von Hippel-Lindau disease: Updated guideline for diagnosis and surveillance

Very early-onset symptomatic CNS haemangioblastoma in Von Hippel-Lindau disease

Von Hippel-Lindau disease is a genetic disorder characterised by the development of a variety of tumours and cysts, with central nervous system (CNS) haemangioblastoma being the most common manifestation. Early diagnosis through genetic counselling and surveillance is crucial for detecting asymptomatic stages of the disease to minimise morbidity and mortality associated with tumour complications and treatment interventions. In this report, we describe two cases of very early-onset symptomatic CNS haemangioblastoma and discuss the potential improvement in surveillance protocols by including both clinical and genetic factors.

Fibroblast growth factor receptor expression in hemangioblastomas: A novel therapeutic target

Hemangioblastoma is a highly vascularized, benign tumor in the central nervous system, frequently associated with von Hippel-Lindau (VHL) disease. Hemangioblastoma may cause tumor-associated hemorrhage or exert pressure on nearby structures, leading to life-threatening complications. Although surgical resection is the primary treatment, complete removal is not always feasible. Accordingly, there is a need to explore targeted or anti-angiogenic therapies. The fibroblast growth factor receptor (FGFR) family has roles in tumorigenesis and angiogenesis, making it a potential target in personalized therapy. The distribution and significance of FGFRs in hemangioblastoma have yet to be investigated. We examined 139 formalin-fixed, paraffin-embedded hemangioblastoma samples from 111 patients, including sporadic cases and those associated with VHL disease. Immunohistochemistry revealed positive staining for FGFR2 (95%) and FGFR4 (61%), while FGFR1 (0%) and FGFR3 (12%) were mainly negative. FGFR2 expression was significantly increased in VHL-mutated tumors (75%, p = 0.034) and in male patients (68%, p = 0.020). Tumors located in the cerebrum (n = 6, 5%) had a higher likelihood of positive FGFR4 staining (100%, p = 0.009). Additionally, a larger tumor diameter was associated with a higher likelihood of FGFR4 expression (median 12.0 mm vs 17.5 mm, p = 0.018), suggesting its contribution in tumor growth. Our study revealed the expression of FGFR2 and FGFR4 in a significant number of hemangioblastomas. This finding demonstrates the potential of FGFRs as promising therapeutic targets for patients with hemangioblastoma.

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.

Genetics and current research models of Mendelian tumor predisposition syndromes with ocular involvement

In this review, we aim to provide a survey of hereditable tumor predisposition syndromes with a Mendelian inheritance pattern and ocular involvement. We focus our discussion on von Hippel-Lindau disease, neurofibromatosis type 1, NF2-related schwannomatosis, tuberous sclerosis complex, retinoblastoma, and the BAP1 tumor predisposition syndrome. For each of the six diseases, we discuss the clinical presentation and the molecular pathophysiology. We emphasize the genetics, current research models, and therapeutic developments. After reading each disease section, readers should possess an understanding of the clinical presentation, genetic causes and inheritance patterns, and current state of research in disease modeling and treatment.

Pediatric and adolescent von Hippel-Lindau disease: tumor profiles, genotype-phenotype correlation and comparison with adults

PURPOSE

Data on pediatric/adolescent von Hippel-Lindau (VHL) disease is sparse, and surveillance/management recommendations rely on expert opinions/extrapolations from adults. We aimed to characterize the childhood/adolescent VHL disease phenotype, compare it with adults, and identify genotype-phenotype correlations.

METHODS

Retrospective review of children/adolescents (≤ 19 years) and adults with VHL disease from a single endocrine center (2000-2024). Only neoplasms diagnosed until age 19 years were included in the childhood/adolescent group and compared with the last follow-up of adults.

RESULTS

Twenty-six children/adolescents (median age:15.5 years) were identified. By age 19 years, 81% had pheochromocytoma/paraganglioma (PPGL, of which 10% head-neck), 42% central nervous system hemangioblastoma (CNS-HB), 31% each retinal hemangioblastoma (RHB) and pancreatic neuroendocrine tumor (PNET), and none endolymphatic sac tumor/renal cell carcinoma. At diagnosis, all PPGLs were symptomatic (median size 4.5 cm). CNS-HBs showed female preponderance, with high disease burden (60% symptomatic, 50% synchronous) and surgical requirement by 19 years of age. 2/8 pediatric patients needed surgery for symptomatic PNET before recommended surveillance initiation age (15 years). Two children/adolescents developed polycythemia during follow-up. Compared to adults (n = 39), pediatric/adolescent PPGL patients had significantly higher plasma free-normetanephrine/bilateral/extra-adrenal disease and 8.3-fold higher operative-site recurrence. Neoplasm frequency and other characteristics by 19 years resembled adults. Childhood/adolescent PPGLs occurred predominantly (16/17), and PNETs exclusively with missense variants. Codon 167 missense variants were associated with synchronous bilateral pheochromocytomas.

