A Case Series of Bilateral Inferior Petrosal Sinus Sampling Using Desmopressin for Evaluation of ACTH-Dependent Cushing’s Syndrome in Pediatric Patients

Posted on June 11, 2025 by MaryO

Abstract

Background

Pediatric Cushing Syndrome (CS) is rare and difficult to diagnose, especially when distinguishing ACTH-dependent subtypes. Bilateral inferior petrosal sinus sampling (BIPSS) is an essential but technically challenging procedure for this purpose. Because corticotropin-releasing hormone (CRH), the standard stimulant, has limitations, desmopressin is being explored as an alternative. This study assesses desmopressin-stimulated BIPSS for its diagnostic accuracy and tumor localization in pediatric CS within an Iranian cohort, addressing a gap in pediatric-specific diagnostic strategies and offering insights into the applicability of desmopressin in this context.

Methods

Four pediatric patients with inconclusive pituitary imaging and suspected Cushing’s disease (CD) underwent BIPSS with desmopressin at Taleghani Hospital, Tehran, Iran, between August 2015 and March 2019. Sensitivity of BIPSS for CD diagnosis was assessed, and tumor localization accuracy was evaluated during surgery.

Results

Bilateral IPSS demonstrated a sensitivity of 100% for diagnosing CD in pediatric patients. However, accuracy for tumor lateralization was moderate, with only 50% concordance between BIPSS lateralization and surgical findings. Specifically, two out of four patients had correct lateralization confirmed during surgery, while one patient with left lateralization was consistent with hypophysectomy findings. These discrepancies highlight challenges such as anatomical and drainage variations that can lead to mislocalization.

Conclusion

Desmopressin enhances the sensitivity of BIPSS for diagnosing pediatric CD, presenting as a viable alternative to CRH stimulation. Despite high sensitivity, caution is advised when interpreting BIPSS results for tumor localization. Further research is needed to optimize diagnostic strategies for pediatric CS management.

From https://link.springer.com/article/10.1007/s40200-025-01634-4

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PET/MRI may improve diagnosis of Cushing disease

Posted on April 5, 2024 by MaryO

PET/MRI could become the diagnostic method of choice over MRI alone for identifying small pituitary tumors associated with Cushing disease, according to a study published March 21 in the Journal of Nuclear Medicine.

In patients diagnosed with the disease yet who had inconclusive MRI results, PET/MRI was positive in 100% of cases, noted lead author Ilanah Pruis, a doctoral student at Erasmus University Medical Center in Rotterdam, Netherlands.

“This multimodal imaging technique provides a welcome improvement for diagnosis, planning of surgery, and clinical outcome in patients with Cushing disease,” the authors wrote.

Cushing disease is characterized by small tumors in pituitary glands, which causes them to secrete excess cortisol, the authors explained. While it is a rare disease, over time it can cause severely disabling conditions, such as high blood pressure or type II diabetes.

Currently, guidelines recommend the use of MRI and inferior petrosal sinus sampling (IPSS) to diagnose these tumors. IPSS is an invasive procedure in which cortisol hormone levels are sampled from the veins that drain the pituitary gland.

In up to 40% of patients, however, MRI is inconclusive, as the lesions are smaller than 10 millimeters in diameter. Even advanced MRI techniques, such as dynamic perfusion imaging, can leave small lesions undetected in up to one third of patients, the authors noted.

In preclinical work, PET imaging using a radiotracer named F-18 FET has been shown to bind with high affinity to a molecular target in pituitary tumors, and in this study, the researchers aimed to test this technique combined with MRI in a multimodal approach.

The researchers analyzed results from 22 patients (68% women; mean age 48 years) who underwent F-18 FET PET/MRI at Erasmus MC between February 2021 and December 2022. All patients showed a clear pituitary tumor F-18 FET-PET/MRI, whereas reading of the MRI alone yielded a suspected lesion in only 50%, the authors found.

T1-weighted postgadolinium MR images (A and C) and F-18 FET-PET/MR images (B and D) centered at pituitary before (A and B) and after (C and D) transsphenoidal surgery. This patient with Cushing disease showed clear focal uptake (B) but no clear lesion on previously obtained and accompanying MRI (A). Postoperative tissue analysis did confirm resection of small pituitary adenoma/PitNET, and postoperative F-18 FET-PET showed no residual uptake (D). Image courtesy of the Journal of Nuclear Medicine.T1-weighted postgadolinium MR images (A and C) and F-18 FET-PET/MR images (B and D) centered at pituitary before (A and B) and after (C and D) transsphenoidal surgery. This patient with Cushing disease showed clear focal uptake (B) but no clear lesion on previously obtained and accompanying MRI (A). Postoperative tissue analysis did confirm resection of small pituitary adenoma/PitNET, and postoperative F-18 FET-PET showed no residual uptake (D). Image courtesy of the Journal of Nuclear Medicine.

