New discoveries offer possible Cushing’s disease cure

Posted on April 27, 2019 by MaryO

LOS ANGELES — More than a century has passed since the neurosurgeon and pathologist Harvey Cushing first discovered the disease that would eventually bear his name, but only recently have several key discoveries offered patients with the condition real hope for a cure, according to a speaker here.

There are several challenges clinicians confront in the diagnosis and treatment of Cushing’s disease, Shlomo Melmed, MB, ChB, FRCP, MACP, dean, executive vice president and professor of medicine at Cedars-Sinai Medical Center in Los Angeles, said during a plenary presentation. Patients who present with Cushing’s disease typically have depression, impaired mental function and hypertension and are at high risk for stroke, myocardial infarction, thrombosis, dyslipidemia and other metabolic disorders, Melmed said. Available therapies, which range from surgery and radiation to the somatostatin analogue pasireotide (Signifor LAR, Novartis), are often followed by disease recurrence. Cushing’s disease is fatal without treatment; the median survival if uncontrolled is about 4.5 years, Melmed said.

“This truly is a metabolic, malignant disorder,” Melmed said. “The life expectancy today in patients who are not controlled is apparently no different from 1930.”

The outlook for Cushing’s disease is now beginning to change, Melmed said. New targets are emerging for treatment, and newly discovered molecules show promise in reducing the secretion of adrenocorticotropic hormone (ACTH) and pituitary tumor size.

“Now, we are seeing the glimmers of opportunity and optimism, that we can identify specific tumor drivers — SST5, [epidermal growth factor] receptor, cyclin inhibitors — and we can start thinking about personalized, precision treatment for these patients with a higher degree of efficacy and optimism than we could have even a year or 2 ago,” Melmed said. “This will be an opportunity for us to broaden the horizons of our investigations into this debilitating disorder.”

Challenges in diagnosis, treatment

Overall, about 10% of the U.S. population harbors a pituitary adenoma, the most common type of pituitary disorder, although the average size is only about 6 mm and 40% of them are not visible, Melmed said. In patients with Cushing’s disease, surgery is effective in only about 60% to 70% of patients for initial remission, and overall, there is about a 60% chance of recurrence depending on the surgery center, Melmed said. Radiation typically leads to hypopituitarism, whereas surgical or biochemical adrenalectomy is associated with adverse effects and morbidity. Additionally, the clinical features of hypercortisolemia overlap with many common illnesses, such as obesity, hypertension and type 2 diabetes.

“There are thousands of those patients for every patient with Cushing’s disease who we will encounter,” Melmed said.

The challenge for the treating clinician, Melmed said, is to normalize cortisol and ACTH with minimal morbidity, to resect the tumor mass or control tumor growth, preserve pituitary function, improve quality of life and achieve long-term control without recurrence.

“This is a difficult challenge to meet for all of us,” Melmed said.

Available options

Pituitary surgery is typically the first-line option offered to patients with Cushing’s disease, Melmed said, and there are several advantages, including rapid initial remission, a one-time cost and potentially curing the disease. However, there are several disadvantages with surgery; patients undergoing surgery are at risk for postoperative venous thromboembolism, persistent hypersecretion of ACTH, adenoma persistence or recurrence, and surgical complications.

Second-line options are repeat surgery, radiation, adrenalectomy or medical therapy, each with its own sets of pros and cons, Melmed said.

“The reality of Cushing’s disease — these patients undergo first surgery and then recur, second surgery and then recur, then maybe radiation and then recur, and then they develop a chronic illness, and this chronic illness is what leads to their demise,” Melmed said. “Medical therapy is appropriate at every step of the spectrum.”

Zebrafish clues

Searching for new options, Melmed and colleagues introduced a pituitary tumor transforming gene discovered in his lab into zebrafish, which caused the fish to develop the hallmark features of Cushing’s disease: high cortisol levels, diabetes and cardiovascular disease. In the fish models, researchers observed that cyclin E activity, which drives the production of ACTH, was high.

Melmed and colleagues then screened zebrafish larvae in a search for cyclin E inhibitors to derive a therapeutic molecule and discovered R-roscovitine, shown to repress the expression of proopiomelanocortin (POMC), the pituitary precursor of ACTH.

In fish, mouse and in vitro human cell models, treatment with R-roscovitine was associated with suppressed corticotroph tumor signaling and blocked ACTH production, Melmed said.

“Furthermore, we asked whether or not roscovitine would actually block transcription of the POMC gene,” Melmed said. “It does. We had this molecule (that) suppressed cyclin E and also blocks transcription of POMC leading to blocked production of ACTH.”

In a small, open-label, proof-of-principal study, four patients with Cushing’s disease who received roscovitine for 4 weeks developed normalized urinary free cortisol, Melmed said.

Currently, the FDA Office of Orphan Products Development is funding a multicenter, phase 2, open-label clinical trial that will evaluate the safety and efficacy of two of three potential doses of oral roscovitine (seliciclib) in patients with newly diagnosed, persistent or recurrent Cushing disease. Up to 29 participants will be treated with up to 800 mg per day of oral seliciclib for 4 days each week for 4 weeks and enrolled in sequential cohorts based on efficacy outcomes.

“Given the rarity of the disorder, it will probably take us 2 to 3 years to recruit patients to give us a robust answer,” Melmed said. “This zebrafish model was published in 2011, and we are now in 2019. It has taken us 8 years from publication of the data to, today, going into humans with Cushing’s. Hopefully, this will light the pathway for a phase 2 trial.”

