von Hippel-Lindau disease: a clinical and scientific review. Eur J Hum Genet. 2011;19:617-623. [PMID: 21386872 DOI: 10.1038/ejhg.2010.175]

Dual Inhibition of HIF-1α and HIF-2α as a Promising Treatment for VHL-Associated Hemangioblastomas: A Pilot Study Using Patient-Derived Primary Cell Cultures

Background: Von Hippel-Lindau (VHL) disease, a hereditary cancer syndrome, is characterized by mutations in the VHL gene, which result in the stabilization of hypoxia-inducible factors (HIF)-1α and -2α, ultimately leading to the development of highly vascularized tumors, such as hemangioblastomas of the central nervous system (CNS-HBs). The standard treatment for these brain tumors is neurosurgical resection. However, multiple surgeries are often necessary due to tumor recurrence, which increases the risk of neurological sequelae. Thus, elucidation of the proliferative behavior of hemangioblastomas (with the aim of identifying biomarkers associated with tumor progression) and the development of pharmacological therapies could reduce the need for repeated surgical interventions and provide alternative treatment options for unresectable CNS-HBs. Belzutifan (Welireg™), a selective HIF-2α inhibitor and the only FDA-approved non-surgical option, has shown limited efficacy in CNS-HBs, highlighting the need for alternative therapeutic strategies. Results: In this study, primary cell cultures were successfully established from CNS-HB tissue samples of VHL patients, achieving a 75% success rate. These cultures were predominantly composed of stromal cells and pericytes. The proliferative patterns of patient-derived HB cell cultures significantly correlated with tumor burden and recurrence in VHL patients. Furthermore, flow cytometry, reverse transcription-PCR, and Western blot analyses revealed marked overexpression of both HIF-1α and HIF-2α isoforms in primary HB cells. In addition, evaluation of the therapeutic potential of acriflavine, a dual HIF-1α/HIF-2α inhibitor, demonstrated reduced HB cells viability, induced G2/M cell cycle arrest, and predominantly triggered necrotic cell death in patient-derived HB cultures. Conclusions: These results suggest that the in vitro proliferative dynamics of HB cell cultures may reflect clinical characteristics associated with CNS-HB progression, potentially serving as indicators to predict tumor development in patients with VHL. Furthermore, our findings support the simultaneous targeting of both HIF-1α and HIF-2α isoforms as a promising non-invasive therapeutic strategy.

Belzutifan for von Hippel-Lindau disease-associated renal cell carcinoma and other neoplasms (LITESPARK-004): 50 months follow-up from a single-arm, phase 2 study

BACKGROUND

Hypoxia-inducible factor-2α inhibitor belzutifan is approved for von Hippel-Lindau disease-associated renal cell carcinoma, CNS haemangioblastomas, and pancreatic neuroendocrine tumours, based on previously published initial results from the LITESPARK-004 study. Updated results are presented here after a median follow-up of nearly 50 months.

METHODS

In this single-arm, phase 2 study, participants were enrolled at 11 centres in Denmark, France, the UK, and the USA. Oral belzutifan 120 mg once daily was given to eligible adults aged 18 years or older with a diagnosis of von Hippel-Lindau disease (based on germline VHL alterations), at least one measurable renal cell carcinoma tumour, no tumour larger than 3 cm that necessitated immediate surgery, no metastatic disease, no previous systemic anticancer treatment, and an Eastern Cooperative Oncology Group performance status score of 0 or 1. The primary endpoint was the proportion of participants with an objective response in von Hippel-Lindau disease-associated renal cell carcinoma per Response Evaluation Criteria in Solid Tumours, version 1.1, determined by an independent review committee, and assessed in all participants who received at least one dose of belzutifan. This ongoing study is no longer recruiting and is registered at ClinicalTrials.gov, NCT03401788.

FINDINGS

Between May 31, 2018, and Mar 29, 2019, 61 participants were enrolled; 36 (59%) were continuing treatment as of April 3, 2023. The median age of all enrolled participants was 41·0 years (IQR 29·0-51·0); 32 (52%) of 61 participants were male and 29 (48%) were female; most were White (n=55; 90%). Median study follow-up was 49·9 months (IQR 48·9-52·2). 41 (67%; 95% CI 54-79) of 61 participants with renal cell carcinoma had an objective response; seven (11%) had a complete response and 34 (56%) a partial response. 13 grade 3 treatment-related adverse events occurred in 11 (18%) participants (anaemia: seven [11%]; fatigue: three [5%]; urinary tract infection: one [2%]; hypoxia: one [2%]; and blister: one [2%]). None of the participants had a grade 4 or 5 treatment-related adverse event. Four (7%) participants had serious treatment-related adverse events (one participant each: anaemia, urinary tract infection, intracranial haemorrhage, and hypoxia).

INTERPRETATION

Updated results support the use of belzutifan as systemic treatment for von Hippel-Lindau disease-associated renal cell carcinoma.

FUNDING

Merck Sharp & Dohme, a subsidiary of Merck & Co, Rahway, NJ, USA; the Intramural Research Program of the National Institutes of Health, National Cancer Institute Center for Cancer Research; and a grant from the National Cancer Institute.

Pheochromocytoma and Paragangliomas: Current Management Strategies

Pheochromocytomas and paragangliomas are rare neuroendocrine tumors with complex clinical presentations and potential for malignancy. This review highlights advancements in biochemical testing, imaging, genetic counseling, and surgical management, which have improved diagnostic accuracy and patient outcomes. Minimally invasive surgical approaches are commonly preferred, but open surgery remains necessary for larger or complex tumors. Emerging treatments in the metastatic stage, such as targeted therapies and radioligand therapy, show promise. However, access to advanced imaging and treatment options varies globally, underscoring the need for multidisciplinary care and further research to optimize management strategies.

Von Hippel-Lindau Disease : A Comprehensive Review of Diagnosis, Genetics, Clinical Challenges, and Surveillance

von Hippel-Lindau (VHL) disease is a genetic condition predisposing individuals to the development of benign and malignant tumors across various organs. This review explores the intricate genetic underpinnings of VHL disease, its clinical manifestations, and the associated malignancy risks. The latest diagnostic criteria, surveillance guidelines, and advancements in therapeutic strategies, including the Food and Drug Administration-approved hypoxia-inducible factor-2α inhibitor, belzutifan, are focused on. Through a multidisciplinary approach, tailored surveillance programs aim to improve patient outcomes while balancing intervention risks. Emerging technologies such as wholebody magnetic resonance imaging and liquid biopsies hold promises for enhancing non-invasive surveillance. This review underscores the significance of ongoing research and interdisciplinary care in managing this complex syndrome.

Genotype-specific neoplastic risk profiles in patients with VHL disease

Hereditary tumor predisposition syndromes pose a challenge for early detection and timely treatment of tumors. In von Hippel-Lindau disease, desirable personalized surveillance programs are lacking due to insufficient data on genotype-specific risk profiles of individual mutations. To describe neoplastic risk profiles for carriers of pathogenic and likely pathogenic VHL germline mutations, our observational study recruited 1,350 participants from 40 centers worldwide. 432 different VHL germline mutations were observed, with p.Asn78Ser, p.Arg161Ter, p.Arg161Gln, p.Arg167Gln, p.Arg167Trp and p.Tyr98His being the six most frequent, occurring in a total of 493 carriers (36.5%) and in ≥30 patients each. Age-related penetrance risks for retinal hemangioblastoma, central nervous system hemangioblastoma, renal cell carcinoma, pancreatic neuroendocrine tumors and pheochromocytoma/paraganglioma in carriers of the most frequent VHL mutations were assessed. In addition, the number of organs affected, the frequency of surgery and the outcome are reported. Pairwise comparisons of the age-dependent tumor penetrance of these six mutations showed that 47 out of 90 pairs were significantly different. The most significant associations were found in p.Tyr98His (n = 19), followed by p.Arg161Ter (n = 10). All pairwise comparisons of mutations affecting different codons showed at least one significant (P < 0.05) difference, except for p.Asn78Ser vs p.Arg161Ter. Thus, tumor risk varied by VHL mutation type and location, but did not differ between the truncating mutation p.Arg161Ter and the missense mutation p.Asn78Ser. Our study demonstrates the importance of mutation-specific phenotype prediction. With appropriate validation, the data have important implications for risk assessment and decision making in tumor prevention for carriers of the respective VHL mutations.

