Cushing's Disease - Rare Disease Quick Facts

Cushing's disease is a rare condition due to excess cortisol levels that result from a pituitary tumor secreting adrenocorticotropic hormone (ACTH), which stimulates cortisol secretion.  Cushing’s disease should not be confused with Cushing’s syndrome which is increased cortisol levels but that increase can be due to any number of factors. However, Cushing’s disease is the most common form of Cushing’s syndrome.

Symptoms

The symptoms related to Cushing's disease and Cushing's syndrome are the same, since both are related to an excess of cortisol. Also, symptoms vary extensively among patients and that, with the inherent fluctuation in hormone levels make it difficult to diagnosis both conditions.

Changes in physical characteristics of the body

• Fullness and rounding of the face
• Added fat on back of neck (so-called "buffalo hump")
• Easy bruising
• Purplish stretch marks on the abdomen (abdominal striae)
• Excessive weight gain, especially in abdominal region
• Red cheeks
• Excess hair growth on the face, neck, chest, abdomen and thighs

Changes in physiology/psychology

• Generalized weakness and fatigue
• Menstrual disorder
• Decreased fertility and/or sex drive
• High blood pressure that is often difficult to treat
• Diabetes mellitus
• Mood and behavior disorders

Diagnosis

The early stages of Cushing's disease may be difficult to recognize. However, if it is suspected, diagnosis is generally a 2 stage process. First to determine if cortisol levels are high, and if so, why they are high.

Tests to confirm high cortisol levels:

• 24-hour urine cortisol
• Dexamethasone suppression test (low dose)

Tests to determine cause:

• Blood ACTH level
• Brain MRI
• Corticotropin-releasing hormone test
• Dexamethasone suppression test (high dose)
• Petrosal sinus sampling

Treatment

Surgery

• Most patients with Cushing’s disease undergo surgery to remove the pituitary adenoma offers.
• If the tumor is isolated to the pituitary, cure rates of 80-85% are common.
• If the tumor has spread to nearby organs, cure rates of 50-55% are common.

Medicine (approved orphan drugs)

Signifor (pasireotide)

• Approved for patients with Cushing’s disease for whom pituitary is not an option or surgery has been ineffective.
• Signifor is a somatostatin receptor agonist that leads to inhibition of ACTY secretion (and subsequently decreased cortisol levels).

Korlym (mifepristone)

• Approved for patients with Cushing’s syndrome who have type 2 diabetes or glucose intolerance and have failed surgery (or not candidates for surgery).
• Korlym is a glucocorticoid receptor antagonist which in turn blocks the effects of the high levels of cortisol in the body. Korlym is used to treat high glucose levels due to elevated cortisol.

Medicines used but not indicated for Cushing’s disease include

Mitoden

ketoconazole

Metyrapone

Etomidate

Radiation

• Radiation therapy may be used in some patients and can be very effective in controlling the growth of these tumors.

Prognosis

In most cases, treatment can cure Cushing’s disease. If not treated properly, the chronic hypercortisolism can lead to excess morbidity and mortality due to increased cardiovascular and other risk factors.

For more information

National Library of Medicine, National Institute of Health

Cushing’s Disease Information (provided by Novartis Pharmaceuticals)

Images courtesy of the open access journal Orhanet Journal for Rare Diseases.  Castinetti et al. Orphanet J Rare Dis. 2012 7:41   doi:10.1186/1750-1172-7-41

- See more at: http://www.raredr.com/front-page-medicine/articles/cushings-disease-rare-disease-quick-facts-0

From The Endocrine Society’s Annual Meeting: Pituitary tumor size not definitive for Cushing's

By: SHERRY BOSCHERT, Family Practice News Digital Network

SAN FRANCISCO – The size of a pituitary tumor on magnetic resonance imaging in a patient with ACTH-dependent Cushing’s syndrome can’t differentiate between etiologies, but combining that information with biochemical test results could help avoid costly and difficult inferior petrosal sinus sampling in some patients, a study of 131 cases suggests.

If MRI shows a pituitary tumor larger than 6 mm in size, the finding is 40% sensitive and 96% specific for a diagnosis of Cushing’s disease as the cause of adrenocorticotropic hormone (ACTH)-dependent Cushing’s syndrome, and additional information from biochemical testing may help further differentiate this from ectopic ACTH secretion, Dr. Divya Yogi-Morren and her associates reported at the Endocrine Society’s Annual Meeting.

Pituitary tumors were seen on MRI in 6 of 26 patients with ectopic ACTH secretion (23%) and 73 of 105 patients with Cushing’s disease (69%), with mean measurements of 4.5 mm in the ectopic ACTH secretion group and 8 mm in the Cushing’s disease group. All but one tumor in the ectopic ACTH secretion group were 6 mm or smaller in diameter, but one was 14 mm.

