ACTH test after adenomectomy may accurately predict Cushing’s disease remission

Posted on August 24, 2018 by MaryO

A plasma adrenocorticotropic hormone suppression test performed shortly after surgical adenomectomy may accurately predict both short- and long-term remission of Cushing’s disease, according to research published in Pituitary.

“Cushing’s disease is caused by hypersecretion of adrenocorticotropic hormone (ACTH) by a pituitary adenoma, resulting in hypercortisolism,” Erik Uvelius, MD, of the department of clinical sciences, Skåne University Hospital, Lund University, Sweden, and colleagues wrote in the study background. “Surgical adenomectomy is the first line of treatment. Postoperative remission is reported in 43% to 95% of cases depending on factors such as adenoma size, finding of pituitary adenoma on preoperative MRI and surgeons’ experience. However, there is no consensus on what laboratory assays and biochemical thresholds should be used in determining or predicting remission over time.”

In the study, the researchers retrospectively gathered data from medical records of 28 patients who presented with Cushing’s disease to Skåne University Hospital between November 1998 and December 2011, undergoing 45 transsphenoidal adenomectomies.

On postoperative days 2 and 3, oral betamethasone was administered (1 mg at 8 a.m., 0.5 mg at 2 p.m., and 0.5 mg at 8 p.m.). Researchers assessed plasma cortisol and plasma ACTH before betamethasone administration and again at 24 and 48 hours, and measured 24-urinary free cortisol on postoperative day 3.

At 3 months postoperatively and then annually, plasma concentrations of morning cortisol and ACTH along with urinary-free cortisol and/or a low-dose dexamethasone suppression test were evaluated at the endocrinologists’ discretion. The researchers defined remission as lessening of clinical signs and symptoms of hypercortisolism, as well as laboratory confirmation through the various tests.

The researchers used Youden’s index to establish the cutoff with the highest sensitivity and specificity in predicting remission over the short term (3 months) and long term (5 years or more). Clinical accuracy of the different tests was illustrated through the area under curve.

The study population consisted of mainly women (71%), with a median age of 49.5 years. No significant disparities were seen in age, sex or surgical technique between patients who underwent a primary procedure and those who underwent reoperation. Two of the patients were diagnosed with pituitary carcinoma and 11 had a macroadenoma. ACTH positivity was identified in all adenomas and pathologists confirmed two cases of ACTH-producing carcinomas.

Of the 28 patients, 12 (43%) demonstrated long-term remission at last follow-up. Three patients were not deemed in remission after primary surgery but were not considered eligible for additional surgical intervention, whereas 13 patients underwent 17 reoperations to address remaining disease or recurrence. Four patients demonstrated long-term remission after a second or third procedure, equaling 16 patients (57%) achieving long-term remission, according to the researchers.

The researchers found that both short- and long-term remission were most effectively predicted through plasma cortisol after 24 and 48 hours with betamethasone. A short-term remission cutoff of 107 nmol/L was predicted with a sensitivity of 0.85, specificity of 0.94 and a positive predictive value of 0.96 and AUC of 0.92 (95% CI, 0.85-1). A long-term remission cutoff of 49 nmol/L was predicted with a sensitivity of 0.94, specificity of 0.93, positive predictive value of 0.88 and AUC of 0.98 (95% CI, 0.95-1). This cutoff was close to the suppression cutoff for the diagnosis of Cushing’s disease, 50 nmol/L. The cutoff of 25 nmol/L showed that the use of such a strict suppression cutoff would cause a low level of true positives and a higher occurrence of false negatives, according to the researchers.

“A 48 h 2 mg/day betamethasone suppression test day 2 and 3 after transsphenoidal surgery of Cushing’s disease could safely predict short- and long-term remission with high accuracy,” the researchers wrote. “Plasma cortisol after 24 hours of suppression showed the best accuracy in predicting 5 years’ remission. Until consensus on remission criteria, it is still the endocrinologists’ combined assessment that defines remission.” – by Jennifer Byrne

Disclosures: The authors report no relevant financial disclosures.

From https://www.healio.com/endocrinology/neuroendocrinology/news/in-the-journals/%7B0fdfb7b0-e418-4b53-b59d-1ffa3f7b8cd3%7D/acth-test-after-adenomectomy-may-accurately-predict-cushings-disease-remission

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

MEKT1 Could Be a Potential New Therapy for Treating Cushing’s Disease

Posted on August 2, 2018 by MaryO

MEKT1, a type of therapy called a PPAR-γ agonist, acts to reduce levels of the adrenocorticotropic hormone and could be a potential new therapy for Cushing’s disease, according to researchers.