‘ Offering optimism’

Practitioners face a unique paradigm when treating patients with Cushing’s disease, Melmed said. Available first- and second-line therapy options often are not a cure for many patients, who develop multimorbidity and report a low quality of life.

“Then, we are kept in this difficult cycle of what to do next and, eventually, running out of options,” Melmed said. “Now, we can look at novel, targeted molecules and add those to our armamentarium and at least offer our patients the opportunity to participate in trials, or at least offer the optimism that, over the coming years, there will be a light at the end of the tunnel for their disorder.”

Melmed compared the work to Lucas Cranach’s Fons Juventutis (The Fountain of Youth). The painting, completed in 1446, shows sick people brought by horse-drawn ambulance to a pool of water, only to emerge happy and healthy.

“He was imagining this ‘elixir of youth’ (that) we could offer patients who are very ill and, in fact, that is what we as endocrinologists do,” Melmed said. “We offer our patients these elixirs. These Cushing’s patients are extremely ill. We are trying with all of our molecular work and our understanding of pathogenesis and signaling to create this pool of water for them, where they can emerge with at least an improved quality of life and, hopefully, a normalized mortality. That is our challenge.” – by Regina Schaffer

Reference:

Melmed S. From zebrafish to humans: translating discoveries for the treatment of Cushing’s disease. Presented at: AACE Annual Scientific and Clinical Congress; April 24-28, 2019; Los Angeles.

Disclosure: Melmed reports no relevant financial disclosures.

 

From https://www.healio.com/endocrinology/neuroendocrinology/news/online/%7B585002ad-640f-49e5-8d62-d1853154d7e2%7D/new-discoveries-offer-possible-cushings-disease-cure

Filed under: AACE Annual Scientific and Clinical Congress, Cushing's, Meetings and Conferences, pituitary, symptoms, Treatments | Tagged: , , , , , , , , , , , , | Leave a comment »

Mild Cases of Cushing’s Syndrome Present Diagnostic Challenges

Posted on August 16, 2017 by MaryO

By Tori Rodriguez, MA, LPC

 

In the early 20th century, the term “pluriglandular syndrome” was coined by Harvey Cushing to describe the disorder that results from chronic tissue exposure to excessive levels of glucocorticoids.1 Now called Cushing’s syndrome, the condition affects an estimated 10-15 million people annually, most often women and individuals between the ages of 20 and 50 years.2 Risk factors and common comorbidities include hypertension, obesity, osteoporosis, uncontrolled diabetes, depression, and anxiety.3

Presentation

The clinical presentation of the disorder is heterogenous and varies by sex, age, and disease severity. Common signs and symptoms include central adiposity, roundness of the face or extra fat around the neck, thin skin, impaired short-term memory and concentration, irritability, hirsutism in women, fatigue, and menstrual irregularity.4 Because each of these features may be observed in a wide range of other conditions, it may be difficult to diagnose cases that are not severe.

“It can be challenging to differentiate the milder forms from pseudo-Cushing’s states,” which are characterized by altered cortisol production and many of the same clinical features as Cushing’s syndrome, according to Roberto Salvatori, MD, the medical director of the Johns Hopkins Pituitary Center, Baltimore, Maryland. These may include alcoholism, obesity, eating disorders, and depression. “Because Cushing’s can cause depression, for example, it is sometimes difficult to determine which came first,” he says. In these states, however, hypercortisolism is believed to be driven by increased secretion of hypothalamic corticotropin-releasing hormone, which is suppressed in Cushing’s syndrome.5

Causes and Diagnosis

If Cushing’s syndrome is suspected on the basis of the patient’s physical appearance, the diagnostic workup should include a thorough medical history, physical exam, and 1 or more of the following tests to establish hypercortisolism: the 24-hour urinary cortisol test, the low-dose dexamethasone suppression test, or the late-night salivary cortisol test. “We sometimes use 2 or 3 of these tests since 1 may not accurately reflect cortisol production in a particular patient,” Dr Salvatori notes. The next step is to determine the source of the hypercortisolism, which may involve the high-dose dexamethasone suppression test, magnetic resonance imaging, or petrosal sinus sampling.2

Medication is the most common cause of Cushing’s syndrome. These iatrogenic or exogenous cases typically result from corticosteroids administered for conditions such as asthma, allergies, and autoimmune disorders.6 More rarely, the disorder can be caused by the use of medroxyprogesterone. In these cases, corticosteroids should be reduced or discontinued under medical care, if possible.

Endogenous Cushing’s syndrome results from the presence of benign or malignant tumors on the adrenal or pituitary glands or elsewhere in the body. These tumors can interfere with the adrenal glands’ production of cortisol that is usually prompted by the adrenocorticotropic hormone (ACTH) released by the pituitary gland.6 There are 3 different mechanisms by which the process can occur.

  • Pituitary adenomas, which account for approximately 70% of endogenous cases of Cushing’s syndrome, secrete ACTH and stimulate additional cortisol production. Because of the large proportion of cases this condition represents, it is specifically referred to as Cushing’s disease. It is more common in women than men (with a ratio of 3 to 4:1), although in pediatric patients, it occurs more frequently in boys vs girls.5
  • Adrenal tumors (adenomas, malignant tumors, or micronodular hyperplasia) produce cortisol in their own tissue in addition to the amount produced by the adrenal glands. These tumors, which cause approximately 15% of endogenous Cushing’s syndrome cases, are more common in children vs adults and in women vs men.
  • Benign or malignant tumors elsewhere in the body, most often the lungs, thyroid, thymus, and pancreas, secrete ACTH and trigger the excessive release of cortisol. An estimated 15% of endogenous cases are attributed to these types of tumors.