Loss of VHL-mediated pRb regulation promotes clear cell renal cell carcinoma

The von Hippel-Lindau (VHL) tumor suppressor is a substrate-defining component of E3 ubiquitin ligase complexes that target cellular substrates for proteasome-mediated degradation. VHL inactivation by mutation or transcriptional silencing is observed in most sporadic cases of clear cell renal cell carcinoma (ccRCC). VHL loss in ccRCC leads to constitutive stabilization of E3 ligase substrates, including hypoxia inducible factor α (HIFα). HIFα stabilization upon VHL loss is known to contribute to ccRCC development through transactivation of hypoxia-responsive genes. HIF-independent VHL targets have been implicated in oncogenesis, although those mechanisms are less well-defined than for HIFα. Using proximity labeling to identify proteasomal-sensitive VHL interactors, we identified retinoblastoma protein (pRb) as a novel substrate of VHL. Mechanistically, VHL interacts with pRb in a proteasomal-sensitive manner, promoting its ubiquitin-mediated degradation. Concordantly, VHL-inactivation results in pRb hyperstabilization. Functionally, loss of pRb in ccRCC led to increased cell death, transcriptional changes, and loss of oncogenic properties in vitro and in vivo. We also show that downstream transcriptional changes induced by pRb hyperstabilization may contribute to ccRCC tumor development. Together, our findings reveal a novel VHL-related pathway which can be therapeutically targeted to inhibit ccRCC tumor development.

Novel OCT Angiography Features, von Hippel-Lindau Disease Association, and Genetic Characterization of Juxtapapillary Retinal Capillary Hemangiomas

Purpose

To present new clinical features of juxtapapillary retinal capillary hemangiomas (JRCHs), assess the risk of von Hippel-Lindau (VHL) disease, and explore the genotype-phenotype correlations in patients with JRCH.

Methods

Fifty patients with JRCH were included. Multimodal retinal imaging including optical coherence tomography angiography (OCTA), visual acuity, presence of peripheral RCHs, affected lateralities, systemic evaluation for VHL disease, and underlying VHL variants were reviewed.

Results

Of 59 eyes, 48 had classic JRCHs, whereas 11 had atypical JRCHs (type B, if it broke through the inner limiting membrane: 3 eyes; type A, if not: 8 eyes). Compared with atypical type A, which was indolent, type B might warrant surgical interventions. Better final visual acuity (P < 0.0001), fewer peripheral RCHs (P = 0.02), and lower prevalence of large peripheral RCHs (>1.5 mm) (P = 0.027) were observed in eyes with atypical JRCHs than classic JRCHs. VHL was diagnosed clinically in 72% of patients, and 22 VHL variants were identified, including 5 novel variants. Patients with truncating variants had a higher prevalence of atypical JRCHs than those with single amino acid substitution/deletion variants (P = 0.009). Patients with bilateral VHL-JRCHs were more likely to have large peripheral RCHs (P = 0.02) and less likely to harbor β-domain single amino acid substitution/deletion variants (P = 0.066) than those with unilateral VHL-JRCHs.

Conclusions

Atypical JRCHs, with distinctive OCTA characteristics and favorable visual outcomes, are less complicated by peripheral RCHs and more relevant to truncating variant genotypes. JRCH monitoring should incorporate OCTA classification and genotype analysis.

The selection of targeted therapies for relapsed or refractory advanced renal cell carcinoma

INTRODUCTION

Advancements in immunotherapy and angiogenesis-targeted therapies have transformed the upfront treatment of renal cell carcinoma (RCC). However, long-term prognoses for patients with unresectable and metastatic disease often remain limited, with the majority experiencing progression after exposure to front-line therapy. In most cases of relapsed or refractory (R/R) disease after prior exposure to an immune checkpoint inhibitor (ICI), there is no role for ICI-rechallenge. Therefore, treatment of R/R RCC relies on the appropriate selection of therapies targeting growth pathways dependent on vascular endothelial growth factor (VEGF) or hypoxia-inducible factor (HIF).

AREAS COVERED

This review article summarizes the current landscape of targeted therapies for use in second-line or later-line settings for the treatment of clear cell and non-clear cell RCC. Novel therapeutic strategies currently in development are also discussed.

EXPERT OPINION

The treatment of R/R RCC primarily consists of inhibition of VEGF, HIF, and mTOR pathways, and the selection of a specific agent depends on the histologic subtype of the tumor, the prior lines of therapy chosen, and patient co-morbidities. Future tumor-based and circulating biomarker research might one day enable the identification of transcriptional signatures that could predict a response to immune, angiogenesis, or HIF-based therapies.

Characterization of the Pheochromocytoma-Predominant Subgroup of von Hippel-Lindau Disease

OBJECTIVE

To define a classification schema for von Hippel-Lindau (VHL) patients who have a pheochromocytoma predominant phenotyope.

MATERIALS AND METHODS

VHL patients who underwent adrenalectomy with pathology-proven pheochromocytoma at our institution were included. We defined pheochromocytoma-predominant VHL a priori as patients with one or more of the following traits: early onset [age at first pheochromocytoma below the cohort's median age (28.2years)], family history of pheochromocytomas, multiple pheochromocytomas, and paraganglioma(s). Patients with pheochromocytoma-predominant disease were compared to the remaining cohort to determine differences in genotype and phenotype.

RESULTS

One-hundred thirty-nine VHL patients were examined. Preliminary analysis showed that three characteristics (early onset, family history, and multiple pheochromocytomas) were associated. Having paraganglioma(s) did not correlate with the other factors, so it was excluded from the definition of pheochromocytoma-predominant disease. The majority of our patients (110/139, 79%) met the final definition. Pheochromocytoma-predominant patients were less likely to have most additional VHL tumor types, including renal cell carcinoma (P<.001) whereas they were more likely to have missense mutations (P<.001) than the remaining cohort. Overall, pheochromocytoma-predominant patients were most likely to have 0 (P<.001) or 1 (P=.008) extra-adrenal tumor types while non-pheochromocytoma-predominant patients were most likely to have 4 (P=.02) or 5 (P=.02).

CONCLUSION

Pheochromocytoma-predominant VHL patients are phenotypically distinct from their non-pheochromocytoma-predominant counterparts and are significantly less likely to have more than one other VHL manifestation, including renal carcinoma.

DM, Pereira MAA, Tanno FY, Srougi V, Chambo JL, Cordeiro MD, Nahas WC, Hoff AO, Fragoso MCBV, Mendonca BB, Latronico AC, Almeida MQ. Pathogenicity of germline VHL variants is associated with renal cell carcinoma size in von Hippel-Lindau disease

OBJECTIVE

In this study, our aim was to search for new genotype-phenotype correlations in patients with Von Hippel-Lindau (VHL) disease.

SUBJECTS AND METHODS

We retrospectively studied 53 consecutive patients with VHL disease and confirmed genetic diagnoses from 32 relatives.

RESULTS

Most VHL pathogenic or likely pathogenic variants were missense (18 out of 32; 56.25%). The median size of the large carcinoma (RCC) was 3.6 cm (interquartile range, 2.8 to 6.5 cm). Interestingly, the size of the large RCC in patients harboring VHL pathogenic variants (n = 9) was significantly greater than that in patients with VHL likely pathogenic (n = 7) variants (5.4 cm [3.65 to 6.6] vs. 2.9 cm [2.45 to 3.35]; p = 0.008). Moreover, adrenal paraganglioma (PGL) (82.35% vs. 17.65%; p = 0.0001) and pancreatic neuroendocrine tumor (PNET) (81.81% vs. 18.18%; p = 0.007) were associated with missense VHL pathogenic or likely pathogenic variants compared with non-missense defects. In contrast, central nervous system (CNS) hemangioblastomas (HBs) (90.47% vs. 53.12%; p = 0.004), pancreatic cysts (76.19% vs. 28.12%; p = 0.001) and RCCs (57.14% vs. 12.5; p = 0.001) were more common in patients with non-missense VHL variants.

CONCLUSION

VHL pathogenic variants were associated with larger RCCs than were VHL likely pathogenic variants.

Hypoxia-inducible transcription factors: architects of tumorigenesis and targets for anticancer drug discovery

Hypoxia-inducible factors (HIFs) play a pivotal role as master regulators of tumor survival and growth, controlling a wide array of cellular processes in response to hypoxic stress. Clinical data correlates upregulated HIF-1 and HIF-2 levels with an aggressive tumor phenotype and poor patient outcome. Despite extensive validation as a target in cancer, pharmaceutical targeting of HIFs, particularly the interaction between α and βsubunits that forms the active transcription factor, has proved challenging. Nonetheless, many indirect inhibitors of HIFs have been identified, targeting diverse parts of this pathway. Significant strides have also been made in the development of direct inhibitors of HIF-2, exemplified by the FDA approval of Belzutifan for the treatment of metastatic clear cell renal carcinoma. While efforts to target HIF-1 using various therapeutic modalities have shown promise, no clinical candidates have yet emerged. This review aims to provide insights into the intricate and extensive role played by HIFs in cancer, and the ongoing efforts to develop therapeutic agents against this target.