Because pituitary "incidentalomas" as large as 14 mm can be seen in patients with ectopic ACTH secretion, the presence of a pituitary tumor can’t definitively discriminate between ectopic ACTH secretion and Cushing’s disease, said Dr. Yogi-Morren, a fellow at the Cleveland Clinic.

That finding contradicts part of a 2003 consensus statement that said the presence of a focal pituitary lesion larger than 6 mm on MRI could provide a definitive diagnosis of Cushing’s disease, with no further evaluation needed in patients who have a classic clinical presentation and dynamic biochemical testing results that are compatible with a pituitary etiology (J. Clin. Endocrinol. Metab. 2003;88:5593-602). The 6-mm cutoff, said Dr. Yogi-Morren, came from an earlier study reporting that 10% of 100 normal, healthy adults had focal pituitary abnormalities on MRI ranging from 3 to 6 mm in diameter that were consistent with a diagnosis of asymptomatic pituitary adenomas (Ann. Intern. Med. 1994;120:817-20).

A traditional workup of a patient with ACTH-dependent Cushing’s syndrome might include a clinical history, biochemical testing, neuroimaging, and an inferior petrosal sinus sampling (IPSS). Biochemical testing typically includes tests for hypokalemia, measurement of cortisol and ACTH levels, a high-dose dexamethasone suppression test, and a corticotropin-releasing hormone (CRH) stimulation test. Although IPSS is the gold standard for differentiating between the two etiologies, it is expensive and technically difficult, especially in institutions that don’t regularly do the procedure, so it would be desirable to avoid IPSS if it’s not needed in a subset of patients, Dr. Yogi-Morren said.

The investigators reviewed charts from two centers (the Cleveland Clinic and the M.D. Anderson Cancer Center, Houston) for patients with ACTH-dependent Cushing’s syndrome seen during 2000-2012.

ACTH levels were significantly different between groups, averaging 162 pg/mL (range, 58-671 pg/mL) in patients with ectopic ACTH secretion, compared with a mean 71 pg/mL in patients with Cushing’s disease (range, 16-209 pg/mL), she reported. Although there was some overlap between groups in the range of ACTH levels, all patients with an ACTH level higher than 210 pg/mL had ectopic ACTH secretion.

Median serum potassium levels at baseline were 2.9 mmol/L in the ectopic ACTH secretion group and 3.8 mmol/L in the Cushing’s disease group, a significant difference. Again, there was some overlap between groups in the range of potassium levels, but all patients with a baseline potassium level lower than 2.7 mmol/L had ectopic ACTH secretion, she said.

Among patients who underwent a high-dose dexamethasone suppression test, cortisol levels decreased by less than 50% in 88% of patients with ectopic ACTH secretion and in 26% of patients with Cushing’s disease.

Most patients did not undergo a standardized, formal CRH stimulation test, so investigators extracted the ACTH response to CRH in peripheral plasma during the IPSS test. As expected, they found a significantly higher percent increase in ACTH in response to CRH during IPSS in the Cushing’s disease group, ranging up to more than a 1,000% increase. In the ectopic ACTH secretion group, 40% of patients did have an ACTH increase greater than 50%, ranging as high as a 200%-300% increase in ACTH in a couple of patients.

"Although there was some overlap in the biochemical testing, it is possible that it provides some additional proof to differentiate between ectopic ACTH secretion and Cushing’s disease," Dr. Yogi-Morren said.

In the ectopic ACTH secretion group, the source of the secretion remained occult in seven patients. The most common identifiable cause was a bronchial carcinoid tumor, in six patients. Three patients each had small cell lung cancer, a thymic carcinoid tumor, or a pancreatic neuroendocrine tumor. One patient each had a bladder neuroendocrine tumor, ovarian endometrioid cancer, medullary thyroid cancer, or a metastatic neuroendocrine tumor from an unknown primary cancer.

The ectopic ACTH secretion group had a median age of 41 years and was 63% female. The Cushing’s disease group had a median age of 46 years and was 76% female.

Dr. Yogi-Morren reported having no financial disclosures.

sboschert@frontlinemedcom.com

On Twitter @sherryboschert

From Famiiy Practice News

Johns Hopkins Pituitary Patient Day 2013

Johns Hopkins Pituitary Patient Day

Join us on Saturday, September 28, 2013, for the 5th Annual Patient Education Day at the Johns Hopkins Pituitary Center.