Their study, “Inhibitory Effects of a Novel PPAR-γ Agonist MEKT1 on Pomc Expression/ACTH Secretion in AtT20 Cells,” was published in the journal PPAR Research.

Cushing’s disease is caused by a tumor in the pituitary gland — generally a type of tumor called an adenoma that produces high levels of adrenocorticotropic hormone (ACTH).

ACTH causes the adrenal glands to make too much cortisol, leading to the classic symptoms associated with Cushing’s disease.

PPAR-gamma (PPAR-γ) is a transcription factor protein (meaning it regulates the levels of certain genes by acting through other proteins), and is seen in high levels in the normal human pituitary and in ACTH-secreting pituitary adenomas.

The Pomc gene is a precursor molecule to ACTH. While it is known that PPAR-γ plays a role in regulating Pomc levels, its mechanism has not yet been clarified in pituitary cells.

PPAR-γ agonists — agents that activate PPAR-γ — include the medications rosiglitazone and pioglitazone, both of which are used to treat type 2 diabetes. Some studies have shown that rosiglitazone and pioglitazone have an effect on Pomc suppression, which would lead to lower levels of ACTH and help treat patients with Cushing’s disease.

However, the benefits of PPAR-γ agonists in the treatment of Cushing’s disease are still controversial.

Researchers examined the effects of a new PPAR-γ agonist, MEKT1, on Pomc levels and ACTH secretion using a mouse pituitary tumor-derived cell line called AtT20 cells. They also compared its effects with the well-established PPAR-γ agonists rosiglitazone and pioglitazone.

AtT20 cells were treated with either MEKT1, rosiglitazone, or pioglitazone at various concentrations ranging from 1 nM to 10 μM (micrometers) for 24 hours.

Results showed that 10 μM of MEKT1 significantly inhibited Pomc gene levels compared to rosiglitazone and pioglitazone. Additionally, ACTH secretion from AtT20 cells was also significantly inhibited by the agonist.

To see if it worked to decrease Pomc levels by acting specifically on PPAR-γ, researchers eliminated the PPAR-γ protein using a technique called siRNA knockdown. In this case, the effects of MEKT1 on Pomc levels were significantly halted.

It is known that other proteins, such as Nur77, Nurr1, and Tpit activate Pomc levels by binding to the promoter region of Pomc — the area of the gene responsible for activating gene levels.

To determine whether these proteins could be targeted by MEKT1, researchers also looked at levels of Nur77, Nurr1, and Tpit. The PPAR-γ agonist was found to significantly suppress the levels of the three genes that encode these proteins.

“Although clinical trials of MEKT1 are needed to determine its drug efficacy in the future, it can be speculated that MEKT1 is much more effective than the previously recognized PPAR-γ agonists rosiglitazone, and pioglitazone for the suppression of Pomc expression/ACTH secretion from our in vitro [laboratory] research,” they added.

Results from this study suggest MEKT1 could be a potential new therapy for the treatment of Cushing’s disease.

From https://cushingsdiseasenews.com/2018/06/12/mekt1-could-be-potential-therapy-treatment-cushings-disease/

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

Transsphenoidal Surgery Is Safe and Effective Treatment for Cushing’s Disease

Posted on July 28, 2018 by MaryO

Transsphenoidal surgery, a minimally invasive surgery to remove tumors in the pituitary gland, is safe and effective to treat Cushing’s disease, a 20-year history of cases in a Belgian hospital shows.

The surgery resulted in high remission rates (83%) in patients. It was also found to be safe, rarely leading to insufficient functioning of the pituitary gland.

The study, “Outcome of transsphenoidal surgery for Cushing’s Disease: a single-center experience over 20 years,” was published in the journal World Neurosurgery.

Surgical removal of tumors in the pituitary gland of the brain remains the gold standard for Cushing’s disease treatment.

Transsphenoidal surgery (TSS) usually leads to good remission rates ranging from 68-95%, depending on the location and type of tumor, the neurosurgeon’s expertise, follow-up period, and the definition of remission.

Today, TSS consists of surgery directed through the nose to get to the bottom of the skull, where the pituitary gland is located. The tumor is reached via the nasal cavity with no need for incisions on the face.

To address the safety and effectiveness of this type of surgery for treating Cushing’s, researchers retrospectively reviewed the outcome of 71 patients who received their first TSS at Saint-Luc Hospital, Belgium, between 1996 and 2017. Patients were followed for an average of 6.8 years (82 months).

Surgeons used a type of TSS that is image-guided with the help of a microscope which magnifies the surgeon’s vision.

Remission was defined as normal fasting cortisol level, normal 24-hour urinary-free cortisol, or prolonged need for hydrocortisone replacement for one year after surgery.