Importantly, 16 patients underwent treatment based on the results — either surgery, Gamma Knife, or CyberKnife therapy — with 12 of these patients achieving short-term remission, the authors noted.

“[F-18 FET-PET/MRI] is of great clinical value because it allows precision surgery and targeted Gamma Knife or CyberKnife therapy,” the group wrote.

The researchers noted that only one previous study evaluated F-18 FET-PET/MRI in these patients and that their study was limited, given the relatively small number of patients.

“Future studies will be directed at head-to-head comparisons of the performance of F-18 FET- PET and other diagnostic techniques, including advanced MRI sequences… preferably in patients at the time of initial clinical presentation,” the authors concluded.

A link to the full study can be found here.

From https://www.auntminnie.com/clinical-news/molecular-imaging/article/15667496/petmri-may-improve-diagnosis-of-cushing-disease

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Ectopic Cushing’s Syndrome From a Corticotropin-Releasing Hormone-Secreting Medullary Thyroid Carcinoma: a Rare Pitfall af Inferior Petrosal Sinus Sampling

Posted on October 27, 2023 by MaryO

Abstract

Summary

This case report describes a rare presentation of ectopic Cushing’s syndrome (CS) due to ectopic corticotropin-releasing hormone (CRH) production from a medullary thyroid carcinoma (MTC).

The patient, a 69-year-old man, presented with symptoms of muscle weakness, facial plethora, and easy bruising.

An inferior petrosal sinus sampling test (IPSS) demonstrated pituitary adrenocorticotrophic hormone (ACTH) secretion, but a whole-body somatostatin receptor scintigraphy (68Ga-DOTATOC PET/CT) revealed enhanced uptake in the right thyroid lobe which, in addition to a grossly elevated serum calcitonin level, was indicative of an MTC. A 18F-DOPA PET/CT scan supported the diagnosis, and histology confirmed the presence of MTC with perinodal growth and regional lymph node metastasis.

On immunohistochemical analysis, the tumor cell stained positively for calcitonin and CRH but negatively for ACTH. Distinctly elevated plasma CRH levels were documented. The patient therefore underwent thyroidectomy and bilateral adrenalectomy.

This case shows that CS caused by ectopic CRH secretion may masquerade as CS due to a false positive IPSS test. It also highlights the importance of considering rare causes of CS when diagnostic test results are ambiguous.

Learning points

  • Medullary thyroid carcinoma may secrete CRH and cause ectopic CS.
  • Ectopic CRH secretion entails a rare pitfall of inferior petrosal sinus sampling yielding a false positive test.
  • Plasma CRH measurements can be useful in selected cases.

Background

The common denominator of Cushing’s syndrome (CS) is autonomous hypersecretion of cortisol (1) and it is subdivided into ACTH-dependent and ACTH-independent causes. The majority of CS cases are ACTH-dependent (80–85%) with a pituitary corticotroph tumor as the most prevalent cause (Cushing’s disease), and less frequently an ectopic ACTH-producing tumor (2). The gold standard method to ascertain the source of ACTH secretion in CS patients is inferior petrosal sinus sampling (IPSS) with measurement of plasma ACTH levels in response to systemic corticotropin-releasing hormone (CRH) stimulation (3). The IPSS has a very high sensitivity and specificity of 88–100% and 67–100%, respectively (4), but pitfalls do exist, including the rare ectopic CRH-producing tumor, which may yield a false positive test result (3). Here, we describe a very rare case masquerading as CS including a positive IPSS test.

Case presentation

A 69-year-old man presented at a local hospital with a 6-month history of progressive fatigue, muscle weakness and wasting, easy bruising, facial plethora, and fluid retention. His serum potassium level was 2.6 mmol/L (reference range: 3.5–4.2 mmol/L) without a history of diuretics use. His previous medical history included spinal stenosis, benign prostatic hyperplasia, and hypertension. An electromyography showed no sign of polyneuropathy and an echocardiography showed no signs of heart failure with an ejection fraction of 55%. MRI of the spine revealed multiple compression fractures, and the patient underwent spinal fusion and decompression surgery; during this admission he was diagnosed with type 2 diabetes (HbA1c: 55 mmol/mol). After spine surgery, the patient developed a pulmonary embolism and initiated treatment with rivaroxaban.

