New discoveries offer possible Cushing’s disease cure

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

Simultaneous Pituitary and Adrenal Adenomas in a Patient with Non ACTH Dependent Cushing Syndrome

Highlights

Cushing syndrome (CS) is a rare disorder with a variety of underlying etiologies.

CS is expected to affect 0.2 to 5 people per million per year.

Adrenal-dependent CS is an uncommon variant of CS.

This study reports a rare occurrence of pituitary and adrenal adenoma with CS.

Abstract

Introduction

Cushing syndrome is a rare disorder with a variety of underlying etiologies, that can be exogenous or endogenous (adrenocorticotropic hormone (ACTH)-dependent or ACTH-independent). The current study aims to report a case of ACTH-independent Cushing syndrome with adrenal adenoma and nonfunctioning pituitary adenoma.

Case report

A 37–year–old female presented with amenorrhea for the last year, associated with weight gain. She had a moon face, buffalo hump, and central obesity. A 24-hour urine collection for cortisol was performed, revealing elevated cortisol. Cortisol level was non-suppressed after administering dexamethasone. MRI of the pituitary revealed a pituitary microadenoma, and the CT scan of the abdomen with adrenal protocol revealed a left adrenal adenoma.

Discussion

Early diagnosis may be postponed due to the variety of clinical presentations and the referral of patients to different subspecialists based on their dominant symptoms (gynecological, dermatological, cardiovascular, psychiatric); it is, therefore, critical to consider the entire clinical presentation for correct diagnosis.

Conclusion

Due to the diversity in the presentation of CS, an accurate clinical, physical and endocrine examination is always recommended.

Keywords

Cushing syndrome
Cushing’s disease
Adrenal adenoma
Pituitary adenoma
Urine free cortisol

1. Introduction

Cushing syndrome (CS) is a collection of clinical manifestations caused by an excess of glucocorticoids [1]. CS is a rare disorder with a variety of underlying etiologies that can be exogenous due to continuous corticosteroid therapy for any underlying inflammatory illness or endogenous due to either adrenocorticotropic hormone (ACTH)-dependent or ACTH-independent [2][3]. Cushing syndrome is expected to affect 0.2 to 5 people per million per year. Around 10% of such cases involve children [4][5]. ACTH-dependent glucocorticoid excess owing to pituitary adenoma accounts for the majority (60–70%) of endogenous CS, with primary adrenal causes accounting for only 20–30% and ectopic ACTH-secreting tumors accounting for the remaining 5–10% [6]. Adrenal-dependent CS is an uncommon variant of CS caused mostly by benign (90%) or malignant (8%) adrenal tumors or, less frequently, bilateral micronodular (1%) or macronodular (1%) adrenal hyperplasia [7].

The current study aims to report a case of ACTH-independent Cushing syndrome with adrenal adenoma and nonfunctioning pituitary adenoma. The report has been arranged in line with SCARE guidelines and includes a brief literature review [8].

2. Case report

2.1. Patient’s information

A 37–year–old female presented with amenorrhea for the last year, associated with weight gain. She denied having polyuria, polydipsia, headaches, visual changes, dizziness, dryness of the skin, cold intolerance, or constipation. She had no history of chronic disease and denied using steroids. She visited an internist, a general surgeon, and a gynecologist and was treated for hypothyroidism. She was put on Thyroxin 100 μg daily, and oral contraceptive pills were given for her menstrual problems. Last time, the patient was referred to an endocrinology clinic, and they reviewed the clinical and physical examinations.

2.2. Clinical examination

She had a moon face, buffalo hump, central obesity, pink striae over her abdomen, and proximal weakness of the upper limbs. After reviewing the history and clinical examination, CS was suspected.

2.3. Diagnostic assessment

Because the thyroid function test revealed low thyroid-stimulating hormone (TSH), free T3, and freeT4, the patient was sent for a magnetic resonance imaging (MRI) of the pituitary, which revealed a pituitary microadenoma (7 ∗ 6 ∗ 5) mm (Fig. 1). Since the patient was taking thyroxin and oral contraceptive pills, the investigations were postponed for another six weeks due to the contraceptive pills’ influence on the results of the hormonal assessment for CS. After six weeks of no medication, a 24-hour urinary free cortisol (UFC) was performed three times, revealing elevated cortisol levels (1238, 1100, and 1248) nmol (normal range, 100–400) nmol. A dexamethasone suppression test was done (after administering dexamethasone tab 1 mg at 11 p.m., serum cortisol was measured at 9 a.m.). The morning serum cortisol level was 620 nmol (non-suppressed), which normally should be less than 50 nmol. The ACTH level was below 1 pg/mL.