Replacement therapies are sometimes needed when the pituitary is not producing enough cortisol after surgery.

Patients were mostly women, ages 15 to 84. Some of them, 32%, required multiple surgeries.

In total, 46 patients out of 71 were in remission after the first surgery, 11 after the second surgery, one after the third, and one after the fourth intervention.

A successful first surgery, resulting in a one-year remission, was a positive indicator for patients, as it was associated with high final remission rates (95%).

However, if the first surgery failed, only 36% of patients achieved a final remission.

“Obtaining a lasting remission after a first TSS could be an interesting parameter to influence future therapeutic decisions [like] performing repeated surgery rather than choosing second-line therapies,” researchers wrote.

Overall, remission was achieved in 83% of patients who underwent a single or multiple TSS intervention, a recurrence rate comparable to previous reports.

Surgery was particularly successful for curing patients with macroadenomas — tumors larger than 10 mm — leading to a 92% remission rate.

Small tumors that were not visible on magnetic resonance imaging (MRI) scans were more difficult to treat, with only 71% of patients being cured. Still, such a remission rate was better than what is commonly reported for MRI-negative tumors. This is likely explained by a higher level of expertise by the surgeon.

Levels of cortisol one day after TSS were significantly lower in patients with long-term remission. However, high levels were still observed in a few patients, especially those who had Cushing’s disease for many years.

“Therefore, high cortisol levels in the postoperative early days do not always indicate persistent disease and later [cortisol] evaluation is warranted,” the researchers wrote.

Most complications from surgery were minor and transient, except for seven patients who developed diabetes. Only 8.8% of patients developed long-term failure of the pituitary gland, likely because physicians favored a less aggressive intervention plan to leave the pituitary gland as intact as possible.

However, such an approach may also explain why some patients had to undergo multiple surgeries to completely remove the tumor.

In addition, a longer duration of Cushing’s disease symptoms and higher cortisol levels before surgery could significantly predict a poorer likelihood of being cured by TSS.

“Neuronavigation-guided microscopic TSS is a safe and effective primary treatment for [Cushing’s disease], allowing high remission rates,” the researchers wrote.

From https://cushingsdiseasenews.com/2018/07/26/transsphenoidal-surgery-safe-effective-treatment-cushings-disease/

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

Medical therapy ‘reasonable option’ vs. surgery in Cushing’s disease

Posted on July 19, 2018 by MaryO

In a large percentage of patients with Cushing’s disease, medical therapy effectively induces cortisol normalization, suggesting the choice may serve as a useful first-line treatment vs. surgery for some, according to findings from a systematic review and meta-analysis published in Pituitary.

Cushing’s syndrome is generally approached by removal of the adrenocorticotropic hormone (ACTH)-producing tumor in ectopic disease and by adrenalectomy in ACTH-independent disease, Leonie H. A. Broersen, MD, of the department of medicine at Leiden University Medical Centre in Leiden, Netherlands, wrote in the study background. However, medical therapy can be used to control cortisol secretion preoperatively and as a “bridge” until control of hypercortisolism is achieved by radiotherapy, whereas use of medical therapy as a first-line treatment is increasing, they noted.

“Medical treatment is a reasonable treatment option for Cushing’s disease patients in case of a contraindication for surgery, a recurrence, or in patients choosing not to have surgery,” Broersen told Endocrine Today. “In case of side effects or no treatment effect, an alternate medical therapy or combination therapy can be considered.”

Broersen and colleagues analyzed data from 35 studies with 1,520 patients reporting on six medical therapies for Cushing’s disease, including studies assessing pasireotide (n = 2; Signifor LAR, Novartis), mitotane (n = 5; Lysodren, Bristol-Myers Squibb), cabergoline (n = 3), ketoconazole (n = 8), metyrapone (n = 5; Metopirone, HRA Pharma), mifepristone (n = 2; Korlym, Corcept Therapeutics) and multiple medical agents (n = 10), all published between 1971 and 2017. Studies included 11 single-arm trials, two randomized controlled trials with two treatment arms, and 22 cohort studies. In 28 studies, normalization of cortisol was measured by urinary free cortisol, midnight salivary cortisol or a low-dose dexamethasone test, with 25 studies reporting on clinical improvement and three studies reporting on quality of life.