Treatment

Surgery is the first-line treatment for Cushing’s syndrome. “We first want to try to figure out the cause of the disorder,” Dr Salvatori says. “Ideally, treatment involves surgery to remove the tumor that is causing it.”

When surgery is unsuccessful, contraindicated, or delayed, other treatment options include radiation or medications that inhibit cortisol, modulate the release of ACTH, or inhibit steroidogenesis.5 Bilateral adrenalectomy may be indicated for patients who do not respond to medication or other surgery.

If surgical resection of the tumor is successful, then “all of the comorbidities reverse, but if it is unsuccessful or must be delayed, you would treat each comorbidity” with the appropriate medication; for example, antihypertensives for high blood pressure and antidiabetic medications for diabetes, Dr Salvatori advises. In severe cases, prophylactic antibiotics may be indicated for the prevention of severe infections such as pneumonia.

It is also important to inquire about and address psychiatric symptoms related to Cushing’s syndrome, even in patients who are in remission. It has been proposed that the chronic hypercortisolism and dysfunction of the HPA axis may “lead to structural and functional changes in the central nervous system, developing brain atrophy, particularly in the hippocampus, which may determine the high prevalence of psychiatric disorders, such as affective and anxiety disorders or cognitive dysfunctions,” according to a recently published paper on the topic.7 Patients should be screened with self-report questionnaires such as the Beck Depression Inventory and the Hospital Anxiety and Depression Scale, and management of psychiatric symptoms may include patient education, psychotropic medications, and referral to a mental health professional.

Future Directions

Several trials are currently planned or underway, including a phase 2 randomized, double-blind, placebo-controlled study of an oral medication called ATR-101 by Millendo Therapeutics, Inc. (ClinicalTrials.gov identifier: NCT03053271). In addition to the need for novel medical therapies, refined imaging techniques could improve surgical success rates in patients with Cushing’s disease in particular, according to Dr Salvatori. “A significant portion of these patients have tumors too small to be detected by MRI, and the development of more sensitive MRI could improve detection and provide a surgical target” for neurosurgeons treating the patients, he says.

Summary

Milder cases of Cushing’s syndrome present diagnostic challenges are a result overlapping features with various other conditions. Diagnosis may require careful observation as well as biochemical and imaging tests.

RELATED ARTICLES

References

  1. Loriaux DL. Diagnosis and differential diagnosis of Cushing’s syndrome. N Engl J Med. 2017;376:1451-1459. doi:10.1056/NEJMra1505550
  2. American Association of Neurological Surgeons. Cushing’s syndrome/disease. http://www.aans.org/Patients/Neurosurgical-Conditions-and-Treatments/Cushings-Disease. Accessed August 1, 2017.
  3. León-Justel A, Madrazo-Atutxa A, Alvarez-Rios AI, et al. A probabilistic model for cushing’s syndrome screening in at-risk populations: a prospective multicenter study. J Clin Endocrinol Metab. 2016;101:3747-3754. doi:10.1210/jc.2016-1673
  4. The Pituitary Society. Cushing’s syndrome and disease–symptoms. https://pituitarysociety.org/patient-education/pituitary-disorders/cushings/symptoms-of-cushings-disease-and-cushings-syndrome. Accessed August 1, 2017.
  5. Sharma ST, Nieman LK, Feelders RA. Cushing’s syndrome: epidemiology and developments in disease management. Clin Epidemiol. 2015;7:281-293. doi:10.2147/CLEP.S44336
  6. National Institutes of Health: Eunice Kennedy Shriver National Institute of Child Health and Human Development. What causes Cushing’s syndrome?https://www.nichd.nih.gov/health/topics/cushing/conditioninfo/pages/causes.aspx. Accessed August 1, 2017.
  7. Santos A, Resmini E, Pascual JC, Crespo I, Webb SM. Psychiatric symptoms in patients with Cushing’s syndrome: prevalence, diagnosis and management. Drugs. 2017;77:829-842. doi:10.1007/s40265-017-0735-z

From http://www.endocrinologyadvisor.com/adrenal/cushings-syndrome-diagnosis-treatment/article/682302/

Filed under: adrenal, Cushing, Cushing's, pituitary | Tagged: , , , , , , , , , , , , , , , | Leave a comment »

Cataloging Cushing’s Patients

Posted on June 3, 2017 by MaryO

The Cushing/Whitney Medical Library is pleased to announce the completion of a grant funded to catalog 2,600 glass plate negatives from the Cushing Brain Tumor Registry.  The grant proposal, “Rethinking Early Neurosurgery: The Harvey Cushing Collection,” was funded through a National Network of Libraries of Medicine-New England Region Knowledge/Data Management Award.  From mid-February through April 30th 2017,  a team of graduate and undergraduate students carefully inputted information on over 3,000 glass plate negatives into the Cushing Center database, exceeding the estimated amount in the grant. The negatives depict Dr. Harvey Cushing’s patients, including histology.

Harvey Cushing, the pioneer and father of neurosurgery, was born on April 8, 1869 in Cleveland, Ohio. He graduated from Yale University in 1891, studied medicine at Harvard Medical School and received his medical degree in 1895. In 1896, he moved to Johns Hopkins Hospital where he trained to become a surgeon under the watchful eye of William S. Halstead, the father of American surgery. By 1899 Cushing became interested in surgery of the nervous system and began his career in neurosurgery. During his tenure at Johns Hopkins, there were countless discoveries in the field of neuroscience.