Fig. 1

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Fig. 1. Contrast enhanced T1W weighted MRI (coronal section) showing small 7 mm hypo-enhanced microadenoma (yellow arrow) in right side of pituitary gland with mild superior bulge.

Based on these findings, ACTH independent CS was suspected. The computerized tomography (CT) scan of the abdomen with adrenal protocol revealed a left adrenal adenoma (33 mm × 25 mm) without features of malignancy (Fig. 2).

Fig. 2

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Fig. 2. Computed tomography scan of the abdomen with IV contrast, coronal section, showing 33 mm × 25 mm lobulated enhanced left adrenal tumor (yellow arrow), showing absolute washout on dynamic adrenal CT protocol, consistent with adrenal adenoma.

2.4. Therapeutic intervention

The patient was referred to the urologist clinic for left adrenalectomy after preparation for surgery and perioperative hormonal management. She underwent laparoscopic adrenalectomy and remained in the hospital for two days. The histopathology results supported the diagnosis of adrenal adenoma.

2.5. Follow-up

She was released home after two days on oral hydrocortisone 20 mg in the morning and 10 mg in the afternoon. After one month of follow-up, serum cortisol was 36 nmol, with the resolution of some features such as weight reduction (3 kg) and skin color (pink striae became white).

3. Discussion

Cushing’s syndrome is a serious and well-known medical condition that results from persistent exposure of the body to excessive glucocorticoids, either from endogenous or, most frequently, exogenous sources [9]. The average age of diagnosis is 41.4 years, with a female-to-male ratio of 3:1 [10]. ACTH-dependent CS accounts for almost 80% of endogenous CS, while ACTH-independent CS accounts for nearly 20% [10]. This potentially fatal condition is accompanied by several comorbidities, including hypertension, diabetes, coagulopathy, cardiovascular disease, infections, and fractures [11]. Exogenous CS, also known as iatrogenic CS, is more prevalent than endogenous CS and is caused by the injection of supraphysiologic glucocorticoid dosages [12]. ACTH-independent CS is induced by uncontrolled cortisol release from an adrenal gland lesion, most often an adenoma, adrenocortical cancer, or, in rare cases, ACTH-independent macronodular adrenal hyperplasia or primary pigmented nodular adrenal disease [13].

The majority of data suggests that early diagnosis is critical for reducing morbidity and mortality. Detection is based on clinical suspicion initially, followed by biochemical confirmation [14]. The clinical manifestation of CS varies depending on the severity and duration of glucocorticoid excess [14]. Some individuals may manifest varying symptoms and signs because of a rhythmic change in cortisol secretion, resulting in cyclical CS [15]. The classical symptoms of CS include weight gain, hirsutism, striae, plethora, hypertension, ecchymosis, lethargy, monthly irregularities, diminished libido, and proximal myopathy [16]. Neurobehavioral presentations include anxiety, sadness, mood swings, and memory loss [17]. Less commonly presented features include headaches, acne, edema, abdominal pain, backache, recurrent infection, female baldness, dorsal fat pad, frank diabetes, electrocardiographic abnormalities suggestive of cardiac hypertrophy, osteoporotic fractures, and cardiovascular disease from accelerated atherosclerosis [10]. The current case presented with amenorrhea, weight gain, moon face, buffalo hump, and skin discoloration of the abdomen.

Similar to the current case, early diagnosis may be postponed due to the variety of clinical presentations and the referral of patients to different subspecialists based on their dominant symptoms (gynecological, dermatological, cardiovascular, psychiatric); it is, therefore, critical to consider the entire clinical presentation for correct diagnosis [18]. Weight gain may be less apparent in children, but there is frequently an arrest in growth with a fall in height percentile and a delay in puberty [19].

The diagnosis and confirmation of the etiology can be difficult and time-consuming, requiring a variety of laboratory testing and imaging studies [20]. According to endocrine society guidelines, the initial assessment of CS must include one or more of the three following tests: 24-hour UFC measurement; evaluation of the diurnal variation of cortisol secretion by assessing the midnight serum or salivary cortisol level; and a low-dose dexamethasone suppression test, typically the 1 mg overnight test [21]. Although UFC has sufficient sensitivity and specificity, it does not function well in milder cases of Cushing’s syndrome [22]. In CS patients, the typical circadian rhythm of cortisol secretion is disrupted, and a high late-night cortisol serum level is the earliest and most sensitive diagnostic indicator of the condition [23]. In the current case, the UFC was elevated, and cortisol was unsuppressed after administration of dexamethasone.