Across studies, medical treatment was effective in normalizing cortisol levels in Cushing’s disease in 35.7% (cabergoline) to 81.8% (mitotane) of patients, according to the researchers. In seven studies reporting data separately for medical therapy as primary (n = 4) or secondary therapy (n = 5), researchers found medication as primary therapy normalized cortisol levels in 58.1% of patients (95% CI, 49.7-66.2), similar to the effect of medication as a secondary therapy (57.8%; 95% CI, 41.3-73.6). In studies in which at least 80% of patients with Cushing’s disease were pretreated with medication before surgery, researchers observed a preoperative normalization of cortisol levels in 32.3% of patients (95% CI, 20-45.8). Patients using medical monotherapy experienced a lower percentage of cortisol normalization vs. patients using multiple agents (49.4% vs. 65.7%), according to researchers, with normalization rates higher among patients with concurrent or previous radiotherapy.

Across studies, 39.9% of patients experienced mild adverse effects, and 15.2% experienced severe adverse effects.

“Importantly, medical agents for hypercortisolism can cause severe side effects, leading to therapy adjustment or withdrawal in 4.8% (cabergoline) to 28.4% (mitotane) of patients,” the researchers wrote. “These results suggest that medical therapy can be considered a reasonable treatment alternative to the first-choice surgical treatment when regarding treatment effectiveness and side effects.” – by Regina Schaffer

For more information: Leonie H. A. Broersen, MD, can be reached at l.h.aA.broersen@lumc.nl.

Disclosure: The authors report no relevant financial disclosures.

From https://www.healio.com/endocrinology/neuroendocrinology/news/in-the-journals/%7B294187ce-3f5e-4d3f-b02e-5023515c3b0b%7D/medical-therapy-reasonable-option-vs-surgery-in-cushings-disease

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

Cushing’s Syndrome Eludes Treatment Paradigm or Standard Approach to Care

Posted on July 7, 2018 by MaryO

Results of two systematic reviews indicate that while surgery is the preferred treatment, many patients present with contraindications without an accepted management paradigm leaving clinicians to follow a patient-centric approach to care.

Written by 

With commentary by Eliza B. Geer, MD

Cushing’s syndrome may arise from an endogenous glucocorticoid excess is either adrenocorticotropic hormone (ACTH)-dependent or ACTH-independent; each variation has numerous underlying causes, including pituitary tumor, adrenal tumor, or other unknown causes.

Although rare, ectopic Cushing’s syndrome results from a non-pituitary ACTH-producing source. Cushing’s disease, a type of Cushing’s syndrome, affects an estimated 1.2 to 2.4 million people each year, and is caused by an ACTH-secreting pituitary adenoma.1

While surgery is preferred for treatment of Cushing's syndrome many patients need a medical approach instead.

Gaining insights into treatment preferences and efficacy for Cushing’s syndrome were the focus of two separate systematic reviews and meta-analyses, both published in the journal, Pituitary: one regarding medical treatments for Cushing’s syndrome,2 and the other comparing endoscopic versus microscopic transsphenoidal surgery for Cushing’s disease.3

Assessing Medical Management of Cushing’s Syndrome

The meta-analysis examining medical care of individuals with Cushing’s syndrome encompassed 1520 total patients across 35 studies, most of whom had Cushing’s disease.2 However, only 2 of the 35 studies were randomized trials, highlighting the lack of and clear need for controlled clinical trials on medical therapies for Cushing’s syndrome.

Surgery is typically first-line treatment—whether transsphenoidal pituitary adenomectomy for Cushing’s disease,4 removal of the ACTH-producing tumor in ectopic Cushing’s syndrome or adrenalectomy in ACTH-independent Cushing’s syndrome.5

However, many patients require medical therapy owing to contraindications for surgery, for recurrent disease, or to control cortisol secretion prior to surgery or radiotherapy. Results of the meta-analysis reflected wide-ranging normalization of cortisol levels depending upon the agent used– from 35.7% for cabergoline to nearly 82% for mitotane in Cushing’s disease.2 Combination therapy (medications used either together or sequentially) was shown to increase effectiveness in normalizing cortisol levels.2

In an interview with EndocrineWeb, Eliza B. Geer, MD, medical director of the Multidisciplinary Pituitary and Skull Base Tumor Center at Memorial Sloan Kettering Cancer Center in New York City, noted that most medical therapies for Cushing’s syndrome are used off-label (in the US), and thus may lack clinical trial efficacy and safety data; consequently, this review provides useful information for treatment selection. However, Dr. Geer said there was substantial diversity of treatments reviewed in this paper – including tumor-directed therapies, cortisol synthesis inhibitors, an adrenolytic therapy, and a receptor blocker, used alone or in combination.

Further, treatments used in the studies addressed a range of Cushing’s etiologies and reflected heterogeneous study designs (for example follow-up ranged from 2 weeks to 11.5 years).2  As such, she said, “findings provided by this review should be viewed in the context of a broader clinical understanding of Cushing’s treatment.”