In 1913, Cushing relocated to Harvard as the surgeon-in-chief at the new Peter Bent Brigham Hospital. Cushing continued to operate on several hundred patients a year with remarkable results.  In addition he was relentless in his recording of patient histories and continued his careful attention to the details and documentation of each surgery.

In 1932 Harvey Cushing retired and in 1933 he agreed to join the staff at Yale University, his alma mater, as the Sterling Professor of Medicine in Neurology.  Cushing died in 1939.

The negatives are undergoing rehousing and digitization, and will be made available for research through the Cushing Center database, which brings multiple parts of Harvey Cushing’s work together in one place.  The database, still in development, will allow researchers to explore Cushing’s medical work and patients.  Please contact Terry Dagradi, Cushing Center Coordinator, for details.

 

From http://library.medicine.yale.edu/blog/cushing-center/cataloging-cushings-patients

Filed under: Cushing, Cushing's, Helpful Doctors, pituitary | Tagged: , , , , , | Leave a comment »

Diagnosis and Differential Diagnosis of Cushing’s Syndrome

Posted on April 18, 2017 by MaryO

D. Lynn Loriaux, M.D., Ph.D.

N Engl J Med 2017; 376:1451-1459April 13, 2017DOI: 10.1056/NEJMra1505550

More than a century ago, Harvey Cushing introduced the term “pluriglandular syndrome” to describe a disorder characterized by rapid development of central obesity, arterial hypertension, proximal muscle weakness, diabetes mellitus, oligomenorrhea, hirsutism, thin skin, and ecchymoses.1 Cushing knew that this syndrome was associated with adrenal cancer,2 and he suspected that some cases might have a pituitary component.

On September 6, 1911, he performed a craniotomy on one of his patients (referred to as Case XLV) but found no pituitary tumor.3 In his description of the case, he goes on to say that “we may perchance be on the way toward the recognition of the consequences of hyperadrenalism.”2 With time, it became clear that the disorder could be caused by small basophilic adenomas of the pituitary gland,4 and the pluriglandular syndrome became known as Cushing’s syndrome.

Fuller Albright provided the next conceptual advance in an extraordinary report, published in the first volume of the Laurentian Hormone Conference, “The Effects of Hormones on Osteogenesis in Man”5:

It has been our concept that protoplasm in general, like the protoplasmic matrix of bone, is constantly being anabolized and catabolized at one and the same time; a factor which increases catabolism would lead to very much the same net result as a factor which inhibits anabolism, but there would be some differences; it is my belief that the “S” hormone [cortisol] is anti-anabolic rather than catabolic. . . . The anti-anabolism . . . is contrasted with the increased anabolism due to an excess of the “N” hormone [testosterone] in the adreno-genital syndrome. This anti-anabolism of protoplasm in Cushing’s syndrome accounts for not only the osteoporosis, but the muscular weakness, the thin skin, probably the easy bruisability, and possibly the atrophy of the lymphoid tissues and thymus.

Nonetheless, in the intervening years, the physical examination of patients suspected to have glucocorticoid excess focused on the anabolic changes, essentially to the exclusion of the antianabolic changes. With the rapid increase in the rate of obesity in the general population, Cushing’s syndrome can no longer be reliably separated from the metabolic syndrome of simple obesity on the basis of anabolic signs alone. However, the antianabolic changes in Cushing’s syndrome are very effective in making this distinction. This review focuses on the problems introduced into the diagnosis and differential diagnosis of Cushing’s syndrome by the obesity epidemic and on ways to alter the traditional approach, using the antianabolic changes of excess cortisol to separate patients with Cushing’s syndrome from obese patients with the insulin-resistant metabolic syndrome.

PHYSICAL EXAMINATION

Andreas Vesalius (1514–1564) published his transformational work on human anatomy, De Humani Corporis Fabrica Libri Septem, in 1543. It is the book that corrected many of Galen’s anatomical errors. The book was met with considerable hostility. As an example, Jacobus Sylvius (Jacques Dubois, 1478–1555), the world’s leading anatomist at the time and Vesalius’s former mentor, on being asked his opinion of the work, replied, “Galen is not wrong. It is man that has changed, and not for the better.”6 This was not true then, but it is true now.

Approximately one third of the U.S. population is obese. The worldwide prevalence of the metabolic syndrome among obese persons is conservatively estimated at 10%; that is, approximately 12 million people have the obesity-related metabolic syndrome.7,8 The clinical picture of this syndrome is almost the same as that of Cushing’s syndrome.9,10 The prevalence of undiagnosed Cushing’s syndrome is about 75 cases per 1 million population, or 24,000 affected persons. On the basis of these prevalence estimates, the chance that a person with obesity, hypertension, hirsutism, type 2 diabetes, and dyslipidemia has Cushing’s syndrome is about 1 in 500. In Harvey Cushing’s era, when obesity was rare, making the diagnosis of Cushing’s syndrome was the most certain aspect of the management of this disorder. Today, making the diagnosis is the least certain aspect in the care of patients with Cushing’s syndrome.

The metabolic syndrome caused by glucocorticoid hypersecretion can be differentiated from the obesity-associated metabolic syndrome with the use of a careful assessment of Albright’s antianabolic effects of cortisol. These effects — osteopenia, thin skin, and ecchymoses — are present in patients with Cushing’s syndrome but not in patients with simple obesity.