Establishing the diagnosis of ACTH-dependent CS

Six months after his spine surgery, the patient was referred to the regional department of endocrinology for osteoporosis management. Blood tests revealed a low serum testosterone level with non-elevated luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels (Table 1). An overnight 1 mg dexamethasone suppression test was positive with a morning cortisol level of 254 nmol/L and three consecutive 24-h urinary cortisol levels were markedly elevated with mean level of ≈600 nmol/24 h (reference range: 12–150 nmol/24 h). A single plasma ACTH was 37 ng/L (Table 1).

Table 1Baseline endocrine assessment.

Parameters Patient’s values Reference range
ACTH, ng/L 37 7–64
UFC, nmol/day 588 12–150
Urinary cortisol, nmol/L 600 171–536
OD, nmol/L 254 <50
Free testosterone, nmol/L 0.061 0.17–0.59
HbA1c, mmol/mol 55 <48
FSH, IU/L 7.4 1.2–15.8
LH, IU/L 2.2 1.7–8.6

ACTH, adrenocorticotropin; FSH, follicle-stimulating hormone; IU, international units; LH, luteinizing hormone; OD, plasma cortisol levels after a 1 mg overnight dexamethasone suppression test; UFC, urine free cortisol hormone.

Differential diagnostic tests

The patient was referred to a tertiary center for further examinations. Ketoconazole treatment was started to alleviate the consequences of hypercortisolism. A pituitary MRI revealed an intrasellar microtumor with a maximal diameter of 6 mm and an IPSS was ordered. A whole-body somatostatin receptor scintigraphy (68Ga-DOTATOC PET/CT) was also performed to evaluate the presence of a potential neuroendocrine tumor. This revealed multiple areas of enhanced uptake including the right thyroid lobe and cervical lymph nodes in the neck (with CT correlates), as well as in the duodenum (with no CT correlate). Concomitantly, a grossly elevated serum calcitonin level of 528 pmol/L (reference range <2.79 pmol/L) was measured.

Subsequently, the IPSS revealed pituitary ACTH secretion with a central-to-peripheral ACTH ratio >3 (Table 2). The right petrosal sinus was not successfully catheterized; thus, lateralization could not be determined.

To corroborate the diagnosis MTC, a 18F-DOPA PET/CT scan (FDOPA) was performed (5), which showed pathologically enhanced uptake in the right thyroid lobe and regional lymph nodes (Fig. 1). An ultrasound-guided core needle biopsy from the thyroid nodule was inconclusive; however, the patient underwent total thyroidectomy and regional lymph node resection, from which histology confirmed the diagnosis of disseminated MTC. Standard replacement with levothyroxine, calcium, and vitamin D was initiated. A blood sample was collected, and genomic DNA was extracted. The DNA analysis for RET germline mutation was negative.

Figure 1View Full Size
Figure 1
18F-DOPA PET/CT scan with pathologically enhanced uptake in the right thyroid lobe (large blue arrow on the left side) and regional lymph nodes (small blue arrows).

Citation: Endocrinology, Diabetes & Metabolism Case Reports 2023, 3; 10.1530/EDM-23-0057

Table 2Results from the inferior petrosal sinus sampling.*

Time (min) Left IPSS Peripheral L/P
-5 42 36 1.2
-1 116 33 3.5
2 120 32 3.8
5 209 28 7.5
7 180 43 4.2
10 529 34 15.6
15 431 37 11.6

*Data represents ACTH levels in ng/L. IPSS Inferior petrosal sampling ACTH Adrenocorticotropin hormone CRH Corticotropin-releasing hormone, L/P Ratio of left (L) inferior petrosal sinus to peripheral venous ACTH concentrations.

Pathology

Total thyroidectomy and bilateral cervical lymph node dissection (level six and seven) were performed. Macroscopic evaluation of the right thyroid lobe revealed a 24 mm, irregular solid yellow tumor. Microscopically the tumor showed an infiltrating architecture with pseudofollicles and confluent solid areas. Calcification was prominent, but no amyloid deposition was seen. The tumor cells were pleomorphic with irregular nuclei and heterogenic chromatin structure. No mitotic activity or necrosis was observed. On immunohistochemical analysis, the tumor cells expressed thyroid transcription factor 1 and stained strongly for carcinoembryonic antigen and calcitonin; tumor cells were focally positive for cytokeratin 19. The tumor was completely negative for ACTH, thyroid peroxidase, and the Hector Battifora mesothelial-1 antigen. Further analysis revealed positive immunostaining for CRH (Fig. 2). The Ki-67 index was very low (0–1%), indicating a low cellular proliferation. Molecular testing for somatic RET mutation was not performed.