Non-malignant features of cancer predisposition syndromes manifesting in childhood and adolescence: a guide for the general pediatrician

PURPOSE

Cancer predisposition syndromes are genetic disorders that significantly raise the risk of developing malignancies. Although the malignant manifestations of cancer predisposition syndromes are well-studied, recognizing their non-malignant features is crucial for early diagnosis, especially in children and adolescents.

METHODS

A comprehensive literature search was conducted using the PubMed database, focusing on non-malignant manifestations of cancer predisposition syndromes in children and adolescents. Key sources included the Clinical Cancer Research pediatric oncology series and ORPHANET. Studies that described clinical signs and symptoms affecting specific organ systems were included.

RESULTS

Non-malignant dermatological features often serve as early indicators of cancer predisposition syndromes, including café-au-lait spots in Neurofibromatosis Type 1 and facial angiofibromas in Tuberous Sclerosis Complex. Neurological and developmental anomalies such as cerebellar ataxia in ataxia-telangiectasia and intellectual disabilities in neurofibromatosis type 1 and tuberous sclerosis complex are significant indicators. Growth and metabolic anomalies are also notable, including overgrowth in Beckwith-Wiedemann syndrome and growth hormone deficiency in neurofibromatosis Type 1. In addition, facial anomalies, ocular manifestations, hearing issues, and thyroid anomalies are prevalent across various cancer predisposition syndromes. For instance, hearing loss may be significant in neurofibromatosis Type 2, while thyroid nodules are common in PTEN hamartoma tumor syndrome and DICER1 syndrome. Cardiovascular, abdominal, musculoskeletal, pulmonary, genitourinary manifestations, and prenatal deviations further complicate the clinical picture.

CONCLUSIONS

Recognizing non-malignant features of cancer predisposition syndromes is essential for early diagnosis and management. This organ-specific overview furthers awareness among healthcare providers, facilitating timely genetic counseling, surveillance programs, and preventive measures, ultimately improving patient outcomes.

Surgical Management and Prognostic Factors for Endolymphatic Sac Tumor: A Single-Institute Experience with a Systematic Review

OBJECTIVE

To evaluate the clinical features, surgical outcomes, and predictors of progression-free survival (PFS) in patients with endolymphatic sac tumors (ELSTs).

METHODS

This retrospective study analyzed 15 cases from Beijing Tiantan Hospital and 237 from the literature (1988-2023), focusing on patients with pathologically confirmed intracranial or skull ELSTs who had comprehensive treatment and follow-up records. Univariate and multivariate Cox regression analyses were used to identify factors influencing PFS.

RESULTS

Patients from our institute comprised 10 males and 5 females, with an average age of 39.1 years. Among these patients, 86.7% underwent gross total resection (GTR). During the follow-up period, 2 patients (13.3%) were lost to follow-up. After a mean follow-up of 74.9 months, 1 patient experienced recurrence and another died from unrelated causes. A review of the literature identified 237 additional patients, including 134 females (56.5%), with an average age of 39.8 years; 22.8% of these patients had von Hippel-Lindau disease. The GTR rate was 69.2%. After a mean follow-up of 53.2 months, 33 recurrences occurred, and the median PFS was 48 months. In addition, 8 patients died during the follow-up period; none of the deaths was attributed to ELSTs. Multivariate analysis identified GTR (hazard ratio, 0.279; 95% confidence interval, 0.086-0.903; P = 0.033) as a significant protective factor against recurrence among the pooled cases.

CONCLUSIONS

GTR is crucial for improving PFS in patients with ELST, emphasizing the need for advanced surgical techniques and long-term follow-up because of potential recurrences.

New Developments in VHL-Associated Neuroendocrine Neoplasms

PURPOSE OF REVIEW

The purpose of this review is to outline the current knowledge on epidemiology, diagnosis and management of neuroendocrine neoplasms (NENs) that develop in the context of Von Hippel-Lindau (VHL) syndrome.

RECENT FINDINGS

Pancreatic NENs develop in 8-17% of VHL patients (vPNENs) and are mostly multi-focal, cystic and non-functioning. Surgical resection is recommended for vPNENS > 3 cm that exhibit higher metastatic potential or in tumors with short doubling time while in the 20% of cases with metastatic disease the HIF-2 A inhibitor belzutifan is considered a promising option. Pheochromocytomas arising in VHL type 2 are often bilateral and have a noradrenergic phenotype while they are associated with increased risk of recurrence. High-specific activity [131I]-MIBG and sunitinib are the treatment options with the highest level of evidence whereas studies on belzutifan are evolving. Life-long surveillance and management in the context of a multidisciplinary team are suggested to achieve the best clinical outcome.

Novel Von Hippel-Lindau Germline Variants in Iranian Patients with Retinal Capillary Hemangioblastoma

Introduction

The aim of this study was to determine the potential genetic cause of retinal capillary hemangioblastoma (RCH) with symptoms of Von Hippel-Lindau (VHL) disease.

Case Presentations

Three Iranian families (5 RCH patients) with novel variants are included in this study. The VHL variant analysis was performed by the Sanger sequencing technique. Molecular dynamics (MDs) simulations were conducted to analyze conformational changes resulting from variants in VHL protein structure and were compared with that of the native structure. Novel variant sites, including c.511A>C, c.511A>T, and c.514C>T in exon 3 of the VHL gene were identified. According to the American College of Medical Genetics (ACMG) classifications, c.514C>T (p.P172S) and c.511A>C (p.K171Q) are classified as variants of uncertain significance (VUS), and c.511A>T (p.K171*) is classified as a likely pathogenic variant. MD simulations demonstrated overall fluctuations of the proteins structure and a significantly lower degree of flexibility in the α-domain for the variant-encoded VHL protein structure compared to that of the native form.

Conclusion

The structural information and computational analysis of the identified variants are predicted to induce conformational changes that limit the flexibility of protein VHL interaction interface with Elongin B/C, Elongin C/B, and Cullin-2, which are necessary for hypoxia-inducible factor 1-α binding. The genetic variants identified in Iranian patients with RCH may aid in the molecular confirmation of other patients diagnosed with VHL and their at-risk family members. These pioneering results that include detailed structural and functional analysis of a variant's effect on the VHL protein may serve as a model for future studies.

Genotype-phenotype correlation of ocular von Hippel-Lindau disease in Koreans

This scientific report aims to investigate the genotype-phenotype correlations of retinal hemangioblastoma (RH) in von Hippel-Lindau (VHL) disease. The study included 77 patients with genetically confirmed VHL disease who visited an ophthalmology clinic for the evaluation of RH. The presence, location, and size of RH were evaluated, Patients were categorized into three groups based on variants: HIF-1α binding site missense (HM), non-HIF-1α binding site missense (nHM), and truncating (TR) mutations. Fifty-six patients (72.7%) had RH in either eye, and 24 had bilateral RH. Sixteen patients (20.8%) had juxtapapillary RH in either eye. Nine patients had RH ≥ 2.0 disc diameters in size. VHL c.208G>A variant was the most frequent single mutation. Compared with patients having nHM mutations (15 patients) in VHL gene, patients with HM mutations (33 patients) or TR mutations (26 patients) presented a greater number of eyes affected (p = 0.007 and 0.004, respectively), a greater number of RH (p = 0.012 and 0.003, respectively), and more frequent presentation of large RH ≥ 2.0 disc diameters (p = 0.012, and 0.013, respectively). In conclusion, this study provides a deeper understanding of the genetic spectrum of VHL disease in Korean VHL disease and highlights the importance of the location of missense mutations regarding the risk of RH.

Spinal cord hemangioblastomas in von Hippel-Lindau disease

Background

von Hippel-Lindau disease (VHL) is an autosomal dominant familial neoplasia syndrome. The most common manifestation of VHL is central nervous system hemangioblastomas. VHL patients will often develop multiple hemangioblastomas along their craniospinal axis over their lifetime. Spinal cord hemangioblastomas account for nearly half of all nervous system hemangioblastomas in VHL.

Methods

The authors conducted a literature review and summation of available articles on spinal cord hemangioblastomas associated with VHL.

Results

The embryological origins, epidemiology, natural history, surgical outcomes, nonsurgical treatments, and future directions in spinal cord hemangioblastomas are discussed.

Conclusions

Hemangioblastomas in VHL are optimally managed with a multidisciplinary approach that includes surgical resection of symptomatic lesions. Novel treatments are gaining traction, but must be studied further for efficacy and safety.

Innovative solutions? Belzutifan therapy for hemangioblastomas in Von Hippel-Lindau disease: A systematic review and single-arm meta-analysis

BACKGROUND

Von Hippel-Lindau (VHL) disease is a rare autosomal dominant disorder that predisposes patients to develop multiple cysts and tumors, such as hemangioblastomas (HBs) and clear cell renal cell carcinoma (ccRCC), due to mutations in the VHL tumor suppressor gene. While treatment of HBs varies based on their characteristics and has improved patient survival, it still involves high morbidity and mortality, leading to ongoing debates and studies to refine therapy strategies. Recent developments include the emergence of Belzutifan, a novel inhibitor targeting hypoxia-inducible factor 2α (HIF-2α), which has shown promising results in ongoing trials, particularly for patients not immediately requiring surgery.