All patients with CS should have a high-resolution pituitary MRI with a gadolinium-based contrast agent to prove the existence or absence of a pituitary lesion and to identify the source of ACTH between pituitary adenomas and ectopic lesions [24]. Adrenal CT scan is the imaging modality of choice for preoperatively localizing and subtyping adrenocortical lesions in ACTH-independent Cushing’s syndrome [9]. MRI of the pituitary gland of the current case showed a microadenoma and a CT scan of the adrenals showed left adrenal adenoma.

Surgical resection of the origin of the ACTH or glucocorticoid excess (pituitary adenoma, nonpituitary tumor-secreting ACTH, or adrenal tumor) is still the first-line treatment of all forms of CS because it leaves normal adjacent structures and results in prompt remission and inevitable recovery of regular adrenal function [12][25]. Laparoscopic (retroperitoneal or transperitoneal) adrenalectomy has become the gold standard technique for adrenal adenomas since it is associated with fewer postoperative morbidity, hospitalization, and expense when compared to open adrenalectomy [17]. In refractory cases, or when a patient is not a good candidate for surgery, cortisol-lowering medication may be employed [26]. The current case underwent left adrenalectomy.

Symptoms of CS, such as central obesity, muscular wasting or weakness, acne, hirsutism, and purple striae generally improve first and may subside gradually over a few months or even a year; nevertheless, these symptoms may remain in 10–30% of patients [27]. Glucocorticoid replacement is essential after adrenal-sparing curative surgery until the pituitary-adrenal function returns, which might take up to two years, especially if adrenal adenomas have been resected [25]. Chronic glucocorticoid excess causes lots of new co-morbidities, lowering the quality of life and increasing mortality. The most common causes of mortality in CS are cardiovascular disease and infections [28]. After one month of follow-up, serum cortisol was 36 nmol, and several features, such as weight loss (3 kg) and skin color, were resolved (pink striae became white).

In conclusion, the coexistence of adrenal adenoma and pituitary adenoma with CS is a rare possibility. Due to the diversity in the presentation of CS, an accurate clinical, physical and endocrine examination is always recommended. Laparoscopic adrenalectomy is the gold standard for treating adrenal adenoma.

Consent

Written informed consent was obtained from the patient’s family for publication of this case report and accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request.

Provenance and peer review

Not commissioned, externally peer-reviewed.

Ethical approval

Approval is not necessary for case report (till 3 cases in single report) in our locality.

The family gave consent for the publication of the report.

Funding

None.

Guarantor

Fahmi Hussein Kakamad, Fahmi.hussein@univsul.edu.iq.

Research registration number

Not applicable.

CRediT authorship contribution statement

Abdulwahid M. Salh: major contribution of the idea, literature review, final approval of the manuscript.

Rawa Bapir: Surgeon performing the operation, final approval of the manuscript.

Fahmi H. Kakamad: Writing the manuscript, literature review, final approval of the manuscript.

Soran H. Tahir, Fattah H. Fattah, Aras Gh. Mahmood, Rawezh Q. Salih, Shaho F. Ahmed: literature review, final approval of the manuscript.

Declaration of competing interest

None to be declared.

References

Rare Nasal Cancer May Have Caused Cushing’s Syndrome

A very rare case of Cushing’s syndrome developing as a result of a large and also rare cancer of the nasal sinuses gives insights into how to screen and treat such an anomaly, of which fewer than 25 cases have been reported in literature.

Paraneoplastic esthesioneuroblastoma (ENB), a very rare type of nasal tumor, may sometimes produce excess adrenocorticotrophic hormone (ACTH), leading to symptoms of Cushing’s syndrome, according to a recent case report that describes a case of ACTH-secreting ENB. The report aims to demonstrate the importance of recognizing its pathophysiology and treatment.

The case report, “A Case of Cushing’s Syndrome due to Ectopic Adrenocorticotropic Hormone Secretion from Esthesioneuroblastoma with Long Term Follow-Up after Resection,” was published in the journal Case Reports in Endocrinology.

