Faculty Bibliography

PURPOSE/OBJECTIVE:Peptide receptor radionuclide therapy (PRRT) with the radiolabeled somatostatin analogue [Lutetium-177-DOTA0-Tyr3]octreotate (177Lu-DOTATATE) is widely applied for inoperable metastatic small intestinal and nonfunctioning pancreatic neuroendocrine tumors (pNETs). The aim of this study is to describe the safety and efficacy of the treatment of functioning pNETs. METHODS:Patients were treated with up to four cycles of 177Lu-DOTATATE with an intended dose of 7.4 Gbq per cycle. Radiological (Response Evaluation Criteria in Solid Tumors 1.1), symptomatic, and biochemical response were analyzed retrospectively for all patients with a functioning pNET (insulinoma, gastrinoma, VIPoma, and glucagonoma) treated with 177Lu-DOTATATE. Quality of life (QOL) was assessed with the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core Module questionnaire. RESULTS:Thirty-four patients with a metastatic functioning pNET (European Neuroendocrine Tumor Society grade 1 or 2) were included: 14 insulinomas, 5 VIPomas, 7 gastrinomas, and 8 glucagonomas. Subacute hematological toxicity, grade 3 or 4 occurred in 4 patients (12%) and a hormonal crisis in 3 patients (9%). PRRT resulted in partial or complete response in 59% of patients and the disease control rate was 78% in patients with baseline progression. 71% of patients with uncontrolled symptoms had a reduction of symptoms and a more than 80% decrease of circulating hormone levels was measured during follow-up. After PRRT, median progression-free survival was 18.1 months (interquartile range: 3.3 to 35.7) with a concurrent increase in QOL. CONCLUSION/CONCLUSIONS:Treatment with 177Lu-DOTATATE is a safe and effective therapy resulting in radiological, symptomatic and biochemical response in a high percentage of patients with metastatic functioning pNETs. Hormonal crises occur relatively frequent and preventive therapy should be considered before and/or during PRRT.

Cushing's syndrome is associated with multisystem morbidity and, when suboptimally treated, increased mortality. Medical therapy is an option for patients if surgery is not successful and can be classified into pituitary-directed drugs, steroid synthesis inhibitors, and glucocorticoid receptor antagonists. In the last decade there have been new developments in each drug category. Targeting dopamine and somatostatin receptors on corticotroph adenomas with cabergoline or pasireotide, or both, controls cortisol production in up to 40% of patients. Potential new targets in corticotroph adenomas include the epidermal growth factor receptor, cyclin-dependent kinases, and heat shock protein 90. Osilodrostat and levoketoconazole are new inhibitors of steroidogenesis and are currently being evaluated in multicentre trials. CORT125134 is a new selective glucocorticoid receptor antagonist under investigation. We summarise the drug therapies for various forms of Cushing's syndrome and focus on emerging drugs and drug targets that have the potential for new and effective tailor-made pharmacotherapy for patients with Cushing's syndrome.

Hyponatraemia is a common electrolyte disturbance with multiple causes. We present a case of a 49-year-old Caucasian female with cholangiocarcinoma, who had a hyponatraemia which was initially assumed to be based on a syndrome of inappropriate antidiuretic hormone secretion as paraneoplastic phenomenon. At physical examination, hyperpigmentation was seen and multiple episodes with syncope were reported. Subsequent endocrine assessment with a synthetic adrenocorticotropin hormone (ACTH) stimulation test and measurement of ACTH levels revealed primary adrenal insufficiency also known as Morbus Addison. We started hydrocortisone and fludrocortisone replacement therapy, resulting in resolving of symptoms, hyponatraemia and hyperpigmentation.

Some biomarkers for functioning and non-functioning neuroendocrine neoplasms (NENs) are currently available. Despite their application in clinical practice, results should be interpreted cautiously. Considering the variable sensitivity and specificity of these parameters, there is an unmet need for novel biomarkers to improve diagnosis and predict patient outcome. Nowadays, several new biomarkers are being evaluated and may become future tools for the management of NENs. These biomarkers include (1) peptides and growth factors; (2) DNA and RNA markers based on genomics analysis, for example, the so-called NET test, which has been developed for analyzing gene transcripts in circulating blood; (3) circulating tumor/endothelial/progenitor cells or cell-free tumor DNA, which represent minimally invasive methods that would provide additional information for monitoring treatment response and (4) improved imaging techniques with novel radiolabeled somatostatin analogs or peptides. Below we summarize some future directions in the development of novel diagnostic and predictive/prognostic biomarkers in NENs. This review is focused on circulating and selected tissue markers.

