Biological and clinical impact of hemangioblastoma-associated peritumoral cysts in von Hippel-Lindau disease

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.

Radiosurgically Treated Recurrent Cerebellar Hemangioblastoma: A Case Report and Literature Review

BACKGROUND

Cystic, sporadic hemangioblastomas (HBLs) represent a unique, therapeutically challenging subset of central nervous system tumors, mainly due to their unpredictable growth patterns and potential for symptomatic progression. This study aims to explore the complexities surrounding the diagnosis, treatment, and long-term management of these lesions.

METHODS

A comprehensive literature review was performed, and a detailed case study of a 56-year-old patient with a cystic, sporadic cerebellar HBL was produced.

RESULTS

The case highlights the multiphasic growth pattern typical of cystic, sporadic HBLs, characterized by periods of dormancy and subsequent rapid expansion. An initial surgical intervention offered temporary control. Tumor recurrence, mainly through cystic enlargement, was treated by SRS. A subsequent recurrence, again caused by cystic growth, eventually led to the patient's death. The intricacies of treatment modalities, focusing on the transition from surgical resection to stereotactic radiosurgery (SRS) upon recurrence, are discussed. Parameters indicating impending tumor growth, coupled with symptomatic advances, are also explored.

CONCLUSIONS

The management of cystic, sporadic cerebellar HBLs requires a strategic approach that can be informed by radiological characteristics and tumoral behavior. This study underscores the importance of a proactive, individualized management plan and suggests guidelines that could inform clinical decision making.

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.

Proteomic Analysis on Sequential Samples of Cystic Fluid Obtained from Human Brain Tumors

Cystic formation in human primary brain tumors is a relatively rare event whose incidence varies widely according to the histotype of the tumor. Composition of the cystic fluid has mostly been characterized in samples collected at the time of tumor resection and no indications of the evolution of cystic content are available. We characterized the evolution of the proteome of cystic fluid using a bottom-up proteomic approach on sequential samples obtained from secretory meningioma (SM), cystic schwannoma (CS) and cystic high-grade glioma (CG). We identified 1008 different proteins; 74 of these proteins were found at least once in the cystic fluid of all tumors. The most abundant proteins common to all tumors studied derived from plasma, with the exception of prostaglandin D2 synthase, which is a marker of cerebrospinal fluid origin. Overall, the protein composition of cystic fluid obtained at different times from the same tumor remained stable. After the identification of differentially expressed proteins (DEPs) and the protein-protein interaction network analysis, we identified the presence of tumor-specific pathways that may help to characterize tumor-host interactions. Our results suggest that plasma proteins leaking from local blood-brain barrier disruption are important contributors to cyst fluid formation, but cerebrospinal fluid (CSF) and the tumor itself also contribute to the cystic fluid proteome and, in some cases, as with immunoglobulin G, shows tumor-specific variations that cannot be simply explained by differences in vessel permeability or blood contamination.

α-SMA positive vascular mural cells suppress cyst formation in hemangioblastoma

Approximately 60% of hemangioblastomas (HBs) have peritumoral cysts adjacent to the tumor, which can cause neurological deficits due to the mass effect, and the management of cyst formation is a clinical challenge. Vascular mural cells surrounding endothelial cells consist of vascular smooth muscle cells (vSMCs) and pericytes, which are essential elements that support blood vessels and regulate permeability. This study investigated the involvement of mural cells in cyst formation. We analyzed the expression of α-smooth muscle actin (α-SMA), platelet-derived growth factor receptor-beta (PDGFRB), and CD31 in 39 consecutive human cerebellar HBs, 20 of cystic and 19 of solid type. Solid type HBs showed stronger diffuse expression of α-SMA in precapillary arterioles and capillaries within the tumor than cystic type HBs (p = 0.001), whereas there was no difference in PDGFRB and CD31 expression. Detailed observation with immunofluorescence demonstrated that α-SMA was expressed in vascular mural cells surrounding capillaries in the solid rather than in the cystic type. Multivariate analysis including various clinical and pathological factors showed that lower α-SMA expression was significantly correlated with cyst formation (p < 0.001). Our data suggested that vascular mural cells from precapillary arterioles to capillaries expressing α-SMA may be pericytes and play a crucial role in HB cystogenesis.

Deep learning based on preoperative magnetic resonance (MR) images improves the predictive power of survival models in primary spinal cord astrocytomas

BACKGROUND

Prognostic models for spinal cord astrocytoma patients are lacking due to the low incidence of the disease. Here, we aim to develop a fully automated deep learning (DL) pipeline for stratified overall survival (OS) prediction based on preoperative MR images.

METHODS

A total of 587 patients diagnosed with intramedullary tumors were retrospectively enrolled in our hospital to develop an automated pipeline for tumor segmentation and OS prediction. The automated pipeline included a T2WI-based tumor segmentation model and 3 cascaded binary OS prediction models (1-year, 3-year, and 5-year models). For the tumor segmentation model, 439 cases of intramedullary tumors were used to model training and testing using a transfer learning strategy. A total of 138 patients diagnosed with astrocytomas were included to train and test the OS prediction models via 10 × 10-fold cross-validation using CNNs.