It describes a 52-year-old Caucasian male who had a history of high blood pressure, severe weakness, abnormal production of urine, extreme thirstiness, and confusion.

He was scheduled to undergo surgery for a 7-centimeter skull base mass; the surgery was postponed due to severe high serum potassium concentrations and abnormally high pH levels. His plasma ACTH levels also were elevated and Cushing’s syndrome was suspected. Since imaging of the chest, abdomen, and pelvis did not show any ectopic (abnormal) sources of ACTH, the ENB was suspected to be the source.

Surgery was performed to remove the tumor, which was later found to be secreting ACTH. Consequently, following the procedure, his ACTH levels dropped to normal (below detection limit) and he did not need medication to normalize serum potassium levels. He then underwent subsequent chemoradiation and has shown no sign of recurrence 30 months after the operation, which is considered to be one of the longest follow-up periods for such a case.

Researchers declared it “a case of olfactory neuroblastoma with ectopic ACTH secretion that was treated with resection and adjuvant chemoradiation.”

“Given the paucity of this diagnosis, little is known about how best to treat these patients and how best to screen for complications such as adrenal insufficiency and follow-up,” they wrote. “Our case adds more data for better understanding of this disease.”

From https://cushingsdiseasenews.com/2018/04/03/rare-nasal-cancer-caused-cushings-syndrome-case-report-says/

Day 6, Cushing’s Awareness Challenge

In March of 1987, after the endo finally  confirmed that I had Cushing’s, I was sent to a local hospital where they repeated all those same tests for another week and decided that it was not my adrenal gland (Cushing’s Syndrome) creating the problem. The doctors and nurses had no idea what to do with me, so they put me on the brain cancer ward.

When I left this hospital after a week, we didn’t know any more than we had before.

As luck would have it, NIH (National Institutes of Health, Bethesda, Maryland) was doing a clinical trial of Cushing’s. I live in the same area as NIH so it was not too inconvenient but very scary at first to think of being tested there. At that time I only had a choice of NIH, Mayo Clinic and a place in Quebec to do this then-rare pituitary surgery called a Transsphenoidal Resection.

My husband asked my endo if it were his wife, if he would recommend this surgery.  The endo responded that he was divorcing his wife – he didn’t care what happened to her.  Oh, my!

I chose NIH – closest and free. After I was interviewed by the doctors there, I got a letter that I had been accepted into the clinical trial.

The night before I was admitted, I signed my will.  I was sure I was going to die there.  If not during testing, as a result of surgery.

The first time I was there was for 6 weeks as an inpatient. More of the same tests.

There were about 12 of us there and it was nice not to be alone with this mystery disease. Many of these Cushies (mostly women) were getting bald, couldn’t walk, having strokes, had diabetes. One was blind, one had a heart attack while I was there. Several were from Greece.

My first roommate was a nurse.  She spent the entire first night screaming in pain.  I was very glad when they moved me to a new room!

Towards the end of my testing period, I was looking forward to the surgery just to get this whole mess over with – either a cure or dying. While I was at NIH, I was gaining about a pound a day!

During the time I was home the weekend  before surgery, a college classmate of mine (I didn’t know her) DID die at NIH of a Cushing’s-related problem. I’m so glad I didn’t find out until reading the alumnae magazine a couple months later!  She was the same class, same major, same home-town, same disease…

We have a Scottish doctor named James Lind to thank for the clinical trial.  He  conducted the first ever clinical trial in 1747 and developed the theory that citrus fruits cured scurvy.  Lind  compared the effects of various different acidic substances, ranging from vinegar to cider, on groups of afflicted sailors, and found that the group who were given oranges and lemons had largely recovered from scurvy after 6 days.

I’d like to think that I advanced the knowledge of Cushing’s at least a little bit by being a guinea  pig in 1987-1989.

From the NIH: http://endocrine.niddk.nih.gov/pubs/cushings/cushings.aspx

Hope through Research

Several components of the National Institutes of Health (NIH) conduct and support research on Cushing’s syndrome and other disorders of the endocrine system, including the National Institute of Diabetes and Digestive and Kidney Diseases, the National Institute of Child Health and Human Development (NICHD), the National Institute of Neurological Disorders and Stroke, the National Cancer Institute, and the National Center for Research Resources.

