include the clonidine suppression and glucagon stimulation tests. The clonidine
suppression test is used when a patient has moderately elevated values of screening plasma catecholamines, between 1000 and 2000 pg/mL. After
oral administration of clonidine, the sympathetic
outflow from the brain will be blocked in neurogenic causes of hypertension. After 3 hours, the
plasma catecholamines will fall to less than 500
pg/mL in patients without pheochromocytoma.
The glucagon stimulation test is useful if the screening studies are negative but clinical suspicion remains high. Glucagon injection stimulates a
pheochromocytoma to secrete catecholamines.
A threefold rise or a rise greater than 2000 pg/mL
is diagnostic. The glucagon stimulation test is
rarely used secondary to the risk of inciting a
hypertensive response. If it is absolutely neces480
sary in an equivocal patient, oral medications such
as prazosin or nifedipine can be given before the
injection to prevent a hypertensive crisis; these
medications will not affect the catecholamine levels measured.26
Pheochromocytomas can be localized using ultrasound, CT, MRI, or scintigraphy. With its low
cost and easy accessibility, ultrasonography is a
useful first-line study; however, its sensitivity is
only 83% to 89%.32,33 CT and MRI are comparable
in localizing intraabdominal lesions, with a sensitivity of 89% to 100%.25,32,33 MRI has an advantage
in detecting extraadrenal disease and so has improved specificity.37 On T2-weighted MRI images,
pheochromocytomas are generally hyperintense,
distinguishing them from most other masses.26,37
Ultrasonography and MRI have been used in pregnant patients with good success. Scintigraphy using 131I-MIBG (metaiodobenzylguanidine) is helpful for localizing complex lesions, such as those
that are extraadrenal, recurrent, multifocal, or malignant. It is generally only used if other imaging
scans have been inconclusive secondary to its cost
and limited availability. 131I-MIBG has a slightly
lower sensitivity than CT or MRI, but near perfect
specificity.26 There is little indication for invasive
angiography with the success of these other imaging modalities. Once localized, fine needle aspiration must be avoided, because it can precipitate a
hypertensive crisis.
TREATMENT
The treatment of pheochromocytoma is operative. Surgical cure is possible as long as there are no
metastases. Patients must be medically optimized
to avoid a hypertensive crisis. This entails treating
the hypertension, expanding the intravascular volume, and controlling any cardiac arrhythmias. An
alpha-adrenergic antagonist such as phenoxybenzamine is primarily used; calcium channel blockers or angiotensin-converting enzyme inhibitors
can be added if necessary. Patients can replenish
salt and fluid orally. If a beta-blocker is needed to
control arrhythmias, it is imperative that the alphablockade be established first. Intraoperatively, care
must be taken to avoid anesthetic agents that precipitate catecholamine secretion.26
Patients are generally followed up postoperatively with biochemical testing; imaging is not routinely necessary. However, no histologic or clinical
criteria have been determined that can distinguish
benign from malignant disease.26
INCIDENTALOMA
Adrenal incidentalomas are defined as clinically
silent adrenal masses found on abdominal imaging
performed for nonadrenal causes. Incidentalomas
UROLOGY 66 (3), 2005
FIGURE 2. Diagnosis and management of adrenal incidentaloma. DHEAS ⫽ dehydroepiandrosterone sulfate; FNA
⫽ fine needle aspiration.