RESULTS

The dice of the tumor segmentation model with the test set was 0.852. The results indicated that the best input of OS prediction models was a combination of T2W and T1C images and the tumor mask. The 1-year, 3-year, and 5-year automated OS prediction models achieved accuracies of 86.0%, 84.0%, and 88.0% and AUCs of 0.881 (95% CI 0.839-0.918), 0.862 (95% CI 0.827-0.901), and 0.905 (95% CI 0.867-0.942), respectively. The automated DL pipeline achieved 4-class OS prediction (<1 year, 1-3 years, 3-5 years, and >5 years) with 75.3% accuracy.

CONCLUSIONS

We proposed an automated DL pipeline for segmenting spinal cord astrocytomas and stratifying OS based on preoperative MR images.

Pediatric Spinal Hemangioblastomas: Clinical Features and Surgical Outcomes of 39 Cases

Objective: Spinal hemangioblastomas (HBs) are a rare pathology, especially in the pediatric population. The natural history and long-term outcomes of pediatric patients with spinal HBs remain unclear due to their scarcity.Methods: A retrospective review of the clinical data and treatment outcomes of children with spinal HBs in our institution from 2012 to 2021 was conducted.Results: Thirty-nine pediatric patients were included, with an average age of 15.9 ± 2.9 years (range, 8–18 years), and 51.3% were female. Children were more likely to have von Hippel-Lindau (VHL) disease (p < 0.001), a family history of VHL (p < 0.001), multiple symptoms (p = 0.006), a shorter duration of symptoms (p < 0.001), and a larger lesion size (p = 0.004) and volume (p = 0.008) than their adult counterparts. The VHL-associated group of patients was more likely to present with multiple symptoms (p = 0.026), have a family history of VHL (p < 0.001), have multiple HBs (p < 0.001) and have synchronous intracranial lesions (p < 0.001) than the sporadic group. After surgery, 15 patients (38.5%) showed improved clinical outcomes, 17 patients (43.6%) remained unchanged, 4 patients (10.2%) worsened, and 3 patients (7.7%) died of tumor progression. During follow-up, there was a high rate of recurrence and repeated surgery, especially for children in the VHL-associated group.Conclusion: Pediatric patients with spinal HBs appear to have a higher relapse risk than their adult counterparts. Therefore, life-long follow-up of these patients is necessary, especially for VHL-associated cases. Surgery can benefit children with HBs and should be considered early to avoid irreversible neurological deterioration.

Clinical characteristics, surgical management, and prognostic factors for supratentorial hemangioblastoma: A retrospective study

Background

Supratentorial hemangioblastoma is an extremely rare neoplasm. The aim of this study is to delineate the clinical features among cystic and solid supratentorial hemangioblastoma patients and evaluate the risk factors for progression-free survival (PFS).

Methods

We conducted a literature search in PubMed for histopathologically identified supratentorial hemangioblastoma between 1947 and 2021 and extracted and collected the clinical features of patients treated at our own institute. The rate of PFS was determined using Kaplan-Meier analysis. Differences in categorical factors, such as the location of tumor and diagnosis of von Hippel-Lindau disease, were analyzed using the Pearson χ ² test. A Cox regression analysis was performed to evaluate the association between various variates and survival outcomes.

Results

A total of 237 cases of supratentorial hemangioblastoma were identified from 169 studies. A survival analysis found that patients with cystic tumors had a significantly better prognosis than those with solid tumors (log-rank, p = 0.0122). Cox regression analysis suggested that cystic hemangioblastoma (hazard ratio (HR): 0.186, 95% CI: 0.043-0.803, p < 0.05) and gross total resection (GTR) (HR: 0.126, 95% CI: 0.049-0.323, p < 0.001) were significant predictors of longer survival (PFS) for supratentorial hemangioblastoma. Following an analysis of 13 supratentorial hemangioblastoma cases from our institute, we validated that cystic tumor had improved prognosis than solid tumor (log-rank, p = 0.0096) and GTR was superior to subtotal resection (log-rank, p = 0.0029).

Conclusions

Cystic hemangioblastoma vs. solid hemangioblastoma may be two tumoral statuses with different clinical features, and a specific treatment strategy should be considered.

[Stereotactic irradiation for optic nerve hemangioblastoma associated with Von Hippel-Lindau disease: a case report and literature review]

Hemangioblastoma is a benign tumor of the central nervous system arising sporadically or as a component of Von Hippel-Lindau disease. Von Hippel-Lindau disease is a rare autosomal dominant hereditary syndrome with various phenotypes caused by VHL gene variants. To date, only about 40 cases of optic nerve hemangioblastoma have been described in the literature. Stereotactic irradiation may be effective for supratentorial hemangioblastomas including lesions of optic nerves. The authors describe a rare case of stereotactic irradiation of intraorbital hemangioblastoma of the optic nerve in a patient with Von Hippel-Lindau disease.

Systemic Therapy Development in Von Hippel-Lindau Disease: An Outsized Contribution from an Orphan Disease

Over the last several decades, an improved understanding of von Hippel-Lindau disease and its underlying biology has informed the successful development of numerous anti-cancer agents, particularly for the treatment of advanced renal cell carcinoma. Most recently, this has culminated in the first regulatory approval for a systemic therapy for VHL disease-associated neoplasms. This review will trace the clinical development of systemic therapies for VHL disease and additionally highlight anticipated challenges and opportunities for future VHL systemic therapy.