METHODS

This systematic review and meta-analysis aimed to comprehensively evaluate the efficacy and safety of Belzutifan for treating HBs associated with VHL disease. Search was conducted across Medline, Embase, Cochrane, and Web of Science databases. Statistical Analysis was performed, with proportions and 95 % confidence intervals. Statistical analyses were carried out using R Studio.

RESULTS

Ten studies were selected, comprising 553 patients. The population mean age was 40 (24-65), and 50 % of the population was formed by males. In terms of proportion, 6 analyses were performed: Disease Stability of 31 % [95 %CI:14 %-47 %; I2 = 2 %]; Disease Progression of 2 %[95 %CI:0 %-9 %; I2 = 0 %]; Partial Response of 75 % [95 %CI:54 %-96 %; I2 = 58 %]. Complete response of 1 % [95 %CI:0 %-7 %; I2 = 0 %];and Side effects, anemia 81 % rate [95 % CI:54 %-100 %; I2 = 94 %], and fatigue rate of 79 % [95 % CI:54 %-100 %;I2 = 94 %].

CONCLUSION

Results indicate that Belzutifan effectively stabilizes disease, reduces tumor progression, and achieves significant therapeutic responses, although side effects like anemia and fatigue were noted.

Molecular Genetics of Pheochromocytoma/Paraganglioma

Pheochromocytomas and paragangliomas (PPGL) are neuroendocrine tumors which secrete catecholamines, causing cardiovascular compromise. While isolated tumors and locoregional disease can be treated surgically, treatment options for metastatic disease are limited, and no targeted therapies exist. Approximately 25% of PPGL are causatively associated with germline pathogenic variants, which are known risk factors for multifocal and metastatic PPGL. Knowledge of somatic driver mutations continues to evolve. Molecular classification of PPGL has identified three genomic subtypes: Cluster 1 (pseudohypoxia), Cluster 2 (kinase signaling) and Cluster 3 (Wnt-altered). This review summaries recent studies characterizing the tumor microenvironment, genomic drivers of tumorigenesis and progression, and current research on molecular targets for novel diagnostic and therapeutic strategies in PPGL.

Genetics, Pathophysiology, and Current Challenges in Von Hippel-Lindau Disease Therapeutics

This review article focuses on von Hippel-Lindau (VHL) disease, a rare genetic disorder characterized by the development of tumors and cysts throughout the body. It discusses the following aspects of the disease.

GENETICS

VHL disease is caused by mutations in the VHL tumor suppressor gene located on chromosome 3. These mutations can be inherited or occur spontaneously. This article details the different types of mutations and their associated clinical features.

PATHOPHYSIOLOGY

The underlying cause of VHL disease is the loss of function of the VHL protein (pVHL). This protein normally regulates hypoxia-inducible factors (HIFs), which are involved in cell growth and survival. When pVHL is dysfunctional, HIF levels become elevated, leading to uncontrolled cell growth and tumor formation.

CLINICAL MANIFESTATIONS

VHL disease can affect various organs, including the brain, spinal cord, retina, kidneys, pancreas, and adrenal glands. Symptoms depend on the location and size of the tumors.

DIAGNOSIS

Diagnosis of VHL disease involves a combination of clinical criteria, imaging studies, and genetic testing.

TREATMENT

Treatment options for VHL disease depend on the type and location of the tumors. Surgery is the mainstay of treatment, but other options like radiation therapy may also be used.

CHALLENGES

This article highlights the challenges in VHL disease management, including the lack of effective therapies for some tumor types and the need for better methods to monitor disease progression. In conclusion, we emphasize the importance of ongoing research to develop new and improved treatments for VHL disease.

Advances in Molecular Mechanisms of Kidney Disease: Integrating Renal Tumorigenesis of Hereditary Cancer Syndrome

Renal cell carcinoma (RCC) comprises various histologically distinct subtypes, each characterized by specific genetic alterations, necessitating individualized management and treatment strategies for each subtype. An exhaustive search of the PubMed database was conducted without any filters or restrictions. Inclusion criteria encompassed original English articles focusing on molecular mechanisms of kidney cancer. On the other hand, all non-original articles and articles published in any language other than English were excluded. Hereditary kidney cancer represents 5-8% of all kidney cancer cases and is associated with syndromes such as von Hippel-Lindau syndrome, Birt-Hogg-Dubè syndrome, succinate dehydrogenase-deficient renal cell cancer syndrome, tuberous sclerosis complex, hereditary papillary renal cell carcinoma, fumarate hydratase deficiency syndrome, BAP1 tumor predisposition syndrome, and other uncommon hereditary cancer syndromes. These conditions are characterized by distinct genetic mutations and related extra-renal symptoms. The majority of renal cell carcinoma predispositions stem from loss-of-function mutations in tumor suppressor genes. These mutations promote malignant advancement through the somatic inactivation of the remaining allele. This review aims to elucidate the main molecular mechanisms underlying the pathophysiology of major syndromes associated with renal cell carcinoma. By providing a comprehensive overview, it aims to facilitate early diagnosis and to highlight the principal therapeutic options available.

Metabolomic landscape of renal cell carcinoma in von Hippel-Lindau syndrome in a Chinese cohort

Von Hippel-Lindau (VHL) syndrome is a rare autosomal dominant disorder, where renal cell carcinoma (RCC) serves as a significant cause of mortality. We collected peripheral blood from 61 VHL-RCC patients and 31 healthy individuals, along with 19 paired RCC tumor and adjacent non-malignant samples. Using liquid chromatography-mass spectrometry, we identified 238 plasma and 241 tissue differentially abundant metabolites (DAMs), highlighting key pathways such as arginine and proline metabolism. The top 10 of the 23 DAMs, common to both plasma and tissue, were instrumental in constructing a high-performance diagnostic model. These DAMs demonstrated significant correlations with VHL gene mutation types. Cox regression analysis revealed that plasma levels of N2,N2-dimethylguanosine were associated with the timing of RCC onset in VHL patients, acting as an independent predictive factor. This study enhances diagnostic accuracy for this rare condition and opens new avenues for exploring metabolic mechanisms of the disease and potential therapeutic directions.

Screening and surveillance recommendations for central nervous system hemangioblastomas in pediatric patients with Von Hippel-Lindau disease

PURPOSE

Von Hippel-Lindau (VHL) disease is an autosomal-dominantly inherited tumor predisposition syndrome. One of the most common tumors are central nervous system (CNS) hemangioblastomas. Recommendations on the initiation and continuation of the screening and surveillance program for CNS tumors in pediatric VHL patients are based on small case series and thus low evidence level. To derive more robust screening recommendations, we report on the largest monocentric pediatric cohort of VHL patients.

METHODS

We performed a retrospective analysis on a pediatric cohort of 99 VHL patients consulted at our VHL center from 1992 to 2023. Clinical, surgical, genetic, and imaging data were collected and statistically analyzed.

RESULTS

42 patients (50% male) developed CNS hemangioblastomas, of whom 18 patients (56% male) underwent hemangioblastoma surgery (mean age at first surgery: 14.9 ± 1.9 years; range 10.2-17). The first asymptomatic patient was operated on at the age of 13.2 years due to tumor progress. Truncating VHL mutation carriers had a significantly higher manifestation rate (HR = 3.7, 95% CI: 1.9-7.4, p < 0.0001) and surgery rate (HR = 3.3, 95% CI: 1.2-8.9, p = 0.02) compared with missense mutation carriers.

CONCLUSION

We recommend starting MRI imaging at the age of 12 years with examination intervals every (1-) 2 years depending on CNS involvement. Special attention should be paid to patients with truncating variants. Affected families should be educated regularly on potential tumor-associated symptoms to enable timely MRI imaging and eventually intervention, as CNS hemangioblastoma may develop before screening begins.

GERMAN CLINICAL TRIALS REGISTER REGISTRATION NUMBER

DRKS00029553, date of registration 08/16/2022, retrospectively registered.

Saturation genome editing maps the functional spectrum of pathogenic VHL alleles

To maximize the impact of precision medicine approaches, it is critical to identify genetic variants underlying disease and to accurately quantify their functional effects. A gene exemplifying the challenge of variant interpretation is the von Hippel-Lindautumor suppressor (VHL). VHL encodes an E3 ubiquitin ligase that regulates the cellular response to hypoxia. Germline pathogenic variants in VHL predispose patients to tumors including clear cell renal cell carcinoma (ccRCC) and pheochromocytoma, and somatic VHL mutations are frequently observed in sporadic renal cancer. Here we optimize and apply saturation genome editing to assay nearly all possible single-nucleotide variants (SNVs) across VHL's coding sequence. To delineate mechanisms, we quantify mRNA dosage effects and compare functional effects in isogenic cell lines. Function scores for 2,268 VHL SNVs identify a core set of pathogenic alleles driving ccRCC with perfect accuracy, inform differential risk across tumor types and reveal new mechanisms by which variants impact function. These results have immediate utility for classifying VHL variants encountered clinically and illustrate how precise functional measurements can resolve pleiotropic and dosage-dependent genotype-phenotype relationships across complete genes.