CONCLUSION

In the largest Asian study describing children/adolescents with VHL disease, we report severe pediatric/adolescent phenotype comparable to adults, need for childhood/adolescent HNPGL, and earlier PNET surveillance, particularly with missense variants.

Factors that predict progression of von Hippel-Lindau disease-related malignancy: a longitudinal cohort study

BACKGROUND

Von Hippel-Lindau (vHL) disease encompasses various genetic subtypes with poorly defined progression patterns. This retrospective study of a longitudinal cohort aimed to characterize follow-up duration, treatment rates, and progression patterns according to genomic subtype, and to identify risk factors for progression.

METHODS

Between June 2003 and June 2020, the study enrolled 94 patients (mean age, 37.1 years; 49 females; 84 with missense mutations and 10 with truncating (i.e., insertion/deletion) mutations in the VHL tumor suppressor gene). MRI and CT imaging data were analyzed to compare tumor incidence between the two mutation groups. Cox regression analysis was used to assess predictors of hemangioblastoma (Hb) and renal cell carcinoma (RCC) progression based on genetic subtype, tumor volume, and clinical characteristics.

RESULTS

Patients with missense mutations were more often treated for RCC (p = 0.013) and adrenal pheochromocytoma (p < 0.001) than those with truncating mutations; however, genetic subtype was not a significant predictor of time-to-progression of Hb or RCC. Larger tumor volume at baseline was an independent predictor of Hb progression (HR, 1.029; 95% CI, 1.013-1.046; p < 0.001) and RCC (HR, 1.011; 95% CI, 1.005-1.017; p < 0.001). Male sex was also an independent predictor of RCC progression (HR, 3.368; 95% CI, 1.351-8.396; p = 0.009).

CONCLUSIONS

Genetic subtype was not associated with progression of vHL disease, but missense mutations were associated with higher treatment rates for RCC and adrenal pheochromocytoma. The finding that progression of Hb and RCC is linked to larger baseline tumor volume and male sex may facilitate clinical management.

Mosaic Form of von Hippel-Lindau Syndrome: Case Report and Literature Review

von Hippel-Lindau syndrome (VHLS) is a hereditary cancer syndrome with CNS hemangioblastomas, clear cell renal carcinoma, pheochromocytoma, retinal angiomas, and a number of other manifestations. VHLS is caused by a mutation in the VHL gene and is inherited in an autosomal dominant manner. However, some cases of VHLS develop de novo, and among them, there are rare patients with a mosaic form of the disease. Genetic testing in mosaic patients is prone to false-negative results due to the low copy number of a mutant allele in DNA isolated from the blood. We describe a case of molecular genetic diagnostics of VHLS in a 39-year-old patient using various methods, including mutation analysis in asynchronous primary tumors and repeated DNA analysis from blood using NGS with high coverage for the mutant position. As a result, the patient was diagnosed with a mosaic form of VHLS caused by the variant c.481C>T (p.Arg161Ter), the proportion of which in the blood DNA was 2%. We also summarized the literature data on the mosaic form of VHLS: the severity of clinical manifestations, the features of differential diagnostics of VHLS with a negative result of routine molecular genetic VHL testing, and specific options of active surveillance and treatment for mutation carriers.

Pancreatic Neuroendocrine Tumors in French VHL Mutation Carriers

CONTEXT

Von Hippel-Lindau disease (VHL) is a rare, autosomal-dominant hereditary cancer-predisposition syndrome caused by germline pathogenic variants (PVs) in the VHL gene. It is associated with a high penetrance of benign and malignant vascular tumors in multiple organs, including pancreatic neuroendocrine tumors (PanNETs), whose long-term natural history is ill-known.

OBJECTIVE

The aim of this study was to identify prognostic factors associated with VHL-related PanNETs, notably the role of genotype-phenotype correlations.

METHODS

Patients with both documented germline PV in the VHL gene and PanNETs included in the French PREDIR database between 1995 and 2022 were included. The primary end point was the proportion of patients with PanNET-related metastases, and the secondary end point was overall survival (OS). Genotype/phenotype correlations were studied.