Presentation, imaging, patterns of care, growth, and outcome in sporadic and von Hippel-Lindau-associated central nervous system hemangioblastomas

OBJECT

Hemangioblastoma is a relatively rare neoplasm occurring mostly in the cerebellum that may arise sporadically or in the context of von Hippel-Lindau (VHL) syndrome. Presentation, imaging, natural history, surgical patterns of care, and outcomes are incompletely defined for this uncommon lesion. We reviewed our large institutional series to help clarify these issues.

METHODS

Retrospective analysis of consecutive, neurosurgically managed CNS hemangioblastomas at Mayo Clinic, 1988-2018.

RESULTS

Two hundred and eighty five hemangioblastomas were treated in 184 unique patients (115 sporadic, 69 VHL). Compared to sporadic patients, VHL patients were younger (36.7 vs 51.7 years; p < 0.0001), were treated while asymptomatic more commonly (47.3 vs 4.2%; p < 0.0001), had smaller lesions (6.6 vs 13.9 mL; p < 0.0001), and harbored lesions with associated cysts less frequently (51.0 vs 75.0%; p = 0.0002). Macrocystic tumor architecture was associated with larger lesion size and greater symptom severity. Solid lesions later formed cysts at a median 130 months. Growth in both total volume and solid component accelerated after cyst formation (10.6 and 6.0 times median rate prior to cyst emergence). VHL patients died at a younger age (47.9 vs 74.5, p = 0.0017) and were more likely to die of direct disease sequelae. Though treatment-free survival time was significantly longer in sporadic cases, a substantial fraction (> 40%) developed tumor recurrence/progression requiring additional treatment.

CONCLUSIONS

Hemangioblastoma presentation varies with etiology and clinical course is more complicated in VHL cases. Nodular lesions often develop cysts over time which is associated with accelerated tumor growth. Sporadic cases have a previously unappreciated but substantial risk of late recurrence/progression requiring treatment.

Evaluation of tumour surveillance protocols and outcomes in von Hippel-Lindau disease in a national health service

Background

Von Hippel-Lindau (VHL) disease is an inherited tumour predisposition syndrome and a paradigm for the importance of early diagnosis and surveillance. However, there is limited information on the “real world” management of VHL disease.

Methods

A national audit of VHL disease in the United Kingdom.

Results

VHL disease was managed mostly via specialist clinics coordinated through regional clinical genetics services (but frequently involving additional specialties). Over the study period, 19 genetic centres saw 842 individuals (393 males, 449 females) with a clinical and/or molecular diagnosis of VHL disease and 74 individuals (35 male, 39 female) with a prior risk of 50% (affected parent). All centres offered retinal, central nervous system and abdominal surveillance to affected individuals and at-risk relatives though surveillance details differed between centres (but complied with international recommendations). Renal lesions detected on the first surveillance scan were, on average, larger than those detected during subsequent scans and the larger the diameter at detection the greater the likelihood of early intervention.

Conclusions

In a state-funded health care system individuals with a rare inherited cancer predisposition syndrome are generally able to access appropriate surveillance and patient management is improved compared to historical data. The “real world” data from this study will inform the future development of VHL management protocols.

Hemangioblastoma diagnosis and surveillance in von Hippel-Lindau disease: a consensus statement

OBJECTIVE

Hemangioblastomas are a frequent underlying cause of neurological morbidity and death in patients with von Hippel-Lindau disease (VHL). Although these benign tumors can cause significant neurological debility when undetected and untreated, unified evidence-based surveillance recommendations for VHL patients have not been established. To develop consensus recommendations, the VHL Alliance established an expert committee, named the International VHL Surveillance Guidelines Consortium, to define surveillance recommendations.

METHODS

The Central Nervous System (CNS) Hemangioblastoma Subcommittee of the Guidelines Consortium was formed as a multidisciplinary team of experts in the diagnosis and management of hemangioblastomas. Recommendations were formulated using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) and National Comprehensive Cancer Network Categories of Evidence and Consensus categorization after a comprehensive literature review.

RESULTS

Published studies (n = 49) that discussed age at onset, MRI frequency, natural history of VHL, and the risks and benefits of surveillance were analyzed. Based on this analysis, the authors recommend that clinical evaluation (yearly) be used as the primary screening tool for hemangioblastomas in VHL. The subcommittee suggests that screening be performed between the ages of 11 and 65 years, or with the onset of symptoms, for synchronicity with other testing regimens in VHL. The subcommittee also recommends that baseline MRI be first performed at the age of 11 years (suggested 2B, level of evidence D) or after identification of neurological symptoms or signs (if earlier) and continue every 2 years (recommended 2A, level of evidence A).

CONCLUSIONS

The CNS Hemangioblastoma Subcommittee of the International VHL Surveillance Guidelines Consortium here proposes guidelines that aim to increase the early detection of VHL-associated hemangioblastomas to reduce their morbidity and mortality.