Validation and Evaluation of 5 Scoring Systems for Predicting Metastatic Risk in Pheochromocytoma and Paraganglioma

Currently, 5 scoring systems have been proposed in the literature for predicting metastatic risk in pheochromocytoma and paraganglioma (PPGL): Pheochromocytoma of the Adrenal Gland Scaled Score (PASS), Grading System for Adrenal Pheochromocytoma and Paraganglioma (GAPP), Composite Pheochromocytoma/paraganglioma Prognostic Score (COPPS), Age, Size, Extra-adrenal location, Secretion type (ASES) score, and Size, Genetic, Age, and PASS (SGAP) model. To validate and evaluate these 5 scoring systems, we conducted a retrospective review of cases diagnosed as PPGL at the Department of Pathology, West China Hospital of Sichuan University, between January 2012 and December 2019. A total of 185 PPGL cases were included, comprising 35 cases with metastasis and 150 cases remained metastasis-free for over 8 years after surgery. The criteria of the 5 scoring systems were used for scoring and risk classification. The predictive performance of the 5 scoring systems was validated, compared, and evaluated using concordance index (C-index) and decision curve analysis (DCA). The C-indices for PASS, GAPP, and SGAP were 0.600, 0.547, and 0.547, respectively, indicating low discriminative ability. In contrast, COPPS and ASES had C-indices of 0.740 and 0.706, respectively, indicating better discriminative performance. DCA also showed that the predictive capability of COPPS was superior to that of ASES, with both outperformed PASS, while PASS had better predictive ability than GAPP and SGAP. Our analysis indicated that pathology-based scoring systems cannot accurately predict metastatic risk of PPGL. Establishing a precise prediction system requires integrating clinical, pathologic, and molecular information, using a scientific methodology for predictive factor selection and weight assessment.

Single Stage Bilateral Adrenalectomy (Cortical-Sparing) and Pancreatectomy (Corpus-Sparing) in a Patient with Von Hippel-Lindau Disease

Von Hippel-Lindau (VHL) disease is an autosomal dominant syndrome and affects many organs. We aim to report an adult patient with VHL disease having bilateral adrenal pheochromocytoma and multiple neuroendocrine tumors of the pancreas who was successfully treated with simultaneous function-preserving adrenalectomy and pancreatectomy. A 27-year-old woman was admitted to hospital with hypertension. The computed tomography of the abdomen revealed a solid tumor in both adrenal glands with the sizes of 12x7 cm on the right and 4x4 cm on the left. She also had two pancreatic solid masses in the head and three in the tail with varying sizes. The laboratory tests are all within normal limits except elevated 24-hour urinary metanephrine and normetanephrine. I-123 MIBG scanning showed increased uptake in both adrenal glands. Fine needle aspiration biopsy of the tumor on head of pancreas via endoscopic ultrasonography showed neuroendocrine tumor. Those findings were compatible with bilateral pheochromocytoma and multiple pancreatic neuroendocrine tumors and genetic tests revealed the mutation which confirmed the diagnosis of VHL disease. After suppression with alpha-1 inhibitor, right total, left cortical-sparing adrenalectomy, Whipple procedure for the pancreatic head lesions and spleen-preserving distal pancreatectomy were performed and pancreatic corpus was preserved. This case showed that multiple function-preserving procedures can be safely performed with oncological principles in patients with VHL disease.

Late-Onset Manifestations of Von Hippel-Lindau Syndrome: A Case Report

Von Hippel-Lindau (VHL) syndrome is characterized by a range of tumors including phaeochromocytomas, pancreatic adenomas, cerebellar haemangioblastomas, and renal cell carcinomas. A 50-year-old male presented with a three-week history of headache. Additionally, the patient exhibited signs of hypertension. Ultrasonography (USG) abdomen and pelvis showed a solid mass lesion in the left adrenal gland, iso-echoic to the renal cortex. On contrast-enhanced computed tomography (CECT) of the brain, a well-defined solid cystic lesion was seen in the left posterior cerebellar hemisphere. Small nodular enhancing lesions were seen in the right cerebellar hemisphere. On further imaging with MRI brain contrast, the lesions in the cerebellum were diagnosed as multifocal hemangioblastomas. Laboratory investigations revealed elevated urinary metanephrines and normetanephrine, suggesting pheochromocytoma. Based on radiological and biochemical investigations, with the features of cerebellar haemangioblastomas and pheochromocytoma, a diagnosis of VHL syndrome was made.

CT-derived radiomics predict the growth rate of renal tumours in von Hippel-Lindau syndrome

AIM

To predict renal tumour growth patterns in von Hippel-Lindau syndrome by utilising radiomic features to assist in developing personalised surveillance plans leading to better patient outcomes.

MATERIALS AND METHODS

The study evaluated 78 renal tumours in 55 patients with histopathologically-confirmed clear cell renal cell carcinomas (ccRCCs), which were segmented and radiomics were extracted. Volumetric doubling time (VDT) classified the tumours into fast-growing (VDT <365 days) or slow-growing (VDT ≥365 days). Volumetric and diametric growth analyses were compared between the groups. Multiple logistic regression and random forest classifiers were used to select the best features and models based on their correlation and predictability of VDT.

RESULTS

Fifty-five patients (mean age 42.2 ± 12.2 years, 27 men) with a mean time difference of 3.8 ± 2 years between the baseline and preoperative scans were studied. Twenty-five tumours were fast-growing (low VDT, i.e., <365 days), and 53 tumours were slow-growing (high VDT, i.e., ≥365 days). The median volumetric and diametric growth rates were 1.71 cm3/year and 0.31 cm/year. The best feature using univariate analysis was wavelet-HLL_glcm_ldmn (area under the receiver operating characteristic [ROC] curve [AUC] of 0.80, p<0.0001), and with the random forest classifier, it was log-sigma-0-5-mm-3D_glszm_ZonePercentage (AUC: 79). The AUC of the ROC curves using multiple logistic regression was 0.74, and with the random forest classifier was 0.73.

CONCLUSION

Radiomic features correlated with VDT and were able to predict the growth pattern of renal tumours in patients with VHL syndrome.

Belzutifan for von Hippel-Lindau Disease: Pancreatic Lesion Population of the Phase 2 LITESPARK-004 Study

PURPOSE

Primary analysis of the ongoing, single-arm, phase 2 LITESPARK-004 study (NCT03401788) showed clinically meaningful antitumor activity in von Hippel-Lindau (VHL) disease-associated renal cell carcinoma (RCC) and other neoplasms with belzutifan treatment. We describe results of belzutifan treatment for VHL disease-associated pancreatic lesions [pancreatic neuroendocrine tumors (pNET) and serous cystadenomas].

PATIENTS AND METHODS

Adults with VHL diagnosis based on germline VHL alteration, ≥1 measurable RCC tumor, no renal tumor >3 cm or other VHL neoplasm requiring immediate surgery, Eastern Cooperative Oncology Group performance status of 0 or 1, and no prior systemic anticancer treatment received belzutifan 120 mg once daily. End points included objective response rate (ORR), duration of response (DOR), progression-free survival (PFS), and linear growth rate (LGR) in all pancreatic lesions and pNETs per RECIST version 1.1 by independent review committee, and safety.

RESULTS

All 61 enrolled patients (100%) had ≥1 pancreatic lesion and 22 (36%) had ≥1 pNET measurable at baseline. Median follow-up was 37.8 months (range, 36.1-46.1). ORR was 84% [51/61; 17 complete responses (CR)] in pancreatic lesions and 91% (20/22; 7 CRs) in pNETs. Median DOR and median PFS were not reached in pancreatic lesions or pNETs. After starting treatment, median LGR for pNETs was -4.2 mm per year (range, -7.9 to -0.8). Eleven patients (18%) had ≥1 grade 3 treatment-related adverse event (AE). No grade 4 or 5 treatment-related AEs occurred.

CONCLUSIONS

Belzutifan continued to show robust activity and manageable safety in VHL disease-associated pNETs.

Kidney scoring surveillance: predictive machine learning models for clear cell renal cell carcinoma growth using MRI

INTRODUCTION

Classification of clear cell renal cell carcinoma (ccRCC) growth rates in patients with Von Hippel-Lindau (VHL) syndrome has several ramifications for tumor monitoring and surgical planning. Using two separate machine-learning algorithms, we sought to produce models to predict ccRCC growth rate classes based on qualitative MRI-derived characteristics.