RESULTS

We included 121 patients with 259 PanNETs. Median age at diagnosis was 38 years. Median follow-up was 89.5 months. PanNET surgical resection was performed in 51 patients. Overall, 29 patients (24%) had metastases (5 synchronous, 10 metachronous), with a higher risk in case of larger PanNET size (P = .0089; best threshold 28 mm) and grade 2 PanNET (P = .048), and a pejorative prognostic impact (P = .043). Patients with PV in VHL exon 1 had larger PanNETs (P = .018), more often metastatic disease (48% vs 11.5%; P < .001) and a trend toward shorter OS (P = .16).

CONCLUSION

The risk of metastases associated with VHL-related PanNETs remains low (24%) but increases with tumor size greater than 28 mm, higher grade, and in case of PV, located in VHL exon 1. These data might help improve the management of these patients, who should be referred to an expert center.

Pheochromocytoma in von Hippel-Lindau Disease: Clinical Features and Comparison With Sporadic Pheochromocytoma

OBJECTIVES

Pheochromocytomas and paragangliomas (PPGLs) are manifestations of von Hippel-Lindau (VHL) disease. This study aims to describe the clinical features of PPGLs in VHL patients and the distinctions between VHL disease-related PPGLs and sporadic PPGLs.

DESIGN, PATIENTS AND MEASUREMENTS

The study included all patients with VHL disease and PPGLs treated in a single centre from 2007 to 2023. A total of 145 patients were included in the sporadic PPGLs group. Their clinical data were retrospectively reviewed. Genetic testing for VHL mutation was conducted using Sanger sequencing. Statistical analysis was performed using SPSS 22.

RESULTS

Fifty-nine (65.6%) of the 90 VHL disease patients had PPGLs (male: female, 38:21; age at diagnosis, 25.0 ± 13.3 years). 42 (71.2%) patients had lesions only in the adrenal gland, and 16 (27.1%) patients had lesions both in and out of the adrenal gland. 45 (76.3%) patients had multiple lesions. Eighteen (45.0%) patients developed recurrence after surgery. Fifty-eight patients with PPGLs underwent genetic testing and had pathogenic or likely pathogenic mutations in the VHL gene. Fifty-three (91.4%) patients had missense mutations, 34 of which were located in the Elongin-C binding domain. The hotspot mutation sites were codon 161 and codon 167. Five novel mutations were identified. The clinical characteristics showed no significant differences between groups with different mutation sites. Compared to sporadic PPGLs, VHL disease-related PPGLs were more frequently located in the adrenal gland (71.2% vs. 49.0%, p < 0.001), had a higher prevalence of multiple lesions (76.3% vs. 11.0%, p < 0.001), and secreted noradrenaline (80.4% vs. 43.2%, p < 0.001). They were also more likely to relapse after surgery (45.0% vs. 15.3%, p < 0.001).

CONCLUSION

VHL disease-related PPGLs were often multifocal and noradrenergic, and more likely to relapse compared with sporadic PPGLs. No relationships were identified between the mutation sites and the clinical characteristics of PPGLs.

Management of Pregnancy in a Case of Endolymphatic Sac Tumour as a Part of Von Hippel-Lindau Syndrome Complex: A Case Report and Review of Literature

Endolymphatic sac tumor (ELST) is a rare (1/30000) neoplasm with less than 200 cases reported. It is seen in 24-30% of patients with Von Hippel-Lindau (VHL) syndrome. We present a case of a woman diagnosed to have left cerebello pontine angle endolymphatic sac tumour with low grade adenocarcinoma, underwent left radical mastoidectomy and tumour decompression; developed left cerebellar vermian haemangioma and a left occipito temporal haemangioblastoma who successfully conceived and had an uneventful pregnancy and Caesarean delivery with good maternal and neonatal outcome, due to its rarity. High index of suspicion for an early diagnosis and a planned delivery in a tertiary care centre with a multidisciplinary approach are crucial for successful outcomes.

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.

Unique properties of clinical manifestation and magnetic resonance imaging for differential diagnosis of optic nerve hemangioblastoma

BACKGROUND

To investigate the unique properties of clinical manifestation and radiological imaging for differential diagnosis of optic nerve hemangioblastoma (ONH) from adult optic nerve glioma (ONG) prior to surgical resection.

METHODS

ONH and adult ONG patients were recruited from 2012 to 2022.

RESULTS

A total of seven ONH patients (8 eyes) and 23 adult ONG patients (24 eyes) were assessed. The median onset age of ONH patients was older than that of adult ONG patients (p = 0.007). There were 42.9% (3/7) of ONH patients closely associated with the diagnosis of Von Hippel-Lindau (VHL) syndrome. Notably in Magnetic Resonance Imaging (MRI), the retrobulbar hemangioblastomas in all ONH patients were primarily intraorbital (100%, 8/8), canalicular (87.5%, 7/8), and anterior intracranial (12.5%, 1/8), especially concentrated in the orbital apex, with little posterior optic pathway involvement. Nearly all affected parts of optic nerve in the ONH group (75.0%, 6/8) presented with circumscribed cystic-solid components, characterized by cystic lesions (peritumoral oedema) anteriorly and solid tumours posteriorly, with significant heterogeneous enhancement. Adult ONG lesions prior to extend from the anterior portion to the whole length of the optic nerve, with relatively innocent enlargement in the postcontrast study.

CONCLUSION

Optic nerve tumours in those with older ages at diagnosis (>30 years) or those diagnosed with VHL syndrome are more likely to be indicative of ONH. In the absence of associated VHL syndrome, a distinguishing MRI feature is the concentration of tumours in the orbital apex, characterized by circumscribed cystic-solid components and heterogeneous enhancement of the solid portion.

Arterial Spin-Labeling Perfusion Lightbulb Sign: An Imaging Biomarker of Pediatric Posterior Fossa Hemangioblastoma

BACKGROUND AND PURPOSE

Hemangioblastoma is a rare vascular tumor that occurs within the central nervous system in children. Differentiating hemangioblastoma from other posterior fossa tumors can be challenging on imaging, and preoperative diagnosis can change the neurosurgical approach. We hypothesize that a "lightbulb sign" on the arterial spin-labeling (ASL) sequence (diffuse homogeneous intense hyperperfusion within the solid component of the tumor) will provide additional imaging finding to differentiate hemangioblastoma from other posterior fossa tumors.

MATERIALS AND METHODS

In this retrospective comparative observational study, we only included pathology-proved cases of hemangioblastoma, while the control group consisted of other randomly selected pathology-proved posterior fossa tumors from January 2022 to January 2024. Two blinded neuroradiologists analyzed all applicable MRI sequences, including ASL sequence if available. ASL was analyzed for the lightbulb sign. Disagreements between the radiologists were resolved by a third pediatric neuroradiologist. χ2 and Fisher exact test were used to analyze the data.

RESULTS

Ninety-five patients were enrolled in the study; 57 (60%) were boys. The median age at diagnosis was 8 years old (interquartile range: 3-14). Of the enrolled patients, 8 had hemangioblastoma, and 87 had other posterior fossa tumors, including medulloblastoma (n = 31), pilocytic astrocytoma (n = 23), posterior fossa ependymoma type A (n = 16), and other tumors (n = 17). The comparison of hemangioblastoma versus nonhemangioblastoma showed that peripheral edema (P = .02) and T2-flow void (P = .02) favor hemangioblastoma, whereas reduced diffusion (low ADC) (P = .002) and ventricular system extension (P = .001) favor nonhemangioblastoma tumors. Forty-two cases also had ASL perfusion sequences. While high perfusion favors hemangioblastoma (P = .03), the lightbulb sign shows a complete distinction because all the ASL series of hemangioblastoma cases (n = 4) showed the lightbulb sign, whereas none of the nonhemangioblastoma cases (n = 38) showed the sign (P < .001).

CONCLUSIONS

Lightbulb-like intense and homogeneous hyperperfusion patterns on ASL are helpful in diagnosing posterior fossa hemangioblastoma in children.

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.

The disparity in pediatric spinal cord tumor clinical trials: A scoping review of registered clinical trials from 1989 to 2023

Background

Spinal cord tumors (SCTs) comprise 10% of all central nervous system (CNS) tumors. Pediatric SCTs are often excluded and underrepresented in clinical trials though exclusion rates haven't been reported.

Methods

We reviewed all interventional clinical trials recruiting patients <21 years with SCTs on ClinicalTrials.gov between 1989 and 2023.

Results

Five hundred and two CNS tumor trials were identified, of which 255 included SCTs and/or spincal metastases. Among these, 96.5% were open to all CNS tumors (brain or spine); however, only 3.5% were exclusive to spine tumors. One trial was specific to pediatric spine tumors (inclusive of bone, soft tissue, and neural tumors); no trial was specific to primary pediatric SCTs. Most trials were located in North America, with multisite investigations being more common than single