Multiple VHL-related hemangioblastomas and holocord syrinx: identifying the causative lesion. Illustrative case

BACKGROUND

Brainstem and spinal cord hemangioblastomas are a common manifestation of von Hippel–Lindau (VHL) disease. Cysts and associated syringes are the most common cause of significant morbidity in these patients. Surgical treatment of symptomatic hemangioblastomas are often complicated by the presence of multiple potential lesions, leading to cyst and syrinx formation.

OBSERVATIONS

The authors present a case of a patient with multiple VHL-related hemangioblastomas who presented with syringobulbia and holocord syrinx. Resection of two cyst wall hemangioblastomas and one cervical hemangioblastoma only transiently improved syringobulbia. Eventual resolution of syringobulbia and collapse of the holocord syrinx only occurred following removal of a large lower thoracic hemangioblastoma.

LESSONS

Surgical management of hemangioblastomas and associated cysts in patients with VHL should only target lesions most likely contributing to neurological deficits as excess surgical intervention risks treatment-related morbidity. The authors illustrate how anatomical and pathophysiological considerations as well as patient symptoms are key to identifying target lesions for resection and developing deliberate treatment plans.

Automatic multiclass intramedullary spinal cord tumor segmentation on MRI with deep learning

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Automatic spinal cord tumor segmentation with deep learning.

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Multi-class model for tumor, edema, and cavity.

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Model trained to recognize astrocytoma, ependymoma, and hemangioblastoma.

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Multi-contrast input for more robustness: Gd-T1w and T2w.

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Method and model are available in open-source Spinal Cord Toolbox (SCT).

Spinal cord tumors lead to neurological morbidity and mortality. Being able to obtain morphometric quantification (size, location, growth rate) of the tumor, edema, and cavity can result in improved monitoring and treatment planning. Such quantification requires the segmentation of these structures into three separate classes. However, manual segmentation of three-dimensional structures is time consuming, tedious and prone to intra- and inter-rater variability, motivating the development of automated methods. Here, we tailor a model adapted to the spinal cord tumor segmentation task. Data were obtained from 343 patients using gadolinium-enhanced T1-weighted and T2-weighted MRI scans with cervical, thoracic, and/or lumbar coverage. The dataset includes the three most common intramedullary spinal cord tumor types: astrocytomas, ependymomas, and hemangioblastomas. The proposed approach is a cascaded architecture with U-Net-based models that segments tumors in a two-stage process: locate and label. The model first finds the spinal cord and generates bounding box coordinates. The images are cropped according to this output, leading to a reduced field of view, which mitigates class imbalance. The tumor is then segmented. The segmentation of the tumor, cavity, and edema (as a single class) reached 76.7 ± 1.5% of Dice score and the segmentation of tumors alone reached 61.8 ± 4.0% Dice score. The true positive detection rate was above 87% for tumor, edema, and cavity. To the best of our knowledge, this is the first fully automatic deep learning model for spinal cord tumor segmentation. The multiclass segmentation pipeline is available in the Spinal Cord Toolbox (https://spinalcordtoolbox.com/). It can be run with custom data on a regular computer within seconds.

Central Nervous System Hemangioblastoma in a Pediatric Patient Associated With Von Hippel-Lindau Disease: A Case Report and Literature Review

Background

Hemangioblastoma is a benign tumor of the central nervous system and may appear as a component of von Hippel-Lindau (VHL) disease. At present, approximately 40 cases of optic nerve HGBs have been reported in the literature. VHL disease is a rare autosomal-dominant inherited cancer syndrome with different phenotypes caused by variants in the VHL gene. Herein, the authors describe a case of a pediatric patient with VHL disease and with optic nerve HGB, a rare phenotypic expression. The purpose of this study was to explore the genotype-phenotype, clinical features, treatment and follow-up of VHL-associated hemangioblastomas in pediatric patients.

Case Description

A 12-year-old boy presented with vision loss, headache and dizziness at our hospital. Magnetic resonance imaging (MRI) revealed a large (19.8 mm*18.5 mm*23.5 mm) irregular mass located in the suprasellar region. The mass was successfully removed after craniotomy and microsurgical treatment. The pathological diagnosis was left optic nerve HGB. Genetic analyses showed p.Pro86Leu (c. 257C>T) heterozygous missense mutations in the VHL gene.

Conclusion

This is the first reported pediatric case of VHL-associated optic nerve HGB. The genotype-phenotype correlation of VHL disease may provide new evidences for predicting tumor penetrance and survival. Gross tumor resection combined with stereotactic radiosurgery might be the most beneficial treatment.

Combined transcriptomic and lipidomic analysis reveals aberrant lipid metabolism in central nervous system hemangioblastomas

Peritumoral cysts are commonly detected in the central nervous system tumors, especially hemangioblastomas (HBs). However, the molecular mechanisms driving their formation and propagation are still unknown. We conducted an integrated lipidomics and transcriptomics analysis on solid and cystic HB samples in order to elucidate the changes in the lipid profile and expression of lipid metabolism-related genes during cyst formation. Transcriptomic analysis revealed differential expression of several genes between the solid and cystic HBs, and those associated with lipid metabolism, such as ADCY4, MGLL, ACOT2, DGKG, SHC1 and LPAR2, were markedly dysregulated in the cystic HBs. The lipidomic analysis further showed a significant reduction in the abundance of triacylglycerol, ceramide, lysophosphatidylcholine and lysophosphatidylethanolamine, and an increase in phosphatidylcholine and phosphatidylethanolamine levels in the cystic HBs. Furthermore, bioinformatics analysis revealed altered lipid biosynthesis, glycerophospholipid metabolism and phospholipase activity in the cystic HBs. Taken together, our findings indicate that cyst formation in HBs is related with aberrant lipid metabolism.