Patients in whom osteoporosis is diagnosed radiographically are more likely to have Cushing’s syndrome than those who do not have osteoporosis, with a positive likelihood ratio of 11.11-13 Today, a z score of −2 at the lumbar spine supports this criterion. Skinfold thickness is conveniently measured with an electrocardiographic caliper that has the points dulled with a sharpening stone and the screws tightened so that the gap is maintained when the caliper is removed from the skinfold. The skin over the proximal phalanx of the middle finger of the nondominant hand is commonly used for this measurement

 

(Figure 1 FIGURE 1Measurement of Skinfold Thickness.). A thickness of less than 2 mm is considered to be thin skin. Patients who have thin skin are more likely to have Cushing’s syndrome, with a positive likelihood ratio of 116

 

(Figure 2 FIGURE 2 Comparison of Skinfold Thickness in Patients with Cushing’s Syndrome and Those with Other Conditions Related to Insulin Resistance.).13-15 Finally, patients who have three or more ecchymoses that are larger than 1 cm in diameter and not associated with trauma such as venipuncture are more likely to have Cushing’s syndrome than are patients without such findings, with a positive likelihood ratio of 4.13,16

If we know the prevalence of undiagnosed Cushing’s syndrome in the population of persons with the obesity-related metabolic syndrome, we can begin to calculate the probability that a person has Cushing’s syndrome, using the likelihood ratios for the antianabolic features observed on physical examination. Likelihood ratios can be converted into probabilities with the use of Bayes’ theorem. This conversion is markedly facilitated by the Fagan nomogram for this purpose.17

The prevalence of undiagnosed Cushing’s syndrome is not known, but it can be estimated. Two persons per 1 million population die from adrenal cancer every year.18 The current life span for patients with adrenocortical carcinoma, after diagnosis, is between 2 and 4 years.19,20 Allowing 3 years to make the diagnosis, the prevalence of undiagnosed Cushing’s syndrome is 6 cases per million. In most case series of Cushing’s syndrome, an average of 8% of patients have adrenal carcinoma.21 If 6 per million is 8% of the group, the total Cushing’s syndrome group is 75 persons per million, or 24,000 persons. If all 24,000 patients are included in the metabolic syndrome group, comprising 12 million people, the prevalence of Cushing’s syndrome is 0.002, or 0.2%. With a probability of 0.2% and a likelihood ratio of 116 for thin skin, 18 for osteopenia, and 4 for ecchymoses, the probability that a patient with these three findings has Cushing’s syndrome is 95%.

URINARY FREE CORTISOL

The diagnosis of all endocrine diseases requires a clinical presentation that is compatible with the disease, as well as identification of the pathophysiological cause. An assessment for excess glucocorticoid effects can be made by measuring the 24-hour urinary free cortisol level.22 There are two kinds of free cortisol: plasma protein-unbound cortisol and cortisol unconjugated to sulfuric or hyaluronic acid. Protein-unbound cortisol is filtered in the glomerulus and then reabsorbed in the collecting system. About 3% of filtered cortisol ends up in the urine. This free cortisol in the urine is unconjugated. Thus, the urinary free cortisol level is a direct reflection of the free, bioactive cortisol level in plasma. The free cortisol level is quantified in a 24-hour urine sample by averaging the increased secretion of cortisol in the morning and the decreased secretion in the afternoon and at night. Urinary creatinine is also measured to determine whether the collection is complete. Creatinine levels of less than 1.5 g per day for men and less than 1 g per day for women indicate incomplete collection, and the test should be repeated in patients with these levels.

Unconjugated cortisol can be extracted directly from urine with a nonpolar lipid solvent. After extraction, the cortisol is purified by means of high-pressure liquid chromatography and then quantified with a binding assay, usually radioimmunoassay. Free cortisol also can be quantitated directly by means of mass spectroscopy. The urinary free cortisol assay of choice uses high-pressure liquid chromatographic separation followed by mass spectrometric quantitation.23 With the use of this assay, the urinary free cortisol level in healthy adults ranges from 8 to 51 μg per 24 hours (mean [±SD], 23±8). Clinical depression increases urinary free cortisol excretion, and most studies show that the level of urinary free cortisol ranges from 10 to 60 μg per day in patients with typical clinical signs and symptoms of depression. If we use 60 μg per day as the cutoff between normal values (<60 μg per day) and elevated values (≥60 μg per day), urinary free cortisol excretion of 62 μg per day or more has a positive likelihood ratio of 11.24 Thus, in a patient presenting with obesity, hypertension, type 2 diabetes, and hirsutism who has thin skin, osteopenia, ecchymoses, and an elevated urinary free cortisol level, the probability of Cushing’s syndrome is 1 (100%). For such patients, the clinician should move directly to a differential diagnostic evaluation.

DEXAMETHASONE-SUPPRESSION TEST

The dexamethasone-suppression test is commonly used in the diagnosis of Cushing’s syndrome. This test was developed by Grant Liddle in the early 1960s as a differential diagnostic test to separate corticotropin-dependent from corticotropin-independent Cushing’s syndrome. This is now done by measuring the plasma corticotropin level. Unfortunately, dexamethasone suppression has continued to be used as a screening test for Cushing’s syndrome.

The control group for this test comprises patients with obesity and depression in whom cortisol secretion is not suppressed in response to an oral dose of 1 mg of dexamethasone at midnight. Of the current U.S. population of 360 million people, approximately one third (120 million people) are obese. Of those who are obese, 10% (12 million people) have depression. In half these patients (6 million people), the plasma cortisol level will not be suppressed in response to a dexamethasone challenge. On the basis of my estimate of the current prevalence of undiagnosed Cushing’s syndrome (24,000 cases) and the estimate of the at-risk population (6 million persons), the positive predictive value of the dexamethasone-suppression test is only 0.4%. Thus, this test should not influence what the physician does next and should no longer be used for this purpose.

