Publications by authors named "Gerlof D Valk"

Multiple Endocrine Neoplasia type 1 (MEN1) Clinical Practice Guidelines (2012) are predominantly based on expert opinion due to limited available evidence at the time, leaving room for interpretation and variation in practices. Evidence on the natural course of MEN1-related neuroendocrine tumours (NET) and the value of screening programs has increased and new imaging techniques have emerged. The aim of this study is to provide insight in the current practices of screening and surveillance for MEN1-related NETs in ENETS Centers of Excellence (CoEs).

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  • Glucagonomas are special tumors in the pancreas that cause a syndrome and were studied in six patients to understand their features better.
  • These tumors were mostly large and showed a common skin symptom called necrolytic migratory erythema in all patients.
  • The tumors had specific changes in their genes and were linked to serious aggressive behavior, which means they can spread or grow badly in some patients.
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Objective: Immune checkpoint inhibitors (ICIs) are revolutionary in oncology but may cause immune-related (IR) side effects, such as hypophysitis. Treatment with anti-PD-(L)1, anti-CTLA-4 or anti-CLTA-4/PD-1 may induce hypophysitis, but little is known about the differences in clinical presentation or need for different treatment. We analyzed the differences of anti-PD-(L)1, anti-CTLA-4 and anti-CTLA-4/PD-1 induced hypophysitis.

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Tumor markers often remain elevated after intended curative resection of medullary thyroid carcinoma (MTC). The aim of this study was to determine the expression of αβ, a promising theranostics target, in MTC and its metastases. Aβ expression was analyzed in 104 patients using a tissue microarray and correlated with clinicopathological variables and survival.

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Neuroendocrine neoplasms (NENs) comprise well-differentiated neuroendocrine tumors (NETs) and poorly differentiated neuroendocrine carcinomas (NECs). Treatment options for patients with NENs are limited, in part due to lack of accurate models. We establish patient-derived tumor organoids (PDTOs) from pulmonary NETs and derive PDTOs from an understudied subtype of NEC, large cell neuroendocrine carcinoma (LCNEC), arising from multiple body sites.

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  • Targeted screening programs help people at higher risk of cancer, like those with multiple endocrine neoplasia (MEN), by checking for tumors from an early age.
  • Patients with MEN often feel scared about getting sick and how it might affect their families, but not much is known about how regular screenings impact their lives.
  • The study found that patients have mixed feelings about screenings; while they provide some control over their health, they can also create uncertainty and are heavily influenced by their family experiences.
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Purpose: Patients with multiple endocrine neoplasia type 1 (MEN1) are predisposed to develop duodenopancreatic neuroendocrine tumors (dpNETs), and metastatic dpNET is the primary cause of disease-related mortality. Presently, there is a paucity of prognostic factors that can reliably identify patients with MEN1-related dpNETS who are at high risk of distant metastasis. In the current study, we aimed to establish novel circulating molecular protein signatures associated with disease progression.

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Background: Surgical resection is the standard of care for the treatment of pancreatic neuro-endocrine tumors (pNETs) in patients with Multiple Endocrine Neoplasia Type 1 (MEN1). However, surgery can cause significant short- and long-term morbidity. Magnetic resonance-guided radiotherapy (MRgRT) is a potential effective treatment with little side effects.

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  • A study was conducted to evaluate the effectiveness of menin immunohistochemistry in diagnosing multiple endocrine neoplasia type 1 (MEN1) syndrome, particularly in parathyroid adenomas.
  • The research analyzed parathyroid tumors from patients with MEN1 and various non-MEN1 conditions, finding that menin loss was present in all MEN1 patients but only in a small percentage of non-MEN1 patients.
  • The results indicate that menin immunohistochemistry is a reliable tool for confirming MEN1 syndrome and can aid in cases where genetic testing results are ambiguous.
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Pancreatic neuroendocrine tumors (PNETs) occur in < 1/100,000 patients and most are nonfunctioning (NF). Approximately 5% occur as part of multiple endocrine neoplasia type 1. Anatomic and molecular imaging have a pivotal role in the diagnosis, staging and active surveillance.

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Introduction: The rarity of neuroendocrine tumors (NETs) and their heterogeneous presentation complicate the identification of risk factors for their development and natural course. Several tumor-specific prognostic factors have been identified, but less attention has been given to lifestyle factors as risk and prognostic factors. This review aimed to identify studies on smoking, alcohol use, physical activity, diet, body mass index (BMI), and diabetes and their association with the development and course of gastroenteropancreatic (GEP-) NETs.

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Background: In multiple endocrine neoplasia type 1 (MEN1), pancreatic neuroendocrine tumors (PanNETs) have a high prevalence and represent the main cause of death. This study aimed to assess the diagnostic accuracy of the currently used conventional pancreatic imaging techniques and the added value of fine needle aspirations (FNAs).

Methods: Patients who had at least one imaging study were included from the population-based MEN1 database of the DutchMEN Study Group from 1990 to 2017.

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  • Carcinoid heart disease (CHD) is a serious condition caused by high levels of serotonin from certain tumors, mainly affecting the right side of the heart and making it harder for patients to survive.
  • This study looked at 84 patients with CHD over three time periods from 1984 to 2018 and found that survival rates have improved a lot in recent years.
  • The research showed that valve replacement surgery helps patients live longer and that a blood test called NT-proBNP can help doctors understand how sick a person is with CHD.
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Objective: Up to now, serial NETest measurements in individuals assessing the disease course of gastroenteropancreatic neuroendocrine tumors (GEPNETs) at long-term follow-up and treatment response were not studied.

Design: The study was a longitudinal validation study of serial NETest measurements - a blood-based gene expression signature - in 132 patients with GEPNETs on therapy or watch-and-wait strategy.

Methods: Serial samples were collected during 46 (range: 6-71) months of follow-up.

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Objective: We aimed to investigate the postoperative trend in blood pressure (BP)-related outcomes [BP and antihypertensive (AHT) drug use] during the year following adrenalectomy for primary aldosteronism (PA) to determine the optimal timing for outcome assessment and to determine the necessary follow-up length.

Background: Since the course of BP-related outcomes after adrenalectomy is unknown, the optimal timing of outcome assessment and follow-up duration are not clear.

Methods: In this retrospective single center cohort study, we used a prospectively collected database with all patients referred for difficult-to-control-hypertension-analysis.

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Introduction: Small intestinal neuroendocrine tumors (SI-NETs) often present with metastatic disease. An ongoing debate exists on whether to perform primary tumor resection (PTR) in patients with stage IV SI-NETs, without symptoms of the primary tumor and inoperable metastatic disease.

Objective: The aim of this study was to compare a treatment strategy of upfront surgical resection versus a surveillance strategy of watch and wait.

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Carcinoid heart disease (CHD) is a rare fibrotic cardiac complication of neuroendocrine tumors. Besides known biomarkers N-Terminal pro-B-type natriuretic peptide (NT-proBNP) and serotonin, activin A, connective tissue growth factor (CTGF), and soluble suppression of tumorigenicity 2 (sST2) have been suggested as potential biomarkers for CHD. Here, we validated the predictive/diagnostic value of these biomarkers in a case-control study of 114 patients between 1990 and 2021.

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Objective: To evaluate the usefulness of [18F]fluorodeoxyglucose (FDG) positron emissive tomography (PET)/CT in patients with low detectable thyroglobulin levels suspicious for persistent or recurrent differentiated thyroid cancer (DTC).

Methods: A retrospective case series study evaluating FDG PET/CT in patients with detectable thyroglobulin (Tg) levels (≥0.20 and <10.

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Background: Surgical resection is the only potentially curative treatment for pancreatic neuroendocrine tumors. The choice for the type of procedure is influenced by the expected oncological benefit and the anticipated risk of procedure-specific complications. Few studies have focused on complications in these patients.

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This review provides an overview of novel insights in the clinical management of patients with Multiple Endocrine Neoplasia Type 1, focusing on the last decade since the last update of the MEN1 guidelines. With regard to Diagnosis: Mutation-negative patients with 2/3 main manifestations have a different clinical course compared to mutation-positive patients. As for primary hyperparathyroidism: subtotal parathyroidectomy is the initial procedure of choice.

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Von Hippel-Lindau (VHL) disease is an autosomal dominant disorder characterized by the development of multi-organ neoplasms. Among the manifestations of VHL are pancreatic neuroendocrine neoplasms (panNENs). In order to detect these lesions in a timely manner, patients are enrolled in a surveillance program, in accordance with the several existing VHL guidelines.

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Thyroid cancer is the most common endocrine malignancy in children. A rising incidence has been reported worldwide. Possible explanations include the increased use of enhanced imaging (leading to incidentalomas) and an increased prevalence of risk factors.

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