Intermixed arteriovenous malformation and hemangioblastoma: case report and literature review

We report the third presentation of an intermixed arteriovenous malformation and hemangioblastoma. The rare occurrence of the diagnostic histologic features of both a neoplasm and vascular malformation in a single lesion is more common in gliomas, as angioglioma, and is termed an 'intermixed' lesion. We review the literature concerning the developmental biology of each lesion, and potential interplay in the formation of an intermixed vascular neoplasm and vascular malformation. The roles of cellular origin, genetic susceptibility, favourable microenvironment, altered local gene expression and key regulatory pathways are reviewed. Our review supports angiography and genetic profiling in intermixed lesions to inform management strategies. Consideration should be given to multimodality therapeutic interventions as required, including microsurgical resection, stereotactic radiosurgery and further research to exploit emerging molecular targets.

Biological and clinical impact of central nervous system hemangioblastomas in Chinese patients with von Hippel-Lindau disease: implications for treatment

Objective

Central nervous system (CNS) hemangioblastomas (HGBs) are the most frequent cause of mortality in patients with von Hippel-Lindau (VHL) genetic syndrome. However, there is a lack of large studies on the clinical features and optimal management of HGBs in Chinese patients.

Methods

VHL-related HGB cases treated surgically at our hospital from 2012 to 2019 were evaluated. Patients and family members meeting the clinical diagnostic criteria underwent genetic testing. Clinical, genetic and relevant imaging data were analyzed.

Results

Eighty-five VHL patients from 34 pedigrees in 16 Chinese provinces who underwent 121 operations for CNS HGBs were enrolled. Multiple operations were associated with a younger age at first operation (OR = 0.926, 95% CI = 0.871–0.985, P = 0.014, threshold: 27.5, sensitivity: 72.2%, specificity: 71.2%) and a longer postoperative period (OR = 1.096, 95% CI = 1.015–1.184, P = 0.019, threshold: 10.5, sensitivity: 66.7%, specificity: 76.3%). The age at first operation was younger in children than in their parents (23 pairs, P < 0.001). The age at first operation was younger in siblings born later than in those born earlier (10 pairs, P = 0.01). Most untreated tumors (98.2%) remained relatively stable during follow-up (range, 0.5–7; median, 2). However, new tumors continued to emerge (0.14 tumor/year).

Conclusion

VHL-associated CNS HGB is a long-term chronic disease with repeated attacks, likely with genetic anticipation in Chinese pedigrees. When the age at first operation is under 27.5 years, or the postoperative period is longer than 10.5 years, the risk of multiple operations is increased. While most unresected HGBs remain stable after surgery, new tumors may still slowly emerge; hence, scheduled follow-ups are necessary.

VON HIPPEL-LINDAU DISEASE: Update on Pathogenesis and Systemic Aspects

PURPOSE

To provide an update summarizing the biologic pathways governing von Hippel-Lindau (VHL) disease pathogenesis and to provide an overview of systemic manifestations as well as screening recommendations.

METHODS

A PubMed search of the English language literature was reviewed using the following search terms: von Hippel-Lindau, von Hippel-Lindau disease, and VHL. Of 6,696 publications, the most current and pertinent information related to the pathogenesis and systemic aspects of VHL disease were included in this review.

RESULTS

von Hippel-Lindau disease is one of the most frequently occurring multisystem familial cancer syndromes. The disease results from germline mutation in the VHL tumor suppressor gene on the short arm of chromosome 3. Mutation in the VHL gene affects multiple cellular processes including transcriptional regulation, extracellular matrix formation, apoptosis, and, in particular, the cellular adaptive response to hypoxia. As a result, there is widespread development of vascular tumors affecting the retina, brain, and spine, as well as a spectrum of benign and malignant tumors and/or cysts in visceral organs.

CONCLUSION

The ophthalmologist plays a key role in VHL disease diagnosis, as retinal hemangioblastoma is frequently the first disease manifestation. Screening guidelines for individuals with known VHL disease, and those at risk of VHL disease, help to ensure early detection of potentially vision-threatening and life-threatening disease.

Hemangioblastoma and von Hippel-Lindau disease: genetic background, spectrum of disease, and neurosurgical treatment

INTRODUCTION

Hemangioblastomas are rare, histologically benign, highly vascularized tumors of the brain, the spinal cord, and the retina, occurring sporadically or associated with the autosomal dominant inherited von Hippel-Lindau (VHL) disease. Children or adults with VHL disease have one of > 300 known germline mutations of the VHL gene located on chromosome 3. They are prone to develop hemangioblastomas, extremely rarely starting at age 6, rarely at age 12-18, and, typically and almost all, as adults. There is a plethora of VHL-associated tumors and cysts, mainly in the kidney, pancreas, adrenals, reproductive organs, and central nervous system. Due to a lack of causal treatment, alleviation of symptoms and prevention of permanent neurological deficits as well as malignant transformation are the main task. Paucity of data and the nonlinear course of tumor progression make management of pediatric VHL patients with hemangioblastomas challenging.

