Faculty Bibliography

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.

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.

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.

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.

BACKGROUND:Surgery is the definitive treatment of Cushing's syndrome (CS) but medications may also be used as a first-line therapy. Whether preoperative medical treatment (PMT) affects postoperative outcome remains controversial. OBJECTIVE:(1) Evaluate how frequently PMT is given to CS patients across Europe; (2) examine differences in preoperative characteristics of patients who receive PMT and those who undergo primary surgery and (3) determine if PMT influences postoperative outcome in pituitary-dependent CS (PIT-CS). PATIENTS AND METHODS/METHODS:1143 CS patients entered into the ERCUSYN database from 57 centers in 26 countries. Sixty-nine percent had PIT-CS, 25% adrenal-dependent CS (ADR-CS), 5% CS from an ectopic source (ECT-CS) and 1% were classified as having CS from other causes (OTH-CS). RESULTS: < 0.01). Within 6 months of surgery, no differences in morbidity or remission rates were observed between SX and PMT groups. CONCLUSIONS:PMT may confound the interpretation of immediate postoperative outcome. Follow-up is recommended to definitely evaluate surgical results.

Somatostatin receptors are a pivotal target for treatment of pancreatic neuroendocrine tumors (pNET), either with somatostatin analogues (SSA) or radiolabeled SSA. The highest affinity target for the most commonly used SSA is the somatostatin receptor type 2 (sst

Mesenteric fibrosis (MF) surrounding a mesenteric mass is a hallmark feature of small intestinal neuroendocrine tumours (SI-NETs). Since this can induce intestinal obstruction, oedema and ischaemia, prophylactic resection of the primary tumour and mesenteric mass is often recommended. This study assessed the predictors for mesenteric metastasis and fibrosis and the effect of MF and palliative surgery on survival. A retrospective analysis of 559 patients with pathologically proven SI-NET and available CT-imaging data was performed. Clinical characteristics, presence of mesenteric mass and fibrosis on CT imaging and the effect of palliative abdominal surgery on overall survival were assessed. We found that MF was present in 41.4%. Older age, 5-HIAA excretion ≥67 μmol/24 h, serum CgA ≥121.5 μg/L and a mesenteric mass ≥27.5 mm were independent predictors of MF. In patients ≤52 years, mesenteric mass was less often found in women than in men (39% vs 64%, P = 0.002). Corrected for age, tumour grade, CgA and liver metastasis, MF was not a prognostic factor for overall survival. In patients undergoing palliative surgery, metastasectomy of mesenteric mass or prophylactic surgery did not result in survival benefit. In conclusion, we confirmed known predictors of MF and mesenteric mass and suggest a role for sex hormones as women ≤52 years have less often a mesenteric mass. Furthermore, the presence of MF has no effect on survival in a multivariate analysis, and we found no benefit of metastasectomy of mesenteric mass or prophylactic surgery on overall survival.