are now the most common adrenal mass encountered.38 Incidentalomas may be significant because
of malignancy or hormonal production. Autopsy
studies have indicated a prevalence ranging from
1% to 8.7% (mean 2.3%). The prevalence increases
with age, from 0.2% for younger patients to 6.9%
for patients older than 70 years old.39 On radiologic series, the prevalence of CT-diagnosed incidentaloma ranges from 0.35% to 4.4%.39,40 Although adrenal adenomas are the most common,
the differential diagnosis includes other tumors
such as adrenocortical carcinoma, pheochromocytoma, soft-tissue tumors, lymphoma, or metastasis,
as well as cysts, hemorrhage, or infection.41 Approximately 16% are hyperfunctioning, 5% represent adrenocortical carcinoma, and 2% are metastases.39 The risk of adrenocortical carcinoma
increases with size. At less than 4 cm, the chance of
malignancy is 2%, from 4.1 to 6 cm, the risk is 6%,
and at greater than 6 cm, the risk is 25%.42 Hyperfunctioning lesions may represent pheochromocytoma, hyperaldosteronoma, mild hypercortisolism,
or virilizing or feminizing tumor.42 Hypercortisolism
is most common, seen in 9% of patients.39
The workup of incidentalomas includes radiologic and biochemical examination (Fig. 2). CT
UROLOGY 66 (3), 2005
scan is the preferred radiologic modality. CT findings indicating benignity include homogenous
round or oval appearance with smooth well-defined borders, less than 10 Hounsfield units, and
size less than 3 cm.43 Hounsfield units less than 10
has a sensitivity of 74% and specificity of 96% for
predicting adenoma.44 Features typical for adrenocortical carcinoma include size larger than 5 cm,
central necrosis, tumor calcification, or evidence of
nodal, hepatic, or venous spread.45 If a mass is indeterminate on CT, MRI or radionuclide scintigraphy can characterize the lesion further. Both opposed-phase chemical shift MRI and scintigraphy
have high accuracy in distinguishing adenomas
from nonadenomas.45 Although ultrasonography
may identify incidentalomas and can distinguish
cystic from solid structures, it has low sensitivity
for smaller lesions and cannot adequately characterize known lesions.43
The biochemical workup of an incidentaloma
consists of the screening tests previously described, including urinary free cortisol, LDDST,
urinary catecholamines and metanephrines, serum
potassium, and the PAC/PRA ratio.42 If needed,
testosterone, dehydroepiandrosterone sulfate, or
estradiol levels can be used to evaluate for viriliz481
ing or feminizing tumors.41 Other primary tumors
should be excluded; percutaneous biopsy is useful
for suspected metastasis.45
Treatment of a clinically hyperfunctioning lesion
is adrenalectomy. Patients with subclinical pheochromocytoma should also undergo surgery because of the risk of a hypertensive crisis, in which
subclinical hypercortisolism or hyperaldosteronism may be carefully observed. Adrenalectomy
should also be performed for nonfunctioning incidentalomas greater than 6 cm or rapidly enlarging
incidentalomas. Masses 4 to 6 cm can be observed
or operated on, depending on the other characteristics. If metastasis is revealed on workup, adrenalectomy has not been shown to be beneficial.42
ADRENOCORTICAL CARCINOMA
Adrenocortical carcinoma is a rare entity representing 0.05% to 0.2%46 of all cancers, with an
annual incidence of 0.5 to 2 per million people.47 It
occurs at any age and has a bimodal distribution,
with peaks at 5 years and 40 to 50 years. There is a
female predominance, and the lesions are bilateral
in 2% to 10% of cases.46,47 Forty-six percent
present with clinically evident endocrine abnormality46,48 and more may be subclinically active.47
Cushing syndrome is seen in 30% to 40% of patients. Virilization occurs in 20% to 30%, but predominantly in children. Hyperaldosteronism and
feminization occur rarely.47 Otherwise, patients
may present with a palpable mass, abdominal or
back pain, fullness, weight loss, nausea, anorexia,
weakness, or fevers.46 – 48 The workup includes
both radiologic and biochemical examination. Adrenalectomy is the mainstay of treatment, even if
the mass cannot be completely excised. Mitotane
has been used adjuvantly or if surgery is not feasible, although the results have been mixed.46,47 The
prognosis is poor, with a recurrence rate of 35% to
85%47 and mean survival of 18 months.46,47
LAPAROSCOPIC ADRENALECTOMY
Laparoscopic adrenalectomy has become increasingly more common since first described in
1992.49 The benefits are typical of laparoscopic
procedures—faster return to regular diet, shorter
hospital stay, shorter convalescence, and decreased analgesic requirement.50 Although most
adrenal masses are amenable to laparoscopy, it is
contraindicated for large adrenocortical carcinomas, especially if local invasion or venous thrombus exists.49
CONCLUSIONS
The complex hormonal function of the adrenal
glands encompasses many aspects of normal
bodily function. An adrenal mass may present as an
482
incidental finding or with symptoms of hormonal
excess. Biochemical function and the risk of malignancy must be evaluated when considering adrenalectomy.
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