METHODS

The Freiburg surveillance protocol was developed by combining data from the literature and our experience of examinations of > 300 VHL patients per year at our university VHL center.

RESULTS

Key recommendations are to start screening of patients at risk by funduscopy with dilated pupils for retinal tumors with admission to school and with MRI of the brain and spinal cord at age 14, then continue biannually until age 18, with emergency MRI in case of neurological symptoms. Indication for surgery remains personalized and should be approved by an experienced VHL board, but we regard neurological symptoms, rapid tumor growth, or critically large tumor/cyst sizes as the key indications to remove hemangioblastomas. Since repeated surgery on hemangioblastomas in VHL patients is not rare, modern neurosurgical techniques should encompass microsurgery, neuronavigation, intraoperative neuromonitoring, fluorescein dye-based intraoperative angiography, intraoperative ultrasound, and minimally invasive approaches, preceded in selected cases by endovascular embolization. Highly specialized neurosurgeons are able to achieve a very low risk of permanent morbidity for the removal of hemangioblastomas from the cerebellum and spinal cord. Small retinal tumors of the peripheral retina can be treated by laser coagulation, larger tumors by cryocoagulation or brachytherapy.

CONCLUSION

We consider management at experienced VHL centers mandatory and careful surveillance and monitoring of asymptomatic lesions are required to prevent unnecessary operations and minimize morbidity.

Functional Outcome After Resection of Von Hippel-Lindau Disease-Associated Cauda Equina Hemangioblastomas: An Observational Cohort Study

BACKGROUND

Cauda equina hemangioblastomas in von Hippel-Lindau (VHL) disease can cause significant neurological signs and symptoms. Despite their associated morbidity, the management of these tumors remains incompletely defined.

OBJECTIVE

To determine optimal management, we analyzed the functional outcomes after resection of these tumors.

METHODS

VHL patients who underwent surgical resection of cauda equina hemangioblastomas at the National Institutes of Health and the University of Virginia were included. Clinical and radiological follow-up was performed at 6- to 12-month intervals after surgery.

RESULTS

Fifteen patients underwent 18 operations for 21 cauda equina hemangioblastomas (median follow-up 5.9 years). Patients often presented with multiple symptoms, including pain (67%), numbness (50%), urinary complaints (33%), and weakness (11%). Median preoperative tumor volume was 1.2 cm 3 . Four tumors at 3 operations were not resected due to a motor nerve root origin. Gross total resection was achieved in 14 surgeries (93% of operations when resection was attempted). New mild (non-function limiting) neurological symptoms were noted after 11 operations (61%), which most often (64%) resolved within 2 weeks of surgery. At 6-month follow-up, 15 patients (83%) were stable, 2 (11%) were improved, and 1 (6%) was worse. Histological analysis revealed that all tumors originated from within the involved nerve fascicle.

CONCLUSIONS

VHL-associated cauda equina hemangioblastomas have an intrafascicular origin and require interruption of the rootlet of origin for complete resection. Motor nerve root involvement may preclude complete resection but strategies including bony decompression and/or interruption of vascular supply may provide a therapeutic option. Nevertheless, most VHL patients with symptom-producing lesions improve with resection.

Pazopanib in patients with von Hippel-Lindau disease: a single-arm, single-centre, phase 2 trial

BACKGROUND

No approved systemic therapy exists for von Hippel-Lindau disease, an autosomal dominant disorder with pleiotropic organ manifestations that include clear cell renal cell carcinomas; retinal, cerebellar, and spinal haemangioblastomas; pheochromocytomas; pancreatic serous cystadenomas; and pancreatic neuroendocrine tumours. We aimed to assess the activity and safety of pazopanib in patients with von Hippel-Lindau disease.

METHODS

In this non-randomised, single-centre, open-label, phase 2 trial, adult patients with clinical manifestations of von Hippel-Lindau disease were recruited from the University of Texas MD Anderson Cancer Center (Houston, TX, USA) and were treated with pazopanib (800 mg orally daily) for 24 weeks, with an option to continue treatment if desired by the patient and treating physician. Primary endpoints were the proportion of patients who achieved an objective response and safety in the per-protocol population. The objective response was measured for each patient and each lesion type. Radiographic assessments were done at baseline and every 12 weeks throughout the study. Activity and safety were assessed with continuous monitoring and a Bayesian design. This study is registered with ClinicalTrials.gov, number NCT01436227, and is closed to accrual.