Figure 2View Full Size
Figure 2
Histopathological findings and immunohistochemical studies of MTC. (A) Microscopic features of medullary thyroid carcinoma. (B) Polygonal tumor cells (hematoxylin and eosin, ×40). (C) Tumor cells stain for calcitonin (×20). (D) Immunohistochemical stain (×400) for CRH showing cells being positive (brown). (E) Pituitary tissue from healthy control staining positive for ACTH in comparison to (F) ACTH-negative cells MTC tissue from the patient (×20).

Citation: Endocrinology, Diabetes & Metabolism Case Reports 2023, 3; 10.1530/EDM-23-0057

No malignancy was found in the left thyroid lobe and there was no evidence of C-cell hyperplasia. Regional lymph node metastasis was found in 13 out of 15 nodes with extranodal extension.

Outcome and follow-up

Follow-up

Serum calcitonin levels declined after neck surgery but remained grossly elevated (118 pmol/L 3 weeks post surgery) and cortisol levels remained high. Ketoconazole treatment was poorly tolerated and not sufficiently effective. Plasma levels of CRH were measured by a competitive-ELISA kit (EKX-KIZI6R-96 Nordic BioSite), according to the instructions provided by the manufacturer. The intra- and interassay %CV (coefficient of variability) were below 8% and 10%, respectively, and the assay sensitivity was 1.4 pg/mL. The plasma CRH was distinctly elevated compared to in-house healthy controls both before and after thyroid surgery (Fig. 3).

Figure 3View Full Size
Figure 3
Plasma CRH levels before and after total thyroidectomy compared to three healthy controls.

Citation: Endocrinology, Diabetes & Metabolism Case Reports 2023, 3; 10.1530/EDM-23-0057

The patient subsequently underwent uneventful bilateral laparoscopic adrenalectomy followed by standard replacement therapy with hydrocortisone and fludrocortisone. The symptoms and signs of his CS gradually subsided. Pathology revealed bilateral cortical hyperplasia as expected.

The patient continues follow-up at the Department of Oncology and the Department of Endocrinology and Internal Medicine. At 13-month follow-up, 68Ga-DOTATOC shows residual disease with pathologically enhanced uptake in two lymph nodes, whereas the previously described focal DOTATOC uptake in the duodenum was less pronounced (still no CT correlate). Serum calcitonin was 93 pmol/L at the 13-month follow-up.

Discussion

Diagnostic challenges remain in the distinction between pituitary and ectopic ACTH-dependent CS, and several diagnostic tools are used in combination, none of which is infallible, including IPSS (6). Our case and others illustrate that ectopic CRH secretion may yield a false positive IPSS test result (3). Measurement of circulating CRH levels is relevant if an ectopic CRH producing tumor is suspected, but the assay is not routinely available in clinical practice (Lynnette K Nieman M. Measurement of ACTH, CRH, and other hypothalamic and pituitary peptides https://www.uptodate.com/contents/measurement-of-acth-crh-and-other-hypothalamic-and-pituitary-peptides: UpToDate; 2019). In our case, the presence of elevated plasma CRH levels after thyroidectomy strengthened the indication for bilateral adrenalectomy.

The most common neoplasm causing ectopic CS is small-cell lung cancer, whereas MTC accounts for 2–8% of ectopic cases (7). The development of CS in relation to MTC is generally associated with advanced disease and poor prognosis of an otherwise relatively indolent cancer (8), and the clinical progression of CS is usually rapid, why an early recognition and rapid control of hypercortisolemia and MTC is necessary to decrease morbidity and mortality (7, 9). Our case does have residual disease; however, he remains progression-free with stable and relatively low calcitonin levels within 1-year follow-up.

Only a very limited number of cases of ectopic tumors with either combined ACTH and CRH secretion or isolated CRH secretion have been reported, with ectopic CRH secretion accounting for less than 1% of CS (9).

An ACTH- or CRH-producing tumor can be difficult to localize and may include gastric ACTH/CRH-secreting neuroendocrine tumors (9). In our case, the 68Ga-DOTATOC identified a possible duodenal site, in addition to the MTC, but an upper gastrointestinal endoscopy revealed no pathological findings and there was no CT correlate. Thus, we concluded that the most likely and sole source of ectopic CRH was the MTC and its metastases.

