Desmopressin is Promising Alternative in Diagnosing Cushing’s Disease

Bilateral inferior petrosal sinus sampling (IPSS) — a procedure that uses desmopressin to determine levels of ACTH hormone from veins that drain from the pituitary gland, is a sensitive way to diagnose patients with Cushing’s disease and find tumors, a Chinese study shows.

The study, “Tumour Lateralization in Cushing’s disease by Inferior Petrosal Sinus Sampling with desmopressin,” appeared in the journal Clinical Endocrinology.

Cushing’s disease is characterized by excessive production of the adrenocorticotropin hormone (ACTH) caused by a tumor in the pituitary gland. ACTH is the hormone that causes the adrenal glands to produce cortisol.

Currently, pituitary imaging is insufficient to confirm a Cushing’s diagnosis. This is because 70 percent of pituitary adenomas in Cushing’s are microadenomas, which are physically very small. As a result, 40 percent of Cushing’s patients are reported as being healthy.

This means that a Cushing’s diagnosis requires a combination of techniques including clinical symptoms, imaging methods and endocrinological assays that include measures of serum cortisol and ACTH levels.

IPSS determines ACTH levels from veins that drain from the pituitary gland. ACTH levels are then compared to ACTH levels in blood. Higher levels in the pituitary gland indicate a pituitary tumor.

IPSS can also be used to determine tumor lateralization, which refers to which side of the pituitary gland the tumor is located on. The test is 69 percent accurate.

Doctors administer IPSS along with corticotropin-releasing hormone (CRH) stimulation. IPSS with CRH is considered the gold standard for preoperative diagnosis of Cushing’s, with a diagnostic sensitivity (or true positive rate) of 95 percent and specificity (or true negative rate) of 90 to 95 percent. Unfortunately, the high cost and limited availability of CRH make it impractical for many patients.

Desmopressin has been used to replace CRH to stimulate ACTH secretion for IPSS, and prior studies have shown that desmopressin’s sensitivity is comparable to that of CRH.

Researchers at Peking Union Medical College in Beijing conducted a retrospective analysis of their experience using desmopressin-stimulated IPSS to determine its diagnostic value for Cushing’s and its predictive value for tumor lateralization.

Researchers analyzed 91 Cushing’s patients who either had negative findings on the MRI imaging of the pituitary or negative high-dose dexamethasone suppression tests, which is another method of evaluation. All patients underwent IPSS with desmopressin, followed by pituitary surgery to extract the tumor.

Of the 91 patients tested, 90 patients had confirmed Cushing’s. And of these, 89 had positive IPSS findings, which led to a sensitivity of 98.9 percent for this test. One patient out of 91 who did not have Cushing’s also underwent this test, which led to a negative IPSS result and a specificity of 100 percent.

Researchers also determined tumor lateralization in patients who were ultimately diagnosed with Cushing’s and underwent surgery. Results of the IPSS showed a 72.5 percent concordance between the results from the IPSS and the surgery.

Therefore, IPSS with desmopressin is a comparable approach to IPSS with CRH for the diagnosis of Cushing’s. It also demonstrates moderate accuracy in determining the location of tumors.

“Like many medical centers in China, we currently have no supply of CRH, while desmopressin is readily available,” researchers concluded. “Moreover, desmopressin is cheaper than CRH. As our data and other studies indicate, IPSS with desmopressin yielded comparable outcomes to IPSS with CRH. Therefore, desmopressin-stimulated IPSS might serve as a possible alternative to CRH-stimulated IPSS.”


Long-acting Signifor Has Similar Safety Profiles as Twice-daily Treatment in Cushing’s Patients, Trial Showed

A long-acting, once-a-month treatment of Signifor (pasireotide) normalized cortisol levels in 40% of patients with Cushing’s disease whose disease had recurred after surgery, or who were not candidates for surgery, according to new data from a Phase 3 trial.

The safety profiles of the once-monthly regimen proved to be similar to standard twice-daily Signifor treatments, researchers found.

The study, “Efficacy and safety of once-monthly pasireotide in Cushing’s disease: a 12 month clinical trial,” was published in the journal The Lancet Diabetes & Endocrinology.

Novartis‘ Signifor in its twice-daily injection formulation has already been approved for treating Cushing’s in the U.S. and elsewhere.

The 12-month, Phase 3 trial (NCT01374906) was conducted at 57 sites in 19 countries. The study included 150 patients with Cushing’s whose cortisol levels had risen or not dropped at all after surgery, or who were unable to undergo surgery.

Between Dec. 28, 2011, and Dec. 9, 2014, participants were randomized to receive either 10 mg or 30 mg of Signifor every four weeks, via an injection to the muscle. If, after four months of therapy, cortisol urinary levels (mUFC) were 50% greater than the upper normal limit, the dose could be increased from 10 mg to 30 mg, or from 30 mg to 40 mg. It could also be increased after seven, nine, or 12 months if the mUFC concentration was greater than normal.

The goal was to normalize average concentrations of free cortisol in the urine to less than or equal to the upper normal limit at month seven. It was met by 31 of the 74 patients in the 10 mg group (41.9%) and 31 of the 76 patients in the 30 mg group (40.8%).

The most common adverse events were hyperglycemia (high concentration of blood sugar), diarrhea, cholelithiasis (gall stones), diabetes, and nausea.

The researchers consider this treatment to be a good option for patients whose disease has returned after surgery, or who cannot undergo surgery. The long-lasting treatment schedule of one injection per month is more convenient for patients than the twice-daily subcutaneous injection, making it more likely that they would not discontinue treatment.

“Surgical resection of the causative pituitary adenoma is the first-line treatment of choice for most patients with Cushing’s disease, which leads to remission in greater than 75% of patients if done by an expert pituitary surgeon,” wrote Dr. Andre Lacroix, MD, a professor in the Department of Medicine at the University of Montreal teaching hospital, and colleagues.

“However, surgery is not always successful, and disease recurrence can occur several years after initial remission, while some patients refuse or are not candidates for surgery. As a result, many patients require additional treatment options.”

“Long-acting pasireotide normalized mUFC concentration in about 40% of patients with Cushing’s disease at month 7 and had a similar safety profile to that of twice-daily subcutaneous pasireotide,” the team wrote in the study.

“Long-acting pasireotide is an efficacious treatment option for some patients with Cushing’s disease who have persistent or recurrent disease after initial surgery or are not surgical candidates, and provides a convenient monthly administration schedule,” researchers concluded.


Delayed complications after transsphenoidal surgery for pituitary adenomas

World Neurosurg. 2017 Oct 5. pii: S1878-8750(17)31710-2. doi: 10.1016/j.wneu.2017.09.192. [Epub ahead of print]


Perioperative complications after transsphenoidal surgery for pituitary adenomas have been well documented in the literature; however, some complications can occur in a delayed fashion postoperatively and reports are sparse about their occurrence, management, and outcome.

Here, we describe delayed complications after transsphenoidal surgery and discuss the incidence, temporality from the surgery, and management of these complications based on the findings of studies that reported delayed postoperative epistaxis, delayed postoperative cavernous carotid pseudoaneurysm formation and rupture, vasospasm, delayed symptomatic hyponatremia (DSH), hypopituitarism, hydrocephalus, and sinonasal complications.

Our findings from this review revealed an incidence of 0.6-3.3% for delayed postoperative epistaxis at 1-3 weeks postoperatively, 18 reported cases of delayed carotid artery pseudoaneurysm formation at 2 days to 10 years postoperatively, 30 reported cases for postoperative vasospasm occurring 8 days postoperatively, a 3.6-19.8% rate of DSH at 4-7 days postoperatively, a 3.1% rate of new-onset hypopituitarism at 2 months postoperatively, and a 0.4-5.8% rate of hydrocephalus within 2.2 months postoperatively.

Sinonasal complications are commonly reported after transsphenoidal surgery, but spontaneous resolutions within 3-12 months have been reported. Although the incidence of some of these complications is low, providing preoperative counseling to patients with pituitary tumors regarding these delayed complications and proper postoperative follow-up planning is an important part of treatment planning.


carotid pseudoaneurysm; cerebrospinal fluid leak; delayed complications; epistaxis; hydrocephalus; hyponatremia; hypopituitarism; pituitary; sinonasal complication; transsphenoidal surgery; tumor

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