FINDINGS

Between Jan 18, 2012, and Aug 10, 2016, we screened 37 patients with genetically confirmed or clinical features consistent with von Hippel-Lindau disease, of whom 31 eligible patients were treated with pazopanib. The proportion of patients who achieved an objective response was 42% (13 of 31 patients). By lesion sites responses were observed in 31 (52%) of 59 renal cell carcinomas, nine (53%) of 17 pancreatic lesions, and two (4%) of 49 CNS haemangioblastomas. Seven (23%) of 31 patients chose to stay on the treatment after 24 weeks. Four (13%) of 31 patients withdrew from the study because of grade 3 or 4 transaminitis, and three (10%) discontinued study treatment because of treatment intolerance with multiple intercurrent grade 1-2 toxicities. Treatment-related serious adverse events included one case each of appendicitis and gastritis and one patient had a fatal CNS bleed.

INTERPRETATION

Pazopanib was associated with encouraging preliminary activity in von Hippel-Lindau disease, with a side-effect profile consistent with that seen in previous trials. Pazopanib could be considered as a treatment choice for patients with von Hippel-Lindau disease and growing lesions, or to reduce the size of unresectable lesions in these patients. The safety and activity of pazopanib in this setting warrants further investigation.

FUNDING

Novartis Inc and NIH National Cancer Institute core grant.

Von Hippel-Lindau and Hereditary Pheochromocytoma/Paraganglioma Syndromes: Clinical Features, Genetics, and Surveillance Recommendations in Childhood

Von Hippel-Lindau disease (vHL) is a hereditary tumor predisposition syndrome that places affected individuals at risk for multiple tumors, which are predominantly benign and generally occur in the central nervous system or abdomen. Although the majority of tumors occur in adults, children and adolescents with the condition develop a significant proportion of vHL manifestations and are vulnerable to delayed tumor detection and their sequelae. Although multiple tumor screening paradigms are currently being utilized for patients with vHL, surveillance should be reassessed as the available relevant clinical information continues to expand. We propose a new vHL screening paradigm similar to existing approaches, with important modifications for some tumor types, placing an emphasis on risks in childhood. This includes advancement in the timing of surveillance initiation and increased frequency of screening evaluations. Another neuroendocrine-related familial condition is the rapidly expanding hereditary paraganglioma and pheochromocytoma syndrome (HPP). The tumor spectrum for patients with HPP syndrome includes paragangliomas, pheochromocytomas, renal cancer, and gastrointestinal stromal tumors. The majority of patients with HPP syndrome harbor an underlying variant in one of the SHDx genes (SDHA, SDHB, SDHC, SDHD, SDHA, and SDHAF2), although other genes also have been described (MAX and TMEM127). Annual screening for elevated plasma or urine markers along with complete blood count and biennial whole-body MRI accompanied by focal neck MRI is recommended for older children and adults with HPP syndrome to detect tumors early and to decrease morbidity and mortality from HPP-related tumors. Clin Cancer Res; 23(12); e68-e75. ©2017 AACRSee all articles in the online-only CCR Pediatric Oncology Series.

Von Hippel-Lindau disease: a single gene, several hereditary tumors

The Von Hippel-Lindau (VHL) disease is an autosomal dominant disorder characterized by the predisposition for multiple tumors caused by germline mutations in the tumor suppressor gene VHL. This disease is associated with a high morbidity and mortality and presents a variable expression, with different phenotypes from family to family, affecting different organs during the lifetime. The main manifestations of VHL are hemangioblastomas of the central nervous system and retina, renal carcinomas and cysts, bilateral pheochromocytomas, cystic and solid tumors of the pancreas, cystadenomas of the epididymis, and endolymphatic sac tumors. The discovery of any of the syndrome components should raise suspicion of this disease and other stigmas must then be investigated. Due to the complexities associated with management of the various VHL manifestation, the diagnosis and the follow-up of this syndrome is a challenge in the clinical practice and a multidisciplinary approach is needed. The particular relevance to endocrinologists is the detection of pheochromocytomas in 35% and islet cell tumors in 17% of VHL patients, which can be associated with hypertension, hypoglycemia, cardiac arrhythmias, and carcinoid syndrome. The purpose of this review is to define the Von Hippel-Lindau syndrome addressing its clinical aspects and classification, the importance of genetic counseling and to propose a protocol for clinical follow-up.

Stereotactic radiosurgery for central nervous system hemangioblastoma: systematic review and meta-analysis

Hemangioblastomas are rare, benign, vascular tumors of the central nervous system (CNS), often associated with von-hippel lindau (VHL) disease. Current therapeutic options include microsurgical resection or stereotactic radiosurgery (SRS). With no randomized controlled studies and minimal data beyond single-institution reviews, the optimal management approach for patients with CNS hemangioblastomas is unclear. We completed a Pubmed/SCOPUS literature search from January 1990 to January 2017 for eligible studies on SRS for CNS hemangioblastomas. Relevant articles were identified and reviewed in accordance to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. 26 studies met eligibility criteria for qualitative synthesis, representing 596 subjects and 1535 tumors. The Gamma Knife was the most published SRS method for CNS hemangioblastomas. After critical study appraisal for intra-study bias, 14 studies were used for quantitative meta-analysis of 5-year progression free survival (PFS). The pooled 5-year PFS across all eligible studies was 88.4%. No difference was observed between spine versus intracranial studies. Individual patient data (IPD) was extracted from 14 studies, representing 322 tumors. Univariate analysis of IPD revealed that VHL patients were younger, and had smaller tumors compared to those with sporadic disease. Adverse events were associated with increasing marginal dose, independent of tumor volume. VHL status, sex, radiosurgical method, tumor location, and tumor volume were not found to be significantly associated with tumor progression. Multiple studies show excellent tumor control at 5-year follow up, however, the long-term efficacy of SRS for CNS hemangioblastomas still needs to be investigated, and the studies exploring the role of SRS for early treatment of asymptomatic lesions is wanting.