To our knowledge, no official guidelines for managing ectopic ACTH-dependent CS have been established. In a recent publication by Alba et al. (10), the authors demonstrated a clinical algorithm (The Mount Sinai Clinical Pathway, MSCP) and recommendation for the management of CS due to ectopic ACTH secretion.

Essentially, our approach in this particular case followed these recommendations, including source location by CT and 68Ga-DOTATATE PET/CT imaging, acute management with ketoconazole, and finally, bilateral adrenalectomy as curative MTC surgery was not possible. In retrospect, performance of the IPSS could be questioned in view of the MTC diagnosis. In real time, however, a pituitary MRI performed early in the diagnostic process revealed a microadenoma, which prompted the IPSS. In parallel, a somatostatin receptor scintigraphy (68Ga-DOTATOC PET/CT) was also done, which raised the suspicion of an MTC.

Conclusion

We report a very rare case of an ectopic CS caused by a CRH-secreting MTC. Although IPSS has stood the test of time in the differential diagnosis of ACTH-dependent CS, this case illustrates a rare pitfall.

Declaration of interest

The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.

Funding

This research did not receive any specific grant from any funding agency in the public, commercial, or not-for-profit sector.

Patient consent

Written informed consent for publication of their clinical details was obtained from the patient.

Author contribution statement

JOJ and MJO are the physicians responsible for the patient. LR performed the thyroidectomy and bilateral adrenalectomy. SHM and SLA assessed and reassessed the histopathology and the immunohistochemical analysis. MB measured plasma CRH. VM, JOJ, and MJO drafted the manuscript. All authors contributed to critical revision of the manuscript.

References

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Minimally Invasive Approaches Lead to High Remission Rates in Children

Posted on September 5, 2018 by MaryO

Minimally invasive diagnostic methods and transnasal surgery may lead to remission in nearly all children with Cushing’s disease, while avoiding more aggressive approaches such as radiation or removal of the adrenal glands, a study shows.

The study, “A personal series of 100 children operated for Cushing’s disease (CD): optimizing minimally invasive diagnosis and transnasal surgery to achieve nearly 100% remission including reoperations,” was published in the Journal of Pediatric Endocrinology and Metabolism.

Normally, the pituitary produces adrenocorticotropic hormone (ACTH), which stimulates the adrenal glands to produce cortisol. When a patient has a pituitary tumor, that indirectly leads to high levels of cortisol, leading to development of Cushing’s disease (CD).

In transnasal surgery (TNS), a surgeon goes through the nose using an endoscope to remove a pituitary tumor. The approach is the first-choice treatment for children with Cushing’s disease due to ACTH-secreting adenomas — or tumors — in the pituitary gland.

Micro-adenomas, defined as less than 4 mm, are more common in children and need surgical expertise for removal. It is necessary to determine the exact location of the tumor before conducting the surgery.

Additionally, many surgeons perform radiotherapy or bilateral adrenalectomy (removal of both adrenal glands) after the surgery. However, these options are not ideal as they can be detrimental to children who need to re-establish normal growth and development patterns.

Dieter K. Lüdecke, a surgeon from Germany’s University of Hamburg, has been able to achieve nearly 100% remission while minimizing the need for pituitary radiation or bilateral adrenalectomy. In this study, researchers looked at how these high remission rates can be achieved while minimizing radiotherapy or bilateral adrenalectomy.

Researchers analyzed 100 patients with pediatric CD who had been referred to Lüdecke for surgery from 1980-2009. Data was published in two separate series — series 1, which covers patients from 1980-1995, and series 2, which covers 1996-2009. All the surgeries employed direct TNS.

Diagnostic methods for CD have improved significantly over the past 30 years. Advanced endocrine diagnostic investigations, such as testing for levels of salivary cortisol in the late evening and cortisol-releasing hormone tests, have made a diagnosis of CD less invasive. This is particularly important for excluding children with obesity alone from children with obesity and CD. Methods to determine the precise location of micro-adenomas have also improved.

The initial methodology to localize tumors was known as inferior petrosal sinus sampling (IPSS), an invasive procedure in which ACTH levels are sampled from the veins that drain the pituitary gland.

In series 1, IPSS was performed in 24% of patients, among which 46% were found to have the wrong tumor location. Therefore, IPSS was deemed invasive, risky, and unreliable for this purpose.