OUTLIERS

For patients with convincing evidence of Cushing’s syndrome on physical examination and an elevated 24-hour urinary free cortisol level, the differential diagnostic process outlined below should be initiated. However, a small group of patients will not meet these criteria.

Some patients have a strongly positive physical examination but low or zero urinary free cortisol excretion. Plasma corticotropin levels are suppressed in these patients. These patients are receiving exogenous glucocorticoids. The glucocorticoid must be identified, and a plan must be made for its discontinuation. Sometimes the glucocorticoid is being given by proxy (e.g., by a parent to a child), and no history of glucocorticoid administration can be found. Nevertheless, the glucocorticoid must be identified and discontinued.

Other patients have few or no clinical signs of Cushing’s syndrome but do have elevated urinary free cortisol excretion. Plasma corticotropin is measurable in these patients. They are usually identified during an evaluation for arterial hypertension. All such patients should undergo inferior petrosal sinus sampling to determine the source of corticotropin secretion. Ectopic sources are almost always neoplastic and are usually in the chest.25 Patients with eutopic secretion usually have the syndrome of generalized glucocorticoid resistance.26

Finally, a few patients have convincing findings on physical examination coupled with a normal urinary free cortisol level. In such cases, the clinician should make sure that urinary free cortisol is being measured with high-performance liquid chromatography and mass spectrometry, that renal function is normal, and that the collections are complete. “Periodic” Cushing’s syndrome must be ruled out by measuring urinary free cortisol frequently over the course of a month.27 If these efforts fail, the patient should be followed for a year, with urinary free cortisol measurements performed frequently. No additional tests should be performed until the situation is sorted out. More tests would be likely to lead to an unnecessary surgical procedure.

DIFFERENTIAL DIAGNOSIS

The differential diagnosis of Cushing’s syndrome is shown in Figure 3

FIGURE 3Differential Diagnosis of Cushing’s Syndrome.. If plasma corticotropin is measurable, the disease process is corticotropin-dependent. If corticotropin is not measurable, the process is corticotropin-independent.

Corticotropin-dependent causes of Cushing’s syndrome are divided into those in which the corticotropin comes from the pituitary (eutopic causes) and those in which the corticotropin comes from elsewhere (ectopic causes). This differentiation is made with the measurement of corticotropin in inferior petrosal sinus plasma and the simultaneous measurement of corticotropin in peripheral (antecubital) plasma immediately after corticotropin-releasing hormone stimulation of pituitary corticotropin secretion. In samples obtained 4, 6, and 15 minutes after stimulation with corticotropin-releasing hormone, eutopic corticotropin secretion is associated with a ratio of the central-plasma corticotropin level to the peripheral-plasma corticotropin level of 3 or more. Ectopic corticotropin secretion is associated with a central-to-peripheral corticotropin ratio of less than 3. The positive predictive value of this test is 1 (Figure 4

FIGURE 4Maximal Ratio of Corticotropin in Inferior Petrosal Sinus Plasma to Corticotropin in Peripheral Plasma in Patients with Cushing’s Syndrome, Ectopic Corticotropin Secretion, or Adrenal Disease.).28

Although some authorities suggest that inferior petrosal sinus sampling can safely be bypassed in patients with corticotropin-dependent Cushing’s syndrome and a well-defined pituitary adenoma, I disagree. The incidence of nonfunctioning pituitary microadenomas is between 15% and 40%.29 This means that up to 40% of patients with ectopic secretion of corticotropin have an incidental pituitary abnormality. If it is assumed that the pituitary abnormality is responsible for corticotropin secretion, 15 to 40% of patients with ectopic secretion of corticotropin will be misdiagnosed and submitted to a transsphenoidal exploration of the sella turcica and pituitary gland. The prevalence of ectopic corticotropin secretion in the population of patients with undiagnosed Cushing’s syndrome is about 10%, accounting for 2400 patients. Up to 40% of these patients, or 960, have an incidental pituitary tumor. The mortality associated with transsphenoidal microadenomectomy is 1%.30 If all 360 to 960 patients undergo this procedure, there will be up to 10 deaths from an operation that can have no benefit. For this reason alone, all patients with corticotropin-dependent Cushing’s syndrome should undergo inferior petrosal sinus sampling to confirm the source of corticotropin secretion before any surgical intervention is contemplated.

Patients with eutopic corticotropin secretion are almost certain to have a corticotropin-secreting pituitary microadenoma. An occasional patient will have alcohol-induced pseudo–Cushing’s syndrome. The slightest suggestion of alcoholism should lead to a 3-week abstinence period before any surgery is considered.31

Patients with ectopic corticotropin secretion are first evaluated with computed tomography (CT) or magnetic resonance imaging (MRI) of the chest. In two thirds of these patients, a tumor will be found.25 If nothing is found in the chest, MRI of the abdominal and pelvic organs is performed. If these additional imaging studies are also negative, there are two options: bilateral adrenalectomy or blockade of cortisol synthesis. If blockade is chosen, the patient should undergo repeat scanning at 6-month intervals.32 If no source is found by the end of the second year, it is unlikely that the source will ever be found, and bilateral adrenalectomy should be performed for definitive treatment (Doppman JL: personal communication).

Corticotropin-independent Cushing’s syndrome is usually caused by an adrenal neoplasm. Benign tumors tend to be small (<5 cm in diameter) and secrete a single hormone, cortisol. The contralateral adrenal gland is suppressed by the cortisol secreted from the tumorous gland. If the value for Hounsfield units is less than 10 and the washout of contrast material is greater than 60% at 15 minutes, the tumor is almost certainly benign.33 Such tumors can be treated successfully with laparoscopic adrenalectomy.