MATERIAL AND METHODS

We used a prospectively maintained database of patients with VHL who underwent surgical resection for ccRCC between January 2015 and June 2022. We employed a threshold growth rate of 0.5 cm per year to categorize ccRCC tumors into two distinct groups-'slow-growing' and 'fast-growing'. Utilizing a questionnaire of qualitative imaging features, two radiologists assessed each lesion on different MRI sequences. Two machine-learning models, a stacked ensemble technique and a decision tree algorithm, were used to predict the tumor growth rate classes. Positive predictive value (PPV), sensitivity, and F1-score were used to evaluate the performance of the models.

RESULTS

This study comprises 55 patients with VHL with 128 ccRCC tumors. Patients' median age was 48 years, and 28 patients were males. Each patient had an average of two tumors, with a median size of 2.1 cm and a median growth rate of 0.35 cm/year. The overall performance of the stacked and DT model had 0.77 ± 0.05 and 0.71 ± 0.06 accuracies, respectively. The best stacked model achieved a PPV of 0.92, a sensitivity of 0.91, and an F1-score of 0.90.

CONCLUSION

This study provides valuable insight into the potential of machine-learning analysis for the determination of renal tumor growth rate in patients with VHL. This finding could be utilized as an assistive tool for the individualized screening and follow-up of this population.

Update of the UMD-VHL database: classification of 164 challenging variants based on genotype-phenotype correlation among 605 entries

BACKGROUND

The von Hippel-Lindau (VHL) disease is a hereditary tumour syndrome caused by germline mutations in VHL tumour suppressor gene. The identification of VHL variants requires accurate classification which has an impact on patient management and genetic counselling.

METHODS

The TENGEN (French oncogenetics network of neuroendocrine tumors) and PREDIR (French National Cancer Institute network for Inherited predispositions to kidney cancer) networks have collected VHL genetic variants and clinical characteristics of all VHL-suspected patients analysed from 2003 to 2021 by one of the nine laboratories performing VHL genetic testing in France. Identified variants were registered in a locus-specific database, the Universal Mutation Database-VHL database (http://www.umd.be/VHL/).

RESULTS

Here we report the expert classification of 164 variants, including all missense variants (n=124), all difficult interpretation variants (n=40) and their associated phenotypes. After initial American College of Medical Genetics classification, first-round classification was performed by the VHL expert group followed by a second round for discordant and ambiguous cases. Overall, the VHL experts modified the classification of 87 variants including 30 variants of uncertain significance that were as (likely)pathogenic variants for 19, and as likely benign for 11.

CONCLUSION

Consequently, this work has allowed the diagnosis and influenced the genetic counselling of 45 VHL-suspected families and can benefit to the worldwide VHL community, through this review.

Belzutifan-induced regression of retinal capillary hemangioblastoma: A case-series

Purpose

To report a series of three patients with von Hippel-Lindau (VHL) disease who demonstrated regression of their retinal hemangioblastomas (RH) using belzutifan in conjunction with photocoagulation therapy.

Observations

Patient 1, a 23-year-old female, presented with multiple RHs in her right eye (OD) that were lasered. Her left eye (OS) revealed a large inferotemporal RH that measured approximately 2.1 mm2. Systemic belzutifan was administered. Four months after initiation of treatment, the lesion regressed to 1.4 mm2, but belzutifan was not well-tolerated and was discontinued due to side effects. At the date of belzutifan discontinuation, the lesion measured about 1.1 mm2. Focal laser photocoagulation was applied. The lesion regressed to around 0.6 mm2. Two additional laser treatments were applied one month later. On the most recent follow-up, the lesion was completely fibrosed.Patient 2, a 32-year-old male, presented with one RH OD and two RHs OS. Belzutifan was administered for one month before the patient began experiencing side effects of the medication. Consequently, the dose of belzutifan was decreased. After one month with the lowered dose, laser coagulation was applied to OS. In the most recent follow-up, five months after the initial presentation, the lesions remain less vascularized and reduced in size.Patient 3, is a 44-year-old male with a large RH OD. Following seven months of belzutifan daily, there was a significant reduction in the RH size.

Conclusions

Belzutifan, a hypoxia-inducible factor inhibitor, is an FDA-approved medication for VHL disease associated with renal cell carcinoma, central nervous system hemangioblastomas, or pancreatic neuroendocrine tumors that do not require immediate surgical resection. Because of the high incidence of VHL-associated RHs, adjuvant laser photocoagulation therapy when belzutifan is suspended or withheld can allow for the regression of large lesions. In this case series, we also propose a reproducible and technically simple method to measure RH lesions size, using Optos fundus imaging.

State of the Science and Ethical Considerations for Preimplantation Genetic Testing for Monogenic Cystic Kidney Diseases and Ciliopathies

There is a broad phenotypic spectrum of monogenic polycystic kidney diseases (PKDs). These disorders often involve cilia-related genes and lead to the development of fluid-filled cysts and eventual kidney function decline and failure. Preimplantation genetic testing for monogenic (PGT-M) disorders has moved into the clinical realm. It allows prospective parents to avoid passing on heritable diseases to their children, including monogenic PKD. The PGT-M process involves embryo generation through in vitro fertilization, with subsequent testing of embryos and selective transfer of those that do not harbor the specific disease-causing variant(s). There is a growing body of literature supporting the success of PGT-M for autosomal-dominant and autosomal-recessive PKD, although with important technical limitations in some cases. This technology can be applied to many other types of monogenic PKD and ciliopathies despite the lack of existing reports in the literature. PGT-M for monogenic PKD, like other forms of assisted reproductive technology, raises important ethical questions. When considering PGT-M for kidney diseases, as well as the potential to avoid disease in future generations, there are regulatory and ethical considerations. These include limited government regulation and unstandardized consent processes, potential technical errors, high cost and equity concerns, risks associated with pregnancy for mothers with kidney disease, and the impact on all involved in the process, including the children who were made possible with this technology.

Novel Approaches with HIF-2α Targeted Therapies in Metastatic Renal Cell Carcinoma

Germline inactivation of the Von Hippel-Lindau (VHL) tumor suppressor is the defining hallmark in hereditary VHL disease and VHL-associated renal cell carcinoma (RCC). However, somatic VHL mutations are also observed in patients with sporadic RCC. Loss of function VHL mutations result in constitutive activation of hypoxia-inducible factor-2 alpha (HIF-2α), which leads to increased expression of HIF target genes that promote angiogenesis and tumor growth. As of 2023, belzutifan is currently the only approved HIF-2α inhibitor for both VHL-associated and sporadic metastatic RCC (mRCC). However, there is potential for resistance with HIF-2α inhibitors which warrants novel HIF-2α-targeting strategies. In this review, we discuss the potential resistance mechanisms with belzutifan and current clinical trials evaluating novel combinations of belzutifan with other targeted therapies and immune checkpoint inhibitors which may enhance the efficacy of HIF-2α targeting. Lastly, we also discuss newer generation HIF-2α inhibitors that are currently under early investigation and outline future directions and challenges with HIF-2α inhibitors for mRCC.

Characterizing and predicting ccRCC-causing missense mutations in Von Hippel-Lindau disease

BACKGROUND

Mutations within the Von Hippel-Lindau (VHL) tumor suppressor gene are known to cause VHL disease, which is characterized by the formation of cysts and tumors in multiple organs of the body, particularly clear cell renal cell carcinoma (ccRCC). A major challenge in clinical practice is determining tumor risk from a given mutation in the VHL gene. Previous efforts have been hindered by limited available clinical data and technological constraints.

METHODS

To overcome this, we initially manually curated the largest set of clinically validated VHL mutations to date, enabling a robust assessment of existing predictive tools on an independent test set. Additionally, we comprehensively characterized the effects of mutations within VHL using in silico biophysical tools describing changes in protein stability, dynamics and affinity to binding partners to provide insights into the structure-phenotype relationship. These descriptive properties were used as molecular features for the construction of a machine learning model, designed to predict the risk of ccRCC development as a result of a VHL missense mutation.

RESULTS

Analysis of our model showed an accuracy of 0.81 in the identification of ccRCC-causing missense mutations, and a Matthew's Correlation Coefficient of 0.44 on a non-redundant blind test, a significant improvement in comparison to the previous available approaches.