Pediatric central nervous system hemangioblastomas: different from adult forms? A retrospective series of 25 cases

BACKGROUND

Pediatric hemangioblastomas are rare, and the clinical features, timing of surgical intervention, optimal treatment, and clinical outcomes are still unclear.

METHODS

We performed a retrospective study of all patients with CNS hemangioblastomas who were treated at West China Hospital from January 2003 to March 2015. Patients under the age of 16 years were included in the study. The medical records of these patients were reviewed and statistically analyzed.

RESULTS

Twenty-five children (15 females and ten males, [mean age 12.6 ± 4.7 years, range 1-16 years]) presented with hemangioblastomas. Tumors were detected in the cerebellum, brainstem, and spinal cord in 40, 28, and 32% of patients, respectively. Sixteen children (64%) had VHL syndrome. The most frequent symptoms were those related to increased intracranial pressure. The mean duration of symptoms was 1.5 ± 2.1 months. Preoperative hydrocephalus was noted in 11 children (44%). Gross total resection was achieved in all children. Clinical symptoms improved in 19 children (76%), unchanged in four children (16%), and aggravated in two children (8%), respectively. The mean follow-up was 44.5 ± 32.3 months. Five patients (20%) experienced disease progression. Using univariate analysis, both tumor-associated cysts (P = 0.027) and VHL disease (P = 0.032) were significantly related to postoperative outcomes.

CONCLUSIONS

Pediatric hemangioblastomas have many different clinical features compared with adult cases. A high degree of suspicion for VHL disease should be raised in pediatric hemangioblastomas. Despite many challenges involved, surgical outcomes for pediatric hemangioblastomas are favorable. Lifelong follow-up is mandatory to detect the disease progression.

Expression of angiopoietins in central nervous system hemangioblastomas is associated with cyst formation

PURPOSE

This study aimed to determine the expression of angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), and endothelial tyrosine kinase receptor (Tie-2) in central nervous system (CNS) hemangioblastomas (HBs) and explore the correlation with peritumoral cyst formation.

METHOD

A total of 22 paraffin-embedded specimens derived from 11 cyst-associated and 11 solid solitary CNS HBs were collected for streptavidin-peroxidase immunohistochemical staining. The expression levels of Ang-1, Ang-2 and Tie-2 in cystic and solid HBs were estimated and compared according to the integrated optical density (IOD) of staining in the sections. To further confirm the differential expression of Ang-1 and Ang-2 between cystic and solid HBs, an additional 9 frozen specimens from 5 cyst-associated and 4 solid solitary HBs were collected for Western blot analysis. Clinical histories and radiological records of the patients were reviewed retrospectively.

RESULTS

Compared to normal cerebellum tissue, Ang-1, Ang-2 and Tie-2 were prominently overexpressed in both the stromal cells and endothelial cells of CNS HBs. The expression of Ang-2 and the ratio of Ang-2/Ang-1 in the cystic group were significantly higher than those in the solid group. The intensity of Ang-2 expression in the cystic group was negatively correlated with age. There was no correlation between the expression level of the proteins and sex, tumor location, tumor volume or cyst volume.

CONCLUSIONS

Ang/Tie signaling is upregulated in HBs and is likely associated with the process of intense vascularization and cyst formation. Higher Ang-2 levels and a higher Ang-2/Ang-1 ratio may contribute to cyst formation by increasing the vascular permeability. The decrease in Ang-2 expression with advanced age in cystic-associated HBs may be associated with the reduced growth rate of peritumoral cysts among elderly patients. Ang-2 shows great potential as an effective therapeutic target of symptomatic CNS HBs associated with cysts.

Personalized Medicine for Nervous System Manifestations of von Hippel-Lindau Disease

von Hippel–Lindau disease (VHL) is a familial neoplasia syndrome associated with multisystem tumor development. Depending on tumor type and location, current treatments for VHL-associated tumors can include a combination of chemotherapy, radiation therapy, and/or surgery. Central nervous system (CNS) manifestations of VHL include craniospinal hemangioblastomas and endolymphatic sac tumors (ELSTs). While the first-line treatment for both types of VHL-associated CNS tumors is surgery, the indications for treatment are patient specific and different for each tumor type. Although early sign/symptom formation is the primary indication for resection of craniospinal hemangioblastomas, radiographic discovery (asymptomatic and symptomatic) of ELSTs can be an indication for resection of ELSTs in VHL patients. Recently, research has revealed that specific VHL germline mutations may permit targeted medical treatments of not only CNS manifestations of VHL-associated tumors but also visceral tumors. Specifically, missense mutations can result in the translation of functional VHL protein (pVHL) that is rapidly degraded resulting in functional loss of the pVHL, and inhibitors of pVHL degradation may slow protein degradation and restore pVHL function. Emerging research will investigate the safety and practicality of using potential targeted therapies.