The syndromes of micronodular and macronodular adrenal dysplasia usually affect both adrenal glands. The nodules secrete cortisol. Corticotropin is suppressed, as is the internodular tissue of the adrenal glands. Percutaneous bilateral adrenalectomy, followed by glucocorticoid and mineralocorticoid treatment, is curative.

Adrenal tumors secreting more than one hormone (i.e., cortisol and androgen or estrogen) are almost always malignant. Surgical removal of all detectable disease is indicated, as is a careful search for metastases. If metastases are found, they should be removed. This usually requires an open adrenalectomy. It goes without saying that adrenal tumors, nodules, and metastases should be treated by the most experienced endocrine cancer surgeon available.

If the plasma cortisol level on the morning after a transsphenoidal microadenomectomy is 0, the operation was a success. The patient should be treated with oral hydrocortisone, at a dose of 12 mg per square meter of body-surface area once a day in the morning, and a tetracosactide (Cortrosyn) stimulation test should be performed at 3-month intervals. When the tetracosactide-stimulated plasma cortisol level is higher than 20 μg per deciliter (551 μmol per liter), cortisol administration can be stopped. The same rule applies in the case of a unilateral adrenalectomy. If the adrenalectomy is bilateral, cortisol, at a dose of 12 to 15 mg per square meter per day, and fludrocortisone (Florinef), at a dose of 100 μg per day, should be prescribed as lifelong therapy.

SUMMARY

The obesity epidemic has led to necessary changes in the evaluation and treatment of patients with Cushing’s syndrome. The most dramatic change is the emphasis on the antianabolic alterations in Cushing’s syndrome, which can provide a strong basis for separating patients with Cushing’s syndrome from the more numerous patients with obesity and the metabolic syndrome. More can be done along these lines. Likelihood ratios are known for proximal muscle weakness and can be known for brain atrophy and growth failure in children.

The dexamethasone-suppression test, although still very popular, no longer has a role in the evaluation and treatment of patients with Cushing’s syndrome. Only three biochemical tests are needed: urinary free cortisol, plasma corticotropin, and plasma cortisol measurements. Urinary free cortisol excretion is the test that confirms the clinical diagnosis of Cushing’s syndrome. To be trustworthy, it must be performed in the most stringent way, with the use of high-pressure liquid chromatography followed by mass spectrometric quantitation of cortisol. Measurement of plasma corticotropin is used to separate corticotropin-dependent from corticotropin-independent causes of Cushing’s syndrome and to separate eutopic from ectopic secretion of corticotropin. Inferior petrosal sinus sampling should be performed in all patients with corticotropin-dependent Cushing’s syndrome because of the high prevalence of nonfunctioning incidental pituitary adenomas among such patients. Measurement of plasma cortisol has only one use: determining the success or failure of transsphenoidal microadenomectomy or adrenalectomy. If the plasma cortisol level is not measurable on the morning after the operation (<5 μg per deciliter [138 μmol per liter]), the procedure was a success; if it is measurable, the operation failed. The surgeon must not administer intraoperative or postoperative synthetic glucocorticoids until the plasma cortisol level has been measured.

Successful evaluation of a patient who is suspected of having Cushing’s syndrome requires an endocrinologist who is skilled in physical diagnosis. Also required is a laboratory that measures urinary free cortisol using high-performance liquid chromatography and mass spectrometry and that can measure plasma cortisol and plasma corticotropin by means of radioimmunoassay.

Inferior petrosal sinus sampling is performed by an interventional radiologist. The treatment for all causes of Cushing’s syndrome, other than exogenous glucocorticoids, is surgical, and neurosurgeons, endocrine surgeons, and cancer surgeons are needed. This level of multidisciplinary medical expertise is usually found only at academic medical centers. Thus, most, if not all, patients with Cushing’s syndrome should be referred to such a center for treatment.

Disclosure forms provided by the author are available with the full text of this article at NEJM.org.

No potential conflict of interest relevant to this article was reported.

SOURCE INFORMATION

From the Division of Endocrinology, Diabetes, and Clinical Nutrition, Oregon Health and Science University, Portland.

Address reprint requests to Dr. Loriaux at the Division of Endocrinology, Diabetes, and Clinical Nutrition, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd., L607, Portland, OR 97239-3098, or at .

From http://www.nejm.org/doi/full/10.1056/NEJMra1505550

Filed under: adrenal, Cushing, Cushing's, Helpful Doctors, pituitary | Tagged: , , , , , , , , , , , , , , , , , , , , , | Leave a comment »

Cushing’s Disease Treatment Market to Witness an Outstanding Growth by 2017 – 2025

Posted on March 2, 2017 by MaryO

Cushing disease is caused by tumour in the pituitary gland which leads to excessive secretion of a hormone called adrenocorticotrophic (ACTH), which in turn leads to increasing levels of cortisol in the body. Cortisol is a steroid hormone released by the adrenal glands and helps the body to deal with injury or infection. Increasing levels of cortisol increases the blood sugar and can even cause diabetes mellitus. However the disease is also caused due to excess production of hypothalamus corticotropin releasing hormone (CRH) which stimulates the synthesis of cortisol by the adrenal glands.

The condition is named after Harvey Cushing, the doctor who first identified the disease in 1912. Cushing disease results in Cushing syndrome. Cushing syndrome is a group of signs and symptoms developed due to prolonged exposure to cortisol.