CONCLUSION

This work highlights the power of using protein 3D structure to fully explore the range of molecular and functional consequences of genomic variants. We believe this optimized model will better enable its clinical implementation and assist guiding patient risk stratification and management.

von Hippel-Lindau disease-related neoplasia with an emphasis on renal manifestations

von Hippel-Lindau (VHL) disease is characterized by biallelic inactivation of the VHL gene leading to abnormal or absent VHL protein function, and constitutive activation of hypoxia-inducible factors (HIF) that leads to pro-tumorigenic signaling. Individuals with VHL disease develop numerous cysts and tumors involving multiple organs including the kidneys, central nervous system, endolymphatic sac, lungs, pancreatobiliary system, adrenal glands, epididymis, and/or broad ligament. On histologic examination, these lesions show morphologic overlap as they are frequently characterized by cells with clear cytoplasm and prominent vascularity. In addition to distinguishing non-renal tumors from metastatic clear cell renal cell carcinoma, understanding site-specific histopathologic and immunophenotypic features of these tumors has several applications. This includes distinguishing VHL-related tumors from those that arise sporadically and lack VHL gene alterations, guiding further genetic workup, and helping distinguish between different genetic predisposition syndromes. In this context, immunohistochemical studies for markers such as paired box 8 (PAX-8), carbonic anhydrase 9 (CA9), and glucose transporter 1 (GLUT-1) have an important role in routine clinical practice and represent cost-effective diagnostic tools. The recent development of targeted therapeutics directed against HIF-mediated signaling represents a significant milestone in the management of VHL disease and highlights the importance of accurately diagnosing and characterizing the wide spectrum of VHL disease-associated lesions.

[The development of innovative therapeutic drugs targeting hypoxia responses]

The 2019 Nobel Prize in Physiology or Medicine was awarded to Dr. William G. Kaelin Jr, Dr. Peter J. Ratcliffe, and Dr. Gregg L. Semenza for their elucidation of new physiological mechanisms "How cells sense and adapt to oxygen availability". Moreover, two different drugs, HIF-PH inhibitors and HIF-2 inhibitors were also developed based on the discovery. Interestingly, those three doctors have different backgrounds as a medical oncologist, a nephrologist, and a pediatrician, respectively. They have started the research based on their own unique perspectives and eventually merged as "the elucidation of the response mechanism of living organisms to hypoxic environments". In this review, we will explain how the translational research that has begun to solve unmet clinical needs successfully contributed to the development of innovative therapeutic drugs.

Mechanisms of tyrosine kinase inhibitor resistance in renal cell carcinoma

Renal cell carcinoma (RCC), the most prevalent type of kidney cancer, is a significant cause of cancer morbidity and mortality worldwide. Antiangiogenic tyrosine kinase inhibitors (TKIs), in combination with immune checkpoint inhibitors (ICIs), are among the first-line treatment options for patients with advanced RCC. These therapies target the vascular endothelial growth factor receptor (VEGFR) tyrosine kinase pathway and other kinases crucial to cancer proliferation, survival, and metastasis. TKIs have yielded substantial improvements in progression-free survival (PFS) and overall survival (OS) for patients with advanced RCC. However, nearly all patients eventually progress on these drugs as resistance develops. This review provides an overview of TKI resistance in RCC and explores different mechanisms of resistance, including upregulation of alternative proangiogenic pathways, epithelial-mesenchymal transition (EMT), decreased intracellular drug concentrations due to efflux pumps and lysosomal sequestration, alterations in the tumor microenvironment including bone marrow-derived cells (BMDCs) and tumor-associated fibroblasts (TAFs), and genetic factors such as single nucleotide polymorphisms (SNPs). A comprehensive understanding of these mechanisms opens the door to the development of innovative therapeutic approaches that can effectively overcome TKI resistance, thereby improving outcomes for patients with advanced RCC.

Sunitinib Treatment of VHL C162F Cells Slows Down Proliferation and Healing Ability via Downregulation of ZHX2 and Confers a Mesenchymal Phenotype

von Hippel-Lindau (VHL) disease, due to mutations of the tumor suppressor VHL gene, is a rare hereditary syndrome with a high risk of developing clear cell renal cell carcinoma (ccRCC). We asked whether the VHL-C162F mutation interferes with proliferation, migration, healing and forming colony ability by using wild-type VHL (WT VHL) and VHL-C162F reconstituted cells. We then analyzed the in vitro impact of the sunitinib treatment on VHL-C162F cells. We showed that VHL-C162F mutations have no impact on cell morphology, colony formation and migration ability but confer a significant higher healing ability than in WT VHL cells. RNA sequencing analysis revealed that VHL-C162F mutation upregulates genes involved in hypoxia and epithelial mesenchymal transition (EMT) pathways by comparison with VHL WT cells. We next showed a decrease in healing ability in VHL-C162F cells depleting on ZHX2, an oncogenic driver of ccRCC, highlighting the potential involvement of ZHX2 in aggressiveness of the VHL-C162F cells. Moreover, we found that sunitinib treatment inhibits ZHX2 expression and induces a reduced proliferation correlating with downregulation of P-ERK. Sunitinib treatment also conferred a more mesenchymal profile to VHL-C162F cells with significant downregulation of E-cadherin and upregulation of N-cadherin, Slug and AXL. Sunitinib therapy may therefore promote disease progression in VHL-C162F patients.

Outcomes of and indications for renal transplantation in patients with von Hippel Lindau disease

INTRODUCTION AND OBJECTIVE

Von Hippel-Lindau (VHL) is a hereditary cancer syndrome characterized by bilateral, multifocal renal masses. The cumulative impact of extirpative surgery can depreciate renal function and render patients anephric. In the larger end-stage renal disease population, renal transplant offers both excellent quality of life and functional renal replacement. This case control study aims to examine and compare oncologic and functional outcomes of patients who have undergone renal transplant as renal replacement therapy (RRT) to those who remain anephric.

METHODS

Patient charts were retrospectively reviewed of patients with germline testing confirmed VHL between 1980 and 2022 for transplant, all prior surgical history (within and outside the NCI), renal function and graft outcomes. Overall survival (OS) was determined from years after radical nephrectomy, and graft time was defined as years of graft function from initial transplant until failure or patient death. Graft survival was determined as time between transplant(s) to last follow up. Kaplan-Meier analysis was conducted to compare graft times of anephric VHL patients to those with transplanted kidneys.

RESULTS

A total of 23 VHLD patients were identified as either anephric or candidates for transplant. Out of this cohort, 11 total VHLD received 12 total kidney grafts. Median wait time from nephrectomy to transplant was 22.6 months (IQR: 1.02-40.25 months). Median age at transplant was 32 years (IQR: 23-54 years). OS at 5 and 10 years of anephric patients who did not receive a transplant was 33% and 16.7%, respectively. OS rates of the transplant cohort at 10, 15, and 20 years were 91%, 78%, and 58% years, respectively. Median graft time was 161 months (IQR: 56-214 months). Graft survival at 10, 15, and 20 years was 69.8%, 69.8%, and 26.2%, respectively.

CONCLUSIONS

We demonstrate that transplant recipients have decreased mortality with no difference in cancer recurrence compared to those who do not receive renal transplant for RRT. This data can aid in informing providers of the optimal window for early RRT planning in VHL, while also improving patient counseling.

A nonsense mutation in VHL causing Von Hippel-Lindau syndrome in a large Chinese family-a genetic study of familial neoplastic disease

Von Hippel-Lindau (VHL) syndrome is a multi-organ neoplastic disease characterized by highly vascular and cystic tumors in the central nervous system (CNS), retina, and visceral lesions, which are mainly caused by germline mutations in VHL. We aimed to detect novel mutations in VHL gene in families with VHL. Here, a large consanguineous four-generation family with variant phenotypes of VHL syndrome was recruited, and its molecular genetics were tested via Sanger sequencing. And various tools and databases were used to predict the variant pathogenicity, frequency, and protein function. Genetic investigation detected a c.351G > A nonsense mutation in VHL that altered the downstream reading frame and created a premature TGA stop signal, resulting in severely truncated pVHL (p.Trp117Ter). This mutation is absent from most public databases, and functional prediction bioinformatic tools demonstrated that this residue is conserved and that this variant is highly likely to be deleterious. The c.315G > A nonsense mutation in VHL is the causal mutation of this kindred that may lead to clear familial aggregation of VHL syndrome because of the dysfunction of the truncated pVHL.

The potential of targeting cuproptosis in the treatment of kidney renal clear cell carcinoma

Renal cell carcinoma (RCC) is one of the top ten malignancies and tumor-related causes of death worldwide. The most common histologic subtype is kidney renal clear cell carcinoma (KIRC), accounting for approximately 75% of all RCC cases. Early resection is considered the basic treatment for patients with KIRC. However, approximately 30% of these patients experience recurrence post-operation. Cuproptosis, an autonomous mechanism for controlling cell death, encompasses various molecular mechanisms and multiple cellular metabolic pathways. These pathways mainly include copper metabolic signaling pathways, mitochondrial metabolism signaling pathways, and lipoic acid pathway signaling pathways. Recent evidence shows that cuproptosis is identified as a key cell death modality that plays a meaningful role in tumor progression. However, there is no published systematic review that summarizes the correlation between cuproptosis and KIRC, despite the fact that investigations on cuproptosis and the pathogenesis of KIRC have increased in past years. Researchers have discovered that exogenous copper infusion accelerates the dysfunction of mitochondrial dysfunction and suppresses KIRC cells by inducing cuproptosis. The levels of tricarboxylic acid cycle proteins, lipoic acid protein, copper, and ferredoxin 1 (FDX1) were dysregulated in KIRC cells, and the prognosis of patients with high FDX1 expression is better than that of patients with low expression. Cuproptosis played an indispensable role in the regulation of tumor microenvironment features, tumor progression, and long-term prognosis of KIRC. In this review, we summarized the systemic and cellular metabolic processes of copper and the copper-related signaling pathways, highlighting the potential targets related to cuproptosis for KIRC treatment.