CONTEXT/BACKGROUND:Corticosteroid-binding globulin (CBG) and albumin transport circulating cortisol. Cleavage of high-affinity CBG (haCBG) by neutrophil elastase at inflammatory sites causes cortisol release into tissues, facilitating immunomodulatory effects. OBJECTIVE:To determine whether depletion of haCBG is related to mortality in septic shock. DESIGN/METHODS:A single-center prospective observational cohort study of patients recruited with critical illness or septic shock, using serum samples collected at 0, 8, 24, 48 and 72 hours. Serum total and haCBG, and total and free cortisol were assayed directly. Glucocorticoid treatment was an exclusion criterion. Mortality was assessed at 28 days from Intensive Care Unit admission. RESULTS:Thirty septic shock (SS) and 42 nonseptic critical illness (CI) patients provided 195 serum samples. SS/CI patients had lower total CBG, haCBG and low-affinity CBG (laCBG) than controls. Total CBG and haCBG were significantly lower in septic shock patients who died than in those that survived (P < 0.009, P = 0.021, respectively). Total and free cortisol were higher in septic than nonseptic individuals. Free/total cortisol fractions were higher in those with low haCBG as observed in septic shock. However, cortisol levels were not associated with mortality. Albumin levels fell in sepsis but were not related to mortality. CONCLUSIONS:Low circulating haCBG concentrations are associated with mortality in septic shock. These results are consistent with an important physiological role for haCBG in cortisol tissue delivery in septic shock.

Neuroendocrine tumors (NETs) originate from the neuroendocrine cell system in the bronchial and gastrointestinal tract and can produce hormones leading to distinct clinical syndromes. Systemic treatment of patients with unresectable NETs aims to control symptoms related to hormonal overproduction and tumor growth. In the last decades prognosis has improved as a result of increased detection of early stage disease and the introduction of somatostatin analogs (SSAs) as well as several new therapeutic options. SSAs are the first-line medical treatment of NETs and can control hormonal production and tumor growth. The development of next-generation multireceptor targeted and radiolabelled somatostatin analogs, as well as target-directed therapies (as second-line treatment options) further improve progression-free survival in NET patients. To date, however, a significant prolongation of overall survival with systemic treatment in NET has not been convincingly demonstrated. Several new medical options and treatment combinations will become available in the upcoming years, and although preliminary results of preclinical and clinical trials are encouraging, large, preferrably randomized clinical studies are required to provide definitive evidence of their effect on survival and symptom control.

BACKGROUND/AIMS/OBJECTIVE:The current diagnostic workup of Cushing's syndrome (CS) requires various tests which only capture short-term cortisol exposure, whereas patients with endogenous CS generally have elevated long-term cortisol levels. Scalp hair assessment has emerged as a convenient test in capturing glucocorticoid concentrations over long periods of time. The aim of this multicenter, multinational, prospective, case-control study was to evaluate the diagnostic efficacy of scalp hair glucocorticoids in screening of endogenous CS. <br>Methods: We assessed the diagnostic performances of hair cortisol (HairF), hair cortisone (HairE), and sum of both (sumHairF+E), as measured by state-of-the-art LC-MS/MS technique, in untreated patients with confirmed endogenous CS (n=89), and community controls (n=295) from the population-based Lifelines cohort study. <br>Results: Both glucocorticoids were significantly elevated in CS patients when compared to controls. High diagnostic efficacy was found for HairF (area under the curve (AUC), 0.87 [95% CI, 0.83 to 0.92]), HairE (0.93 [0.89 to 0.96]) and sumHairF+E (0.92 [0.88 to 0.96]; all P<.001). Participants were accurately classified at optimal cut-off threshold in 86% of cases (81% sensitivity, 88% specificity, 94% negative predictive value (NPV)) for HairF, in 90% of cases (87% sensitivity, 90% specificity, 96% NPV) for HairE, and 87% of cases (86% sensitivity, 88% specificity, 95% NPV) for the sum. HairE was shown to be most accurate in differentiating CS patients from controls. <br>Conclusion: Scalp hair glucocorticoids, especially hair cortisone, can be seen as a promising biomarker in screening of CS. Its convenience in collection and workup additionally makes this feasible for first-line screening <br>.

Context:Increased renal sodium reabsorption contributes to hypertension in Cushing syndrome (CS). Renal sodium transporters can be analyzed noninvasively in urinary extracellular vesicles (uEVs). Objective:To analyze renal sodium transporters in uEVs of patients with CS and hypertension. Design:Observational study. Setting:University hospital. Participants:The uEVs were isolated by ultracentrifugation and analyzed by immunoblotting in 10 patients with CS and 7 age-matched healthy participants. In 7 patients with CS, uEVs were analyzed before and after treatment. Main Outcome Measure:Abundance of protein in uEVs. Results:The 10 patients with CS were divided in those with suppressed and nonsuppressed renin-angiotensin-aldosterone system (RAAS; n = 5 per group). Patients with CS with suppressed RAAS had similar blood pressure but significantly lower serum potassium than patients with CS with nonsuppressed RAAS. Compared with healthy participants, only patients with suppressed RAAS had higher phosphorylated Na+-K+-Cl- cotransporter type 2 (pNKCC2) and higher total and phosphorylated Na+-Cl- cotransporter (pNCC) in uEVs. Serum potassium but not urinary free cortisol correlated with pNKCC2, pNCC, and Na+-Cl- cotransporter (NCC) in uEVs. Treatment of CS reversed the increases in pNKCC2, NCC, and pNCC. Conclusions:CS increases renal sodium transporter abundance in uEVs in patients with hypertension and suppressed RAAS. Potassium has recently been identified as an important driver of NCC activity, and low serum potassium may also contribute to increased renal sodium reabsorption and hypertension in CS. These results may also be relevant for hypertension induced by exogenous glucocorticoids.

OBJECTIVE:Hypercortisolism in Cushing's syndrome (CS) is associated with impaired health-related quality of life (HRQoL), which may persist despite remission. We used the data entered into the European Registry on Cushing's syndrome (ERCUSYN) to evaluate if patients with CS of pituitary origin (PIT-CS) have worse HRQoL, both before and after treatment than patients with adrenal causes (ADR-CS). METHODS:Data from 595 patients (492 women; 83%) who completed the CushingQoL and/or EQ-5D questionnaires at baseline and/or following treatment were analysed. RESULTS:At baseline, HRQoL did not differ between PIT-CS (n = 293) and ADR-CS (n = 120) on both EuroQoL and CushingQoL. Total CushingQoL score in PIT-CS and ADR-CS was 41 ± 18 and 44 ± 20, respectively (P = .7). At long-time follow-up (>1 year after treatment) total CushingQoL score was however lower in PIT-CS than ADR-CS (56 ± 20 vs 62 ± 23; P = .045). In a regression analysis, after adjustment for baseline age, gender, remission status, duration of active CS, glucocorticoid dependency and follow-up time, no association was observed between aetiology and HRQoL. Remission was associated with better total CushingQoL score (P < .001), and older age at diagnosis with worse total score (P = .01). Depression at diagnosis was associated with worse total CushingQoL score at the last follow-up (P < .001). CONCLUSION:PIT-CS patients had poorer HRQoL than ADR-CS at long-term follow-up, despite similar baseline scoring. After adjusting for remission status, no interaetiology differences in HRQoL scoring were found. Age and presence of depression at diagnosis of CS may be potential predictors of worse HRQoL regardless of CS aetiology.

BACKGROUND:A substantial proportion of all pheochromocytomas is currently detected during the evaluation of an adrenal incidentaloma. Recently, it has been suggested that biochemical testing to rule out pheochromocytoma is unnecessary in case of an adrenal incidentaloma with an unenhanced attenuation value ≤10 Hounsfield Units (HU) at computed tomography (CT). OBJECTIVES/OBJECTIVE:We aimed to determine the sensitivity of the 10 HU threshold value to exclude a pheochromocytoma. METHODS:Retrospective multicenter study with systematic reassessment of preoperative unenhanced CT scans performed in patients in whom a histopathologically proven pheochromocytoma had been diagnosed. Unenhanced attenuation values were determined independently by two experienced radiologists. Sensitivity of the 10 HU threshold was calculated, and interobserver consistency was assessed using the intraclass correlation coefficient (ICC). RESULTS:214 patients were identified harboring a total number of 222 pheochromocytomas. Maximum tumor diameter was 51 (39-74) mm. The mean attenuation value within the region of interest was 36 ± 10 HU. Only one pheochromocytoma demonstrated an attenuation value ≤10 HU, resulting in a sensitivity of 99.6% (95% CI: 97.5-99.9). ICC was 0.81 (95% CI: 0.75-0.86) with a standard error of measurement of 7.3 HU between observers. CONCLUSION/CONCLUSIONS:The likelihood of a pheochromocytoma with an unenhanced attenuation value ≤10 HU on CT is very low. The interobserver consistency in attenuation measurement is excellent. Our study supports the recommendation that in patients with an adrenal incidentaloma biochemical testing for ruling out pheochromocytoma is only indicated in adrenal tumors with an unenhanced attenuation value >10 HU.