When: Saturday, September 28, 2013
Time: 9:30 a.m.
Location:
Johns Hopkins Mt. Washington Conference Center
5801 Smith Avenue
Baltimore, MD 21209
map and directions

Location of the pituitary gland in the human brain (Photo credit: Wikipedia)

Patient Education Day Agenda:
9:30 – 10:00 AM	REGISTRATION
10:00 – 10:25 AM	What is the pituitary gland, where it is located, what it does, and what can go wrong	Gary Wand, MD
10:30 – 10:50 AM	How pituitary tumors can affect your vision	Prem Subramanian, MD, PhD Vivek Patel, MD, PhD
10:50 – 11:10 AM	Cushing disease journey: a patient’s perspective	Stacey Hardy
11:15 – 11:40 AM	Surgery for Pituitary tumors: from very tiny to very large	Alfredo Quinones-Hinojosa, MD Gary Gallia, MD, PhD Alessandro Olivi, MD
11:40 – 12:00 PM	Radiation therapy: when, why, and how	Lawrence Kleinberg, MD Kristen Redmond, MD
12:05 – 12:25 PM	The medications you may be taking (new and old ones): what you need to know	Roberto Salvatori, MD
12:30 – 1:25 PM	Lunch
1:30 – 3:00 PM	PM Round table sessions: 1) Medical therapy (Wand/Salvatori) 2) Surgical therapy (Quinones/Gallia/Olivi) 3) Radiation therapy (Redmond/Kleinberg/Lim) 4) Vision issues (Subramanian/Patel)

*This schedule is subject to change

Please R.S.V.P. by September 13, 2013, vie email (preferred) to PituitaryDay@jhmi.edu  or to Alison Dimick at 410-955-3921.

Reservations will be taken on a first-come, first-serve basis.

Cushing’s Syndrome is Hazardous to Your Health

People with Cushing’s syndrome, even when treated, have higher morbidity and mortality rates that comparable controls. That is the conclusion of a new study published in the June issue of the Journal of Clinical Endocrinology Metabolism. The study by Olaf Dekkers et al, examined data records from the Danish National Registry of Patients and the Danish Civil Registration System of 343 patients with benign Cushing’s syndrome of adrenal or pituitary origin (i.e., Cushing’s disease) and a matched population comparison cohort (n=34,300).  Due to the lengthy delay of many patients being diagnosed with Cushing’s syndrome, morbidity was investigated in the 3 years before diagnosis while  morbidity and mortality were assessed during complete follow-up after diagnosis and treatment.

The study found that mortality was twice as high in Cushing’s syndrome patients (HR 2.3, 95% CI 1.8-2.9) compared with controls over a mean follow-up period of 12.1 years. Furthermore, patients with Cushing’s syndrome were at increased risk for:

• venous thromboembolism (HR 2.6, 95% CI 1.5-4.7)
• myocardial infarction (HR 3.7, 95% CI 2.4-5.5)
• stroke (HR 2.0, 95% CI 1.3-3.2)
• peptic ulcers (HR 2.0, 95% CI 1.1-3.6)
• fractures (HR 1.4, 95% CI 1.0-1.9)
• infections (HR 4.9, 95% CI 3.7-6.4).

The study also found that this increased multimorbidity risk was present before diagnosis indicating that it was due to cortisol overproduction rather than treatment.

Many of the Cushing’s syndrome patients underwent surgery to remove the benign tumor. For this group, the investigators performed a sensitivity analysis of the  long-term mortality and cardiovascular risk in this  subgroup (n=186)  considered to be cured after operation (adrenal surgery and patients with pituitary surgery in combination with a diagnosis of hypopituitarism in the first 6 months after operation).  The risk estimates for mortality (HR 2.31, 95% CI 1.62-3.28), venous thromboembolism (HR 2.03, 95% CI 0.75-5.48), stroke (HR 1.91, 95% CI 0.90-4.05), and acute myocardial infarction (HR 4.38, 95% CI 2.31-8.28) were also increased in this subgroup one year after the operation.

The standard treatment for endogenous Cushing’s syndrome is surgery. This past year, Signifor (pasireotide) was approved for treatment of adults patients with Cushing’s disease for whom pituitary surgery is not an option or has not been curative.  Cushing’s disease, which accounts for the majority of Cushing’s syndrome patients, is defined as the presence of an ACTH producing tumor on the pituitary grand. In the study by Dekker’s et al, the percentage of patients with Cushing’s disease is not known. We look forward to reexamination of this dataset in a few years following the introduction of more treatment options for Cushing’s disease as well as an analysis that explores the differences in mortality/morbidity rates in the different subsets of patients that make of Cushing’s syndrome (Cushing’s disease, ectopic Cushing’s syndrome, Exogenous Cyshing’s syndrome).

References

Dekkers OM, Horvath-Pujo, Jorgensen JOL, et al, Multisystem morbidity and mortality in Cushing’s syndrome: a cohort study. J Clin Endocrinol Metab 2013 98(6): 2277–2284. doi: 10.1210/jc.2012-3582

- See more at: http://www.raredr.com/medicine/articles/cushing%E2%80%99s-syndrome-hazardous-your-health-0