All adenomas were removed with extensive pituitary exploration. Two patients in series 1 underwent early repeat surgery; all were successful.

Lüdecke introduced intraoperative cavernous sinus sampling (CSS), an improved way to predict location of adenomas. This was found to be very helpful in highly select cases and could also be done preoperatively for very small adenomas.

In series 2, CSS was used in only 15% of patients thanks to improved MRI and endocrinology tests. All patients who underwent CSS had correct localization of their tumors, indicating its superiority over IPSS.

In series 2, three patients underwent repeat TNS, which was successful. In these recurrences, TNS minimized the need for irradiation. The side effects of TNS were minimal. Recurrence rate in series 1 was 16% and 11% in series 2.

While Lüdecke’s patients achieved a remission rate of 98%, other studies show cure rates of 45-69%. Only 4% of patients in these two series received radiation therapy.

“Minimally invasive unilateral, microsurgical TNS is important functionally for both the nose and pituitary,” the researchers concluded. “Including early re-operations, a 98% remission rate could be achieved and the high risk of pituitary function loss with radiotherapy could be avoided.”

From https://cushingsdiseasenews.com/2018/09/04/minimally-invasive-methods-yield-high-remission-in-cushings-disease-children/

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New ACTH Detection Method Improves Cure Rates in Cushing’s Disease Patients

Posted on October 20, 2017 by MaryO

Researchers have identified a new, quick method for detecting ACTH-producing tumors – called Elecsys – that can improve the cure rates of Cushing’s disease patients undergoing surgery.

The study, “Long-term outcomes of tissue-based ACTH-antibody assay–guided transsphenoidal resection of pituitary adenomas in Cushing disease,” was published in the Journal of Neurosurgery.

Transsphenoidal resection (TSR) – a surgical procedure performed through the nose and sphenoid sinus to remove a pituitary tumor – has been the method of choice for treatment for Cushing’s disease.

However, it often fails to localize the tumor with precision, leading to an incomplete resection (removal). This is likely a result of the preoperative methods used to guide surgeons before surgery, which include both magnetic resonance imaging (MRI) and a minimally invasive procedure called bilateral inferior petrosal sinus sampling (BIPSS) that measures ACTH in the veins that drain the pituitary gland.

However, both “suffer from suboptimal sensitivity and thus allow for incomplete resections, specially if pathological frozen sections fail to identify tumor,” researchers wrote.

MRI, for example, detects only 50 percent of Cushing’s adenomas, limiting surgeons’ ability to conduct curative TSR surgeries. Therefore, better diagnostic and tumor localization techniques are needed to increase the likelihood that initial surgeries can remove the entire tumor and cure patients.

A team of researchers at Yale School of Medicine evaluated a new method for guiding tumor localization during TSR. The method – a double-antibody sandwich assay for ACTH – is performed in the operating room in resected pituitary samples from patients. ACTH (adrenocorticotropic hormone) is a hormone produced in the pituitary gland in the brain, that simulated cortisol production in the adrenal glands. In patients with Cushing disease the pituitary gland releases too much ACTH.

In the new method – called Elecsys – samples are squeezed between sandwich-like system composed of two antibodies that recognize two sections of the ACTH protein. The three-step procedure is quick, allowing doctors to analyze samples in the operating room and determine if they have removed the entire tumors.

The performance and outcomes associated with the Elecsys were assessed by reviewing data of tissue samples from 14 patients with ACTH-secreting adenomas, who underwent TSR surgeries between 2009 and 2014.

“The intraoperative TSR protocol was modified with the introduction of the ACTH assay such that if either the assay or the frozen-section pathology returned results positive for tumor, that area of the gland was resected,” the researchers explained.

The new ACTH method detected tumor tissue and was capable of distinguishing it from normal tissue with a 95% sensitivity and 71.3% specificity. These values are comparable to those using the standard method for tumor localization, which requires frozen sections of the tumor. This suggests that the test can be used either in conjunction with or in place of frozen sections.

Also, 85.7% of the patients achieved long-term disease remission, with the remission rate exceeding the rate with previous methods (71.9%).

Overall, “these preliminary findings reflect the promising potential of tissue-based ACTH-antibody-guided assay for improving the cure rates of Cushing’s disease patients undergoing TSR. Further studies with larger sample sizes, further refinements of assay interpretation, and longer-term follow-ups are needed,” the study concluded.

From https://cushingsdiseasenews.com/2017/10/19/acth-detection-method-improved-cure-rates-cushings-disease-study-shows/

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