Signs and symptoms of Cushing syndrome includes hypertension, abdominal obesity, muscle weakness, headache, fragile skin, acne, thin arms and legs, red stretch marks on stomach, fluid retention or swelling, excess body and facial hair, weight gain, acne, buffalo hump, tiredness, fatigue, brittle bones, low back pain, moon shaped face etc.

Symptoms vary from individual to individual depending upon the disease duration, age and gender of the patient.  Disease diagnosis is done by measuring levels of cortisol in patient’s urine, saliva or blood. For confirming the diagnosis, a blood test for ACTH is performed. The first-line treatment of the disease is through surgical resection of ACTH-secreting pituitary adenoma, however disease management is also done through medications, Cushing disease treatment market comprises of the drugs designed for lowering the level of cortisol in the body. Thus patients suffering from Cushing disease are prescribed medications such as ketoconazole, mitotane, aminoglutethimide metyrapone, mifepristone, etomidate and pasireotide.

Request to View Tables of Content @ http://www.persistencemarketresearch.com/toc/14155

Cushing’s disease treatment market revenue is growing with a stable growth rate, this is attributed to increasing number of pipeline drugs. Also increasing interest of pharmaceutical companies to develop Cushing disease drugs is a major factor contributing to the revenue growth of Cushing disease treatment market over the forecast period. Current and emerging players’ focuses on physician education and awareness regarding availability of different drugs for curing Cushing disease, thus increasing the referral speeds, time to diagnosis and volume of diagnosed Cushing disease individuals. Growing healthcare expenditure and increasing awareness regarding Cushing syndrome aids in the revenue growth of Cushing’s disease treatment market. Increasing number of new product launches also drives the market for Cushing’s disease Treatment devices. However availability of alternative therapies for curing Cushing syndrome is expected to hamper the growth of the Cushing’s disease treatment market over the forecast period.

The Cushing’s disease Treatment market is segment based on the product type, technology type and end user

Cushing’s disease Treatment market is segmented into following types:

By Drug Type

  • Ketoconazole
  • Mitotane
  • Aminoglutethimide
  • Metyrapone
  • Mifepristone
  • Etomidate
  • Pasireotide

By End User

  • Hospital Pharmacies
  • Retail Pharmacies
  • Drug Stores
  • Clinics
  • e-Commerce/Online Pharmacies

Cushing’s disease treatment market revenue is expected to grow at a good growth rate, over the forecast period. The market is anticipated to perform well in the near future due to increasing awareness regarding the condition. Also the market is anticipated to grow with a fastest CAGR over the forecast period, attributed to increasing investment in R&D and increasing number of new product launches which is estimated to drive the revenue growth of Cushing’s disease treatment market over the forecast period.

Depending on geographic region, the Cushing’s disease treatment market is segmented into five key regions: North America, Latin America, Europe, Asia Pacific (APAC) and Middle East & Africa (MEA).

North America is occupying the largest regional market share in the global Cushing’s disease treatment market owing to the presence of more number of market players, high awareness levels regarding Cushing syndrome. Healthcare expenditure and relatively larger number of R&D exercises pertaining to drug manufacturing and marketing activities in the region. Also Europe is expected to perform well in the near future due to increasing prevalence of the condition in the region.

Asia Pacific is expected to grow at the fastest CAGR because of increase in the number of people showing the symptoms of Cushing syndrome, thus boosting the market growth of Cushing’s disease treatment market throughout the forecast period.

Some players of Cushing’s disease Treatment market includes CORCEPT THERAPEUTICS, HRA Pharma, Strongbridge Biopharma plc, Novartis AG, etc. However there are numerous companies producing branded generics for Cushing disease. The companies in Cushing’s disease treatment market are increasingly engaged in strategic partnerships, collaborations and promotional activities to capture a greater pie of market share.

Buy Now: You can now buy a single user license of the report at http://www.persistencemarketresearch.com/checkout/14155

The final report customized as per your specific requirement will be sent to your e-mail id within 7-20 days, depending on the scope of the report.

The research report presents a comprehensive assessment of the market and contains thoughtful insights, facts, historical data, and statistically supported and industry-validated market data. It also contains projections using a suitable set of assumptions and methodologies. The research report provides analysis and information according to categories such as market segments, geographies, types, technology and applications.

For more information, please e-mail us at sales@persistencemarketresearch.com

About Us 

Persistence Market Research (PMR) is a U.S.-based full-service market intelligence firm specializing in syndicated research, custom research, and consulting services. PMR boasts market research expertise across the Healthcare, Chemicals and Materials, Technology and Media, Energy and Mining, Food and Beverages, Semiconductor and Electronics, Consumer Goods, and Shipping and Transportation industries. The company draws from its multi-disciplinary capabilities and high-pedigree team of analysts to share data that precisely corresponds to clients’ business needs.

PMR stands committed to bringing more accuracy and speed to clients’ business decisions. From ready-to-purchase market research reports to customized research solutions, PMR’s engagement models are highly flexible without compromising on its deep-seated research values.

Contact

Persistence Market Research Pvt. Ltd

305 Broadway

7th Floor, New York City,

NY 10007, United States,

USA – Canada Toll Free: 800-961-0353

Email: sales@persistencemarketresearch.com

 media@persistencemarketresearch.com

 Web: http://www.persistencemarketresearch.com

From http://www.medgadget.com/2017/03/cushings-disease-treatment-market-to-witness-an-outstanding-growth-by-2017-2025-persistence-market-research.html 

Filed under: Cushing's, pituitary, Treatments | Tagged: , , , , , , , , , , , , , , , , , , , , , , , , , , , | Leave a comment »

Next Page »
%d bloggers like this: