Guidelines for surveillance of patients with von Hippel-Lindau disease: Consensus statement of the International VHL Surveillance Guidelines Consortium and VHL Alliance

Familial and early recurrent pheochromocytoma in a child with a novel in-frame duplication variant of VHL

Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors often linked to underlying genetic variants. Genetic analysis can promote gene-adjusted, specific follow-up, and surveillance protocols for both patients and their families at risk. We report the case of a 7-yr-old boy with bilateral pheochromocytoma, which recurred a year after partial adrenalectomy. The patient's father developed bilateral pheochromocytomas at 25 yr of age. Both individuals possessed a novel heterogeneous in-frame duplication germline variant of VHL, yet neither exhibited other clinical manifestations of von Hippel-Lindau disease (VHL). Traditionally, VHL missense mutations have been associated with a higher risk of PPGL development, whereas truncating mutations typically confer a lower risk. In-frame duplication variants are rarely observed in patients with VHL but may lead to changes in the three-dimensional structure of the translated protein, similar to truncating variants. Our analysis suggests that these in-frame duplications of amino acids in specific regions may cause pheochromocytomas in a manner similar to missense variants. Further accumulation of VHL cases with various genotypes and standardized open-access worldwide databases, including longitudinal and specific clinical data linked to genotypes, is required. It is crucial to consider genetic analyses for pediatricians who may diagnose childhood-onset PPGL.

Anesthesia Management in Hereditary Pheochromocytoma and Paraganglioma: Updated Insights into Clinical Features and Perioperative Care

Approximately 40% of pheochromocytoma and paraganglioma (PPGL) cases are familial, typically presenting earlier with more complex symptoms. This paper synthesizes literature and guidelines to inform on clinical characteristics and perioperative care for PPGL. Pheochromocytoma in von Hippel-Lindau (VHL) disease exhibits heightened secretion activity without significant perioperative hemodynamic changes. Tumors in multiple endocrine neoplasia type 2 (MEN2) have a stronger endocrine function, which may induce hemodynamic fluctuations during surgery. Therefore, pheochromocytoma screening is essential at all stages of MEN2. Neurofibromatosis type 1 (NF1) often presents multisystem lesions and can result in difficult airway. Pheochromocytoma should be evaluated when NF1 patients present hypertension. Pheochromocytoma and paraganglioma type 5 may present multiple lesions of pheochromocytoma or paraganglioma. In summary, hereditary PPGLs may present with severe lesions in other systems, beyond tumor function. A multi-disciplinary team (MDT) approach is often invaluable in perioperative management.

Multiple Primary Paragangliomas in a Pediatric Patient With von Hippel Lindau: A Diagnostic Dilemma

Pheochromocytoma and paragangliomas (PPGLs) are rare chromaffin cell tumors arising from neural crest tissue. The majority of these tumors are nonmetastatic, with complete cure achieved through surgical resection. PPGLs have been associated with several hereditary cancer syndromes, including von Hippel-Lindau (VHL). We present the case of a 10-year-old patient with VHL and a history of 2 asynchronous pheochromocytomas requiring bilateral adrenalectomies who presented with a new 1.2 cm × 1.3 cm × 1.5 cm nodular structure between the superior pole of the right kidney and the intrahepatic inferior vena cava. The patient was noted to have hypertension but was otherwise asymptomatic. Positron emission tomography-DOTA-(Tyr)3-octreotate revealed a metabolically active retrocrural lymph node. Based on these imaging findings and laboratory studies showing elevated plasma normetanephrine, clinical suspicion was highest for metastatic pheochromocytoma. The patient underwent surgical resection of multiple abdominal tumors. Pathology ultimately favored a diagnosis of multiple primary paragangliomas rather than metastatic disease. With this shift in diagnosis, the patient was managed with surgery alone. One year later, he has no signs of disease recurrence. Long-term surveillance imaging and screening with fractionated plasma metanephrines is indicated to monitor for new tumors in the setting of VHL and 3 prior endocrine tumors.

Understanding Adult Central Nervous System Hemangioblastomas: A Systematic Review

BACKGROUND

Adult hemangioblastomas (HBs) are rare World Health Organization central nervous system (CNS) grade 1 tumors, particularly affecting the posterior cranial fossa. They exhibit a gender bias, impacting men in their fifth and sixth decades of life and manifesting sporadically or as part of von Hippel Lindau disease. Understanding the intricacies of CNS HBs is crucial for clinical decision-making.

METHODS

A systematic review of 576 articles was conducted following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Eligibility criteria included 3189 adult cases of CNS HBs. Data on patient demographics, tumor characteristics, symptoms, treatment modalities, complications, and outcomes were systematically extracted and synthesized.

RESULTS

The review revealed a heterogeneous demographic distribution, with a male predominance. The median age at diagnosis was 44.7 years. Cranial HBs were more commonly located in the infratentorial (73%) than supratentorial (27%) compartments. Spinal HBs were mostly located in the cervical spine (44.3%), followed by thoracic (36.7%) and lumbar spine (12%). Clinical symptoms varied by location, emphasizing the importance of anatomical considerations. Surgical intervention-total resection (82% of cases)-was the preferred treatment modality, while radiotherapy was less common. Histological examination and immunohistochemistry aided in accurate diagnosis. Complications were location-specific, with intracranial complications more common in infratentorial tumors. Overall, favorable outcomes were prevalent (78% of cases), with low mortality rates.

CONCLUSIONS

Adult CNS HBs present with diverse characteristics and clinical manifestations. Surgical intervention remains the mainstay treatment; ongoing research into genetic and molecular mechanisms may enhance our understanding of tumor pathology and lead to improved management strategies in the future.

Consensus Guidelines for Ocular Surveillance of von Hippel-Lindau Disease

PURPOSE

To develop guidelines for ocular surveillance and early intervention for individuals with von Hippel-Lindau (VHL) disease.

DESIGN

Systematic review of the literature.

PARTICIPANTS

Expert panel of retina specialists and ocular oncologists.

METHODS

A consortium of experts on clinical management of all-organ aspects of VHL disease was convened. Working groups with expertise in organ-specific features of VHL disease were tasked with development of evidence-based guidelines for each organ system. The ophthalmology subcommittee formulated questions for consideration and performed a systematic literature review. Evidence was graded for topic quality and relevance and the strength of each recommendation, and guideline recommendations were developed.

RESULTS

The quality of evidence was limited, and no controlled clinical trial data were available. Consensus guidelines included: (1) individuals with known or suspected VHL disease should undergo periodic ocular screening (evidence type, III; evidence strength, C; degree of consensus, 2A); (2) patients at risk of VHL disease, including first-degree relatives of patients with known VHL disease, or any patient with single or multifocal retinal hemangioblastomas (RHs), should undergo genetic testing for pathologic VHL disease gene variants as part of an appropriate medical evaluation (III/C/2A); (3) ocular screening should begin within 12 months after birth and continue throughout life (III/C/2A); (4) ocular screening should occur approximately every 6 to 12 months until 30 years of age and then at least yearly thereafter (III/C-D/2A); (5) ocular screening should be performed before a planned pregnancy and every 6 to 12 months during pregnancy (IV/D/2A); (6) ultra-widefield color fundus photography may be helpful in certain circumstances to monitor RHs, and ultra-widefield fluorescein angiography may be helpful in certain circumstances to detect small RHs (IV/D/2A); (7) patients should be managed, whenever possible, by those with subspecialty training, with experience with VHL disease or RHs, or with both and ideally within the context of a multidisciplinary center capable of providing multiorgan surveillance and access to genetic testing (IV/D/2A); (8) extramacular or extrapapillary RHs should be treated promptly (III/C/2A).

CONCLUSIONS

Based on available evidence from observational studies, broad agreement was reached for a strategy of lifelong surveillance and early treatment for ocular VHL disease. These guidelines were endorsed by the VHL Alliance and the International Society of Ocular Oncology and were approved by the American Academy of Ophthalmology Board of Trustees.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Belzutifan: a novel therapeutic for the management of von Hippel-Lindau disease and beyond

The identification of the VHL gene and its role in regulating the hypoxia-inducible factor signaling pathway has helped to revolutionize the treatment of renal cell carcinoma (RCC). Belzutifan is a novel small-molecule inhibitor of hypoxia-inducible factor 2α which has demonstrated efficacy in treating von Hippel-Lindau (VHL) disease, earning regulatory approvals for this indication. There is also early evidence for efficacy in sporadic RCC. Belzutifan has a favorable safety profile. Several clinical trials are currently ongoing, which should help in identifying this promising drug's role in RCC and beyond. This review summarizes the history, pharmacology and clinical evidence for belzutifan use to date, and also explores unanswered questions as they relate to this novel therapeutic agent.

Diversities of Mechanism in Patients with VHL Syndrome and diabetes: A Report of Two Cases and Literature Review

Background

Von Hippel-Lindau (VHL) syndrome is characterized by tumorous lesions affecting multiple organs. Pancreatic involvement in VHL syndrome can present as endocrine tumors and pancreatic cysts, which can interfere with both exocrine and endocrine functions of the pancreas. Diabetes is an uncommon complication of VHL syndrome.

Purpose

This study aims to summarize the various mechanisms of diabetes in VHL syndrome by reporting two cases and conducting a literature review.

Methods

We analyzed the clinical and imaging data of two patients with VHL syndrome and diabetes. Additionally, we reviewed the existing literature to explore the clinical diversities and management strategies for VHL syndrome complicated with diabetes.

Results

The first patient presented with liver metastasis of pancreatic neuroendocrine tumor and multiple pheochromocytoma. After surgery, the patient's diabetic control improved, as evidenced by a significant reduction in insulin dosage. This indicates a potential insulin resistance due to elevated metanephrine levels prior to surgery and partial insulin deficiency caused by distal pancreatectomy. The second patient had multiple hemangioblastomas, as well as multiple pancreatic cysts and positive pancreatic islet autoantibodies. Diabetes in this case may be attributed to pancreatic lesions and the coexistence of autoimmune insulitis. A literature review of other patients with VHL combined with diabetes revealed multiple mechanisms, including increased catecholamine levels, pancreatic lesions, surgical removal of pancreatic tissue, endocrine treatment, and possibly the coexistence of autoimmune insulitis.

Conclusion

VHL syndrome complicated with diabetes involves diverse mechanisms.

Predictors of Progression in a Series of 81 Adult Patients Surgically Managed for an Intracranial Hemangioblastoma: Implications for the Postoperative Follow-Up

The aim was to identify predictors of progression in a series of patients managed for an intracranial hemangioblastoma, in order to guide the postoperative follow-up modalities. The characteristics of 81 patients managed for an intracranial hemangioblastoma between January 2000 and October 2022 were retrospectively analyzed. The mean age at diagnosis was of 48 ± 16 years. Eleven (14%) patients had von Hippel-Lindau disease. The most frequent tumor location was the cerebellar hemispheres (n = 51, 65%) and 11 (14%) patients had multicentric hemangioblastomas. A gross total resection was achieved in 75 (93%) patients. Eighteen (22%) patients had a local progression, with a median progression-free survival of 56 months 95% CI [1;240]. Eleven (14%) patients had a distant progression (new hemangioblastoma and/or growth of an already known hemangioblastoma). Local progression was more frequent in younger patients (39 ± 14 years vs. 51 ± 16 years; p = 0.005), and those with von Hippel-Lindau disease (n = 8, 44% vs. n = 3, 5%, p < 0.0001), multiple cerebral locations (n = 3, 17% vs. n = 2, 3%, p = 0.02), and partial tumoral resection (n = 4, 18% vs. n = 1, 2%, p = 0.0006). Therefore, it is advisable to propose a postoperative follow-up for at least 10 years, and longer if at least one predictor of progression is present.

Hereditary Renal Cancer Syndromes

Familial kidney tumors represent a rare variety of hereditary cancer syndromes, although systematic gene sequencing studies revealed that as many as 5% of renal cell carcinomas (RCCs) are associated with germline pathogenic variants (PVs). Most instances of RCC predisposition are attributed to the loss-of-function mutations in tumor suppressor genes, which drive the malignant progression via somatic inactivation of the remaining allele. These syndromes almost always have extrarenal manifestations, for example, von Hippel-Lindau (VHL) disease, fumarate hydratase tumor predisposition syndrome (FHTPS), Birt-Hogg-Dubé (BHD) syndrome, tuberous sclerosis (TS), etc. In contrast to the above conditions, hereditary papillary renal cell carcinoma syndrome (HPRCC) is caused by activating mutations in the MET oncogene and affects only the kidneys. Recent years have been characterized by remarkable progress in the development of targeted therapies for hereditary RCCs. The HIF2aplha inhibitor belzutifan demonstrated high clinical efficacy towards VHL-associated RCCs. mTOR downregulation provides significant benefits to patients with tuberous sclerosis. MET inhibitors hold promise for the treatment of HPRCC. Systematic gene sequencing studies have the potential to identify novel RCC-predisposing genes, especially when applied to yet unstudied populations.

New Prospects on Neuroimaging in Von Hippel Lindau Disease-A Narrative Review

(1) Background: Hemangiomas in Von Hippel-Lindau (VHL) syndrome patients are typically benign but pose threats due to their vital locations involving the central nervous system and the retina. An MRI is currently recommended as the gold standard for tumors associated with VHL in the head region. This narrative review aims to comprehensively outline current standards and recent findings related to imaging of retinal and CNS hemangiomas in Von Hippel-Lindau syndrome. (2) Material and Methods: A review in adherence to PRISMA guidelines using the search string "Von Hippel-Lindau hemangioblastoma imaging" was conducted on PUBMED and SCOPUS databases. (3) Results: After reviewing 455 titles and abstracts, 20 publications fulfilling the inclusion criteria were analyzed. The analysis included studies describing MRI, CT, optical coherence tomography, and PET/CT. (4) Conclusion: While MRI remains the gold standard for diagnosing head tumors in Von Hippel-Lindau syndrome, various PET/CT methods show promise as alternative imaging modalities.