NIH-supported scientists are conducting intensive research into the normal and abnormal function of the major endocrine glands and the many hormones of the endocrine system. Researchers continue to study the effects of excess cortisol, including its effect on brain structure and function. To refine the diagnostic process, studies are under way to assess the accuracy of existing screening tests and the effectiveness of new imaging techniques to evaluate patients with ectopic ACTH syndrome. Researchers are also investigating jugular vein sampling as a less invasive alternative to petrosal sinus sampling. Research into treatment options includes study of a new drug to treat the symptoms of Cushing’s syndrome caused by ectopic ACTH secretion.

Studies are under way to understand the causes of benign endocrine tumor formation, such as those that cause most cases of Cushing’s syndrome. In a few pituitary adenomas, specific gene defects have been identified and may provide important clues to understanding tumor formation. Endocrine factors may also play a role. Increasing evidence suggests that tumor formation is a multistep process. Understanding the basis of Cushing’s syndrome will yield new approaches to therapy.

The NIH supports research related to Cushing’s syndrome at medical centers throughout the United States. Scientists are also treating patients with Cushing’s syndrome at the NIH Clinical Center in Bethesda, MD. Physicians who are interested in referring an adult patient may contact Lynnette Nieman, M.D., at NICHD, 10 Center Drive, Room 1-3140, Bethesda, MD 20892-1109, or by phone at 301-496-8935. Physicians interested in referring a child or adolescent may contact Constantine Stratakis, M.D., D.Sc., at NICHD, 10 Center Drive, Room 1-3330, Bethesda, MD 20892-1103, or by phone at 301-402-1998.

BIPSS Diagnostic Method May Cause False Positive in Some Cases of Cyclic Cushing’s Syndrome

A diagnostic technique called bilateral inferior petrosal sinus sampling (BIPSS), which measures the levels of the adrenocorticotropic hormone (ACTH) produced by the pituitary gland, should only be used to diagnose cyclic Cushing’s syndrome patients during periods of cortisol excess, a case report shows.

When it is used during a spontaneous remission period of cycling Cushing’s syndrome, this kind of sampling can lead to false results, the researchers found.

The study, “A pitfall of bilateral inferior petrosal sinus sampling in cyclic Cushing’s syndrome,” was published in BMC Endocrine Disorders.

Cushing’s syndrome is caused by abnormally high levels of the hormone cortisol. This is most often the result of a tumor on the pituitary gland that produces too much ACTH, which tells the adrenal glands to increase cortisol secretion.

However, the disease may also occur due to adrenal tumors or tumors elsewhere in the body that also produce excess ACTH — referred to as ectopic Cushing’s syndrome.

Because treatment strategies differ, doctors need to determine the root cause of the condition before deciding which treatment to choose.

BIPSS can be useful in this regard. It is considered a gold standard diagnostic tool to determine whether ACTH is being produced and released by the pituitary gland or by an ectopic tumor.

However, in people with cycling Cushing’s syndrome, this technique might not be foolproof.

Researchers reported the case of a 43-year-old woman who had rapidly cycling Cushing’s syndrome, meaning she had periods of excess cortisol with Cushing’s syndrome symptoms — low potassium, high blood pressure, and weight gain — followed by normal cortisol levels where symptoms resolved spontaneously.

In general, the length of each period can vary anywhere from a few hours to several months; in the case of this woman, they alternated relatively rapidly — over the course of weeks.

After conducting a series of blood tests and physical exams, researchers suspected of Cushing’s syndrome caused by an ACTH-producing tumor.

The patient eventually was diagnosed with ectopic Cushing’s disease, but a BIPSS sampling performed during a spontaneous remission period led to an initial false diagnosis of pituitary Cushing’s. As a result, the woman underwent an unnecessary exploratory pituitary surgery that revealed no tumor on the pituitary.

Additional imaging studies then identified a few metastatic lesions, some of which were removed surgically, as the likely source of ACTH. However, the primary tumor still hasn’t been definitively identified. At the time of publication, the patient was still being treated for Cushing’s-related symptoms and receiving chemotherapy.

There is still a question of why the initial BIPSS result was a false positive. The researchers think that the likely explanation is that BIPSS was performed during an “off phase,” when cortisol levels were comparatively low. In fact, a later BIPSS performed during a period of high cortisol levels showed no evidence of ACTH excess in the pituitary.

This case “demonstrates the importance of performing diagnostic tests only during the phases of active cortisol secretion, as soon as first symptoms appear,” the researchers concluded.

From https://cushingsdiseasenews.com/2020/01/02/cushings-syndrome-case-study-shows-drawback-in-bipss-method/