The outcome of central nervous system hemangioblastomas in Von Hippel-Lindau (VHL) disease treated with belzutifan: a single-institution retrospective experience

PURPOSE

Belzutifan is a Hypoxia Inducible Factor 2-alpha inhibitor approved in 2021 by the FDA for the treatment of renal cell carcinoma (RCC) in patients with Von-Hippel Landau (VHL) disease. These patients can also present with central nervous system (CNS) hemangioblastomas (HBs). We aim to study the effectiveness and adverse effects of belzutifan for CNS HBs, by reporting our preliminary institutional experience.

METHODS

We present a series of VHL patients with CNS HBs undergoing treatment with belzutifan for RCC. All the included patients met the RECIST inclusion criteria. The clinical and radiological outcome measures included: Objective response rate (ORR), time-to-response (TTR), adverse events (AE), and patient response. Patient response was classified as partial response (PR), complete response (CR), progressive disease (PD), or stable disease (SD).

RESULTS

Seven patients with 25 HBs were included in our study. A belzutifan dose of 120 mg/day PO was administered for a median of 13 months (range 10-17). Median follow up time was 15 months (range 10-24). An ORR of 71% was observed. The median TTR was 5 months (range: 1-10). None of the patients showed CR, while 5 patients (71.4%) showed PR and 2 (28.5%) showed SD. Among patients with SD the maximum tumor response was 20% [increase/decrease] of the lesion diameter. All the patients experienced decreased hemoglobin concentration, fatigue, and dizziness. None of the patients experienced severe anemia (grade 3-4 CTCAE).

CONCLUSION

Belzutifan appears to be an effective and safe treatment for CNS hemangioblastoma in VHL patients. Further clinical trials to assess the long-term effectiveness of the medication are required.

Preoperative Renal Parenchyma Volume as a Predictor of Kidney Function Following Nephrectomy of Complex Renal Masses

Background

The von Hippel-Lindau disease (VHL) is a hereditary cancer syndrome with multifocal, bilateral cysts and solid tumors of the kidney. Surgical management may include multiple extirpative surgeries, which ultimately results in parenchymal volume loss and subsequent renal function decline. Recent studies have utilized parenchyma volume as an estimate of renal function prior to surgery for renal cell carcinoma; however, it is not yet validated for surgically altered kidneys with multifocal masses and complex cysts such as are present in VHL.

Objective

We sought to validate a magnetic resonance imaging (MRI)-based volumetric analysis with mercaptoacetyltriglycine (MAG-3) renogram and postoperative renal function.

Design setting and participants

We identified patients undergoing renal surgery at the National Cancer Institute from 2015 to 2020 with preoperative MRI. Renal tumors, cysts, and parenchyma of the operated kidney were segmented manually using ITK-SNAP software.

Outcome measurements and statistical analysis

Serum creatinine and urinalysis were assessed preoperatively, and at 3- and 12-mo follow-up time points. Estimated glomerular filtration rate (eGFR) was calculated using serum creatinine-based CKD-EPI 2021 equation. A statistical analysis was conducted on R Studio version 4.1.1.

Results and limitations

Preoperative MRI scans of 113 VHL patients (56% male, median age 48 yr) were evaluated between 2015 and 2021. Twelve (10.6%) patients had a solitary kidney at the time of surgery; 59 (52%) patients had at least one previous partial nephrectomy on the renal unit. Patients had a median of three (interquartile range [IQR]: 2-5) tumors and five (IQR: 0-13) cysts per kidney on imaging. The median preoperative GFR was 70 ml/min/1.73 m2 (IQR: 58-89). Preoperative split renal function derived from MAG-3 studies and MRI split renal volume were significantly correlated (r = 0.848, p < 0.001). On the multivariable analysis, total preoperative parenchymal volume, solitary kidney, and preoperative eGFR were significant independent predictors of 12-mo eGFR. When only considering patients with two kidneys undergoing partial nephrectomy, preoperative parenchymal volume and eGFR remained significant predictors of 12-mo eGFR.

Conclusions

A parenchyma volume analysis on preoperative MRI correlates well with renogram split function and can predict long-term renal function with added benefit of anatomic detail and ease of application.

Patient summary

Prior to kidney surgery, it is important to understand the contribution of each kidney to overall kidney function. Nuclear medicine scans are currently used to measure split kidney function. We demonstrated that kidney volumes on preoperative magnetic resonance imaging can also be used to estimate split kidney function before surgery, while also providing essential details of tumor and kidney anatomy.

Neurocutaneous Disorders in Pregnancy

Importance

Neurocutaneous disorders have significant implications for care of the pregnant patient. As neurocutaneous disorders are uncommon, obstetricians may be unfamiliar with these disorders and with recommendations for appropriate care of this population.

Objective

This review aims to summarize existing literature on the interaction between neurocutaneous disorders and pregnancy and to provide a guide for physicians caring for an affected patient.

Evidence Acquisition

A PubMed, MEDLINE, and Google Scholar search was carried out with a broad range of combinations of the medical subject headings (MeSH) terms "pregnancy," "Sturge -Weber," "Neurofibromatosis Type 1," "neurofibromatosis type 2," "von Hippel Lindau," "Tuberous Sclerosis," "neurocutaneous disorder," "treatment," "congenital malformations," "neurodevelopmental defects," "miscarriage," "breastfeeding," "autoimmune," "pathophysiology," and "management." References of included articles were searched to identify any articles that may have been missed after the above method was used.

Results

Neurocutaneous disorders are associated with increased pregnancy-associated maternal and fetal/neonatal morbidity, largely surrounding hypertensive disorders, epilepsy, and medication exposure. Some features of neurocutaneous disorders may be worsened or accelerated by pregnancy. Neurocutaneous disorders can often be diagnosed prenatally. Therefore, directed assessment should be offered to affected individuals with a personal or family history of a neurocutaneous disorder.

Conclusion and Relevance

Patients affected by neurocutaneous disorders who are pregnant or planning for future pregnancy should be carefully followed by a multidisciplinary team, which could include maternal-fetal medicine, neurology, and anesthesia, as well as other relevant subspecialists. Additional research is required regarding optimal counseling and management of these patients.

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

Von Hippel‐Lindau disease is a rare inherited cancer‐predisposition syndrome. The authors report the updated recommendations for the multiorgan surveillance protocols.

Von Hippel-Lindau Disease (VHL): Characteristic Lesions with Classic Imaging Findings

Von Hippel-Lindau disease (VHL) is a multisystem cancer syndrome caused by the inactivation of the VHL tumor suppressor gene and involves various organ systems including the central nervous system (CNS), endocrine system, and the kidneys. Tumors seen in patients with VHL disease can be benign or malignant and are usually multifocal, bilateral, and hypervascular in nature. As most lesions associated with VHL are asymptomatic initially, early diagnosis and the institution of an evidence-based surveillance protocol are of paramount importance. Screening, surveillance, and genetic counseling are key aspects in the management of patients diagnosed with VHL disease and often require a multidisciplinary approach and referral to specialized centers. This article will discuss the characteristic lesions seen with VHL disease, their diagnosis, screening protocols and management strategies, as well as an illustrative case to demonstrate the natural progression of the disease with classic imaging findings.

Von Hippel-Lindau Disease (VHL): Characteristic Lesions with Classic Imaging Findings

Von Hippel-Lindau disease (VHL) is a multisystem cancer syndrome caused by the inactivation of the VHL tumor suppressor gene and involves various organ systems including the central nervous system (CNS), endocrine system, and the kidneys. Tumors seen in patients with VHL disease can be benign or malignant and are usually multifocal, bilateral, and hypervascular in nature. As most lesions associated with VHL are asymptomatic initially, early diagnosis and the institution of an evidence-based surveillance protocol are of paramount importance. Screening, surveillance, and genetic counseling are key aspects in the management of patients diagnosed with VHL disease and often require a multidisciplinary approach and referral to specialized centers. This article will discuss the characteristic lesions seen with VHL disease, their diagnosis, screening protocols and management strategies, as well as an illustrative case to demonstrate the natural progression of the disease with classic imaging findings.