Specifically, Dr. Geer said, “Dr. Broersen’s analysis found that efficacy of medical therapy was improved by prior radiotherapy. But we know that radiotherapy is recommended on an individualized basis in only a fraction of Cushing’s patients, depending on tumor behavior and treatment history. Also, the fact that mitotane was shown here to have the highest efficacy of all therapies does not make this the appropriate treatment for all, or even most, Cushing’s patients; mitotane is adrenolytic and has a high rate of significant adverse effects.”

Too Many Questions Persist, Necessitating Focus on Attaining Management Paradigm

Dr. Geer also highlighted the need for answers to basic questions when investigating Cushing’s treatments: How do we define ‘successful’ treatment? What goals of care can patients expect? Which cortisol measurements and cut-offs can be used? How do we define clinical remission—resolution of which symptoms and comorbidities? She said Cushing’s syndrome is one of the most challenging endocrine diseases to treat because of the lack of an accepted, universal treatment or management paradigm.

“Treatment is often multimodal and always multidisciplinary, with patient-specific decision trees that must consider many factors, including goals of care, treatment history, disease etiology and severity, tumor behavior, and individual responses to medical therapies,” she told EndocrineWeb.

She concluded, “While Broersen et al’s study provides a useful review of available medical therapies, it reinforces something we already know about the treatment of Cushing’s: Expertise is required.”

Pituitary surgery is first-line treatment for Cushing’s disease. Currently, there are two main techniques for transsphenoidal pituitary surgery: microscopic and endoscopic. The operating microscope provides three-dimensional vision and may be advantageous in identifying small tumors; the broader field of vision afforded by the endoscope may be advantageous for complete resection of large tumors.3  Generally, despite an absence of studies directly comparing relative remission and complication rates between microscopic versus endoscopic approaches, most surgical centers choose to use one or the other; few have both.3

Examining the Surgical Options to Manage Cushing’s Disease

The second systematic review is the first to compare remission and recurrence rates, and mortality after microscopic versus endoscopic transsphenoidal pituitary surgery for Cushing’s disease.3 The review included 97 studies of 6695 patients: 5711 individuals having the microscopic procedure and 984 undergoing endoscopic surgery.

Results of the meta-analysis found no clear difference between the two techniques in overall remission (80%) or recurrence (10%).3 Short-term mortality for both techniques was < 0.5%. However, endoscopic surgery was associated with a greater occurrence of cerebrospinal fluid leak (12.9 vs 4.0%) but a lesser occurrence of transient diabetes insipidus (11.3 vs 21.7%).3

The authors reported a higher percentage of patients in remission (76.3 vs. 59.9%) and lower percentage recurrence rates (1.5 vs 17.0%) among patients undergoing endoscopic surgery for macroadenomas.3

When interviewed regarding the second meta-analysis,3 Dr. Geer said that the potential benefit of endoscopy over microscopy has been questioned for ACTH-secreting tumors specifically since most are microadenomas.

“With the caveat that few studies (four of the 97 reviewed) compared techniques directly, Broersen et al3 found that endoscopic surgery was associated with higher remission rates compared to microscopic surgery for large tumors, but the two techniques were comparable for small tumors,” said Dr. Geer, however, “one limitation of these data is the lack of standardized criteria to define diagnosis and remission of Cushing’s among the studies reviewed.”

Need for Consistency in Clinical Trials and Surgical Expertise

The study investigators concluded, “endoscopic surgery for patients with Cushing’s disease reaches comparable results for microadenomas, and probably better results for macroadenomas than microscopic surgery,” despite the greater learning curve associated with endoscopic surgery.3 As such, based on their findings, the authors concluded that “endoscopic surgery may thus be considered the current standard of care. Microscopic surgery can be used based on neurosurgeon’s preference.” They did not respond to EndocrineWeb for a request for comment.

As more neurosurgeons receiving training with the endoscope, the preferred technique for pituitary surgery is changing. Dr. Geer said, “Broersen’s review provides reassurance that the newer endoscopic technique is at least equal to the microscope for microadenomas and may be preferred for macroadenomas.”

“However, [conclusions based on the systematic review] do not change our role as endocrinologists treating Cushing’s disease, which is to refer, when indicated, to the available neurosurgeon with the most favorable outcomes and lowest rate of complications, both of which depend directly on level of experience with the procedure and the instrument being used, whether endoscope or microscope,” she said.

The authors had no financial conflicts to declare.

From https://www.endocrineweb.com/professional/cushings/cushings-syndrome-eludes-treatment-paradigm-standard-approach-care

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

Next Page »
%d bloggers like this: