Rapid decrease in adrenal responsiveness to ACTH stimulation after successful pituitary surgery in patients with Cushing's disease.

OBJECTIVE: The aim of this study was to investigate the effects of transsphenoidal surgery (TS) on the adrenal sensitivity to ACTH (adrenocorticotropin) stimulation in patients with Cushing's disease (CD). METHODS: We measured the cortisol response to 1 µg synthetic ACTH (1-24) 6 days after pituitary surgery in 45 patients with CD. Mean follow-up period was 56·5 months (SE 4·7). RESULTS: In 24 of 28 patients in sustained remission after pituitary surgery, peak cortisol concentrations below 774 nm (28·0 µg/dl) were recorded after stimulation with 1 µg synthetic ACTH (86%). Two patients with recurrent disease after initial remission (late relapse) also showed ACTH-stimulated peak cortisol levels below 774 nM. Fourteen of 15 patients with persistent CD after surgery (early failure) showed absolute peak cortisol levels >774 nm in response to ACTH stimulation. CONCLUSION: Patients in remission after pituitary surgery for CD showed a rapid decrease of adrenal responsiveness to exogenous ACTH stimulation. This phenomenon may be explained by ACTH-receptor down-regulation in the adrenal cortex after complete removal of the pituitary corticotroph adenoma. In our study, the postoperative low-dose ACTH stimulation test had a sensitivity of 93% and a specificity of 87% in predicting immediate remission of CD after pituitary surgery.

Biochemical predictors of outcome of pituitary surgery for Cushing's disease.

OBJECTIVE: Transsphenoidal surgery (TS) is the primary therapy for Cushing's disease (CD). The aims of this retrospective study were twofold: (i) investigate early and late results of TS for CD, and (ii) evaluate various postoperative tests in order to predict the outcome of TS. METHODS: We reviewed the long-term outcome in 79 patients with CD who underwent TS (median follow-up 84 months, range 6-197). Within 2 weeks after surgery, morning serum cortisol concentrations were obtained (n = 78) and corticotropin-releasing hormone (CRH) (n = 53) and metyrapone tests (n = 72) were performed. Three groups of outcome were identified: sustained remission, early failure (persistent CD), and late relapse. RESULTS: Immediate postoperative remission was achieved in 51 patients (65%), whereas 28 patients (35%) had persistent CD after TS. Ten patients developed recurrent CD after initial remission (20%). Morning cortisol: all relapses but one recorded serum cortisol >50 nmol/l. A cortisol threshold value of 200 nmol/l has a positive predictive value of 79% for immediate surgical failure (negative predictive failure [NPV] 97%). CRH test: CRH-stimulated peak cortisol > or =600 nmol/l predicted early failure in 78% (NPV 100%). All relapses recorded CRH-stimulated peak cortisol >or =485 nmol/l. Metyrapone test: 11-deoxycortisol >or =345 nmol/l predicted an early failure in 86% of cases (NPV 94%). CONCLUSION: Predictive factors of surgical failure are morning cortisol >or =200 nmol/l, 11-deoxycortisol >or =345 nmol/l after metyrapone and CRH-stimulated cortisol >or =600 nmol/l. CRH and/or metyrapone testing are not superior to morning cortisol concentration in the prediction of outcome of TS. Careful long-term follow-up remains necessary independent of the outcome of biochemical testing.

Cushing's syndrome due to ectopic ACTH production by (neuroendocrine) prostate carcinoma.

Ectopic adrenocorticotropin (ACTH) secretion accounts for less than 10% of all causes of endogenous Cushing's syndrome (CS) and is usually associated with neuroendocrine tumors and small cell carcinoma of the lung. We report the case of a 62-year-old man with CS due to ectopic ACTH production by small cell carcinoma of the prostate. He presented with severe hypercortisolism and associated symptoms. Plasma neuron specific enolase (NSE) was grossly elevated. Despite performing a laparoscopic bilateral adrenalectomy, the patient died as a result of sepsis with multi-organ failure. Post-mortem immunohistochemical staining of prostate tumor tissue showed ACTH expression. ACTH staining was also performed in four additional patients with small cell carcinoma of the urinary tract without CS. None of these additional cases showed a positive staining for ACTH. Although a rare cause of ectopic ACTH production, neuroendocrine prostate carcinoma should be considered in male patients with Cushing's syndrome, in particular in those with an occult source of ACTH overproduction.

Paraganglioma of the urinary bladder.

Since paragangliomas of the urinary bladder are rare and not easily recognised, histological examination is often the only leading key to diagnosis. We report on a patient with a paraganglioma of the urinary bladder. Although the patient presented with classical signs and symptoms, these were only appreciated after histological examination of a transurethral resection specimen had elucidated the correct diagnosis.

Adrenal Cushing's syndrome during pregnancy.

Cushing syndrome (CS) during pregnancy is a rare condition with only a few cases reported in the literature. Misdiagnosis of CS is common because of overlapping features like fatigue, weight gain, striae and emotional changes that can occur during normal pregnancy. Changes in maternal hormones and their binding proteins complicate assessment of glucocorticoid hormone levels during gestation. CS during pregnancy is most frequently due to an adrenal adenoma and to a lesser degree to adrenocorticotropic hormone (ACTH) hypersecretion by a pituitary adenoma. Furthermore, aberrant expression of luteinizing hormone (LH) receptors in the adrenal cortex has been suggested to be involved in the pathogenesis of adrenal CS during pregnancy. We report three pregnant women with ACTH-independent Cushing's syndrome and an adrenal tumor. After uncomplicated delivery, patient 1 underwent in vivo testing for aberrant hormone receptor expression by the adenoma. Cortisol responses were found after administration of luteinizing hormone-releasing hormone (LHRH), human chorionic gonadotropin (hCG), glucagon, vasopressin and a standard mixed meal. All patients were treated with laparoscopic adrenalectomy. Adrenal tumor tissue of two patients showed positive immunohistochemical staining of LH receptors. Considering the cortisol responses to LHRH and hCG, and the development of CS during pregnancy in these patients, it is likely that ACTH-independent hypercortisolism was induced by the pregnancy-associated rise in hCG levels that activated aberrantly expressed LH receptors in the adrenal adenoma. Remarkably, adrenal adenomas may simultaneously express multiple aberrant receptors and individual ligands may play a role in the regulation of cortisol production in CS during pregnancy.

Prevalence and clinical features of the ectopic ACTH syndrome in patients with gastroenteropancreatic and thoracic neuroendocrine tumors.

OBJECTIVE: Several series report on the relative contribution of ectopic ACTH syndrome (EAS) in the spectrum of Cushing's syndrome. However, prevalence of EAS in patients with thoracic or gastroenteropancreatic neuroendocrine tumors (GEP-NETs) is currently unknown. DESIGN: We assessed, in a tertiary referral center, the prevalence of EAS in a large cohort of thoracic and GEP-NET patients including clinical, biochemical, and radiological features; management; and treatment outcome. METHODS: In total, 918 patients with thoracic or GEP-NETs were studied (1993-2012). Multiple endocrine neoplasia type 1 and small cell lung carcinoma patients were excluded. Differentiation between synchronous, metachronous, and cyclic occurrence of EAS was made. RESULTS: Out of the 918 patients with thoracic and GEP-NETs (469 males and 449 females; median age 58.7 years (range: 17.3-87.3)), 29 patients (3.2%) had EAS (ten males and 19 females; median age 48.1 years (range: 24.7-77.9)). EAS occurred synchronously in 23 patients (79%), metachronously in four patients (14%), and cyclical in two patients (7%) respectively. NETs causing EAS included lung/bronchus (n=9), pancreatic (n=9), and thymic (n=4). In four patients, the cause of EAS was unknown (n=4). Median overall survival (OS) of non-EAS thoracic and GEP-NET patients was 61.2 months (range: 0.6-249.4). Median OS of EAS patients was 41.4 months (range: 2.2-250.9). After comparison, only the first 5-year survival was significantly shorter (P=0.013) in EAS patients. CONCLUSION: Prevalence of EAS in this large cohort of patients with thoracic and GEP-NETs was 3.2%. EAS was mostly caused by thoracic and pancreatic NETs. First 5-year survival of EAS patients was shorter compared with non-EAS patients.

[Posttraumatic hypopituitarism]. / Posttraumatisch hypopituïtarisme.

A 39-year-old woman was admitted with complaints of weight gain, a decreased sense of well-being and amenorrhoea. One and a half year prior to admission she had been involved in a serious road accident and had spent several days in coma due to an epidural haematoma. She was found to have hypopituitarism with deficient somatotropic and gonadotropic axes, as well as mild hyperprolactinaemia, probably due to a pituitary stalk lesion. All patients with severe trauma to the skull are at risk of developing posttraumatic hypopituitarism, so that pituitary function testing should be performed routinely, certainly in the presence of symptoms.

Differentiating between Cushing's disease and pseudo-Cushing's syndrome: comparison of four tests.

OBJECTIVE: To evaluate the diagnostic performance of four different tests in order to differentiate between Cushing's disease (CD) and pseudo-Cushing's syndrome (PCS). METHODS: In this prospective study, a total of 73 patients with clinical features of hypercortisolism and insufficient suppression of serum cortisol after 1 mg overnight dexamethasone and/or an elevated excretion of cortisol in 24-h urine samples were included. The circadian rhythm of serum cortisol levels as well as midnight serum cortisol (MserC) levels were assessed in all 73 patients. Late-night salivary cortisol (LNSC) concentrations were obtained in 44 patients. The dexamethasone-CRH (Dex-CRH) test was performed in 54 patients. RESULTS: FIFTY-THREE PATIENTS WERE DIAGNOSED WITH CD AND SUBSEQUENTLY TREATED. TWENTY PATIENTS WERE CLASSIFIED AS HAVING PSC. SERUM CORTISOL CIRCADIAN RHYTHM: the diurnal rhythmicity of cortisol secretion was retained in PCS. A cortisol midnight:morning ratio of >0.67 is highly suggestive of CD (positive predictive value (PPV) 100% and negative predictive value (NPV) 73%). MserC concentration >243 nmol/l has a PPV of 98% in predicting true CD (NPV 95%). LNSC level >9.3 nmol/l predicted CD in 94% of patients (NPV 100%). Dex-CRH test: after 2 days of dexamethasone suppression, a CRH-stimulated cortisol level >87 nmol/l (T=15 min) resulted in a PPV of 100% and an NPV of 90%. CONCLUSION: The Dex-CRH test as well as a single measurement of cortisol in serum or saliva at late (mid-) night demonstrated high diagnostic accuracy in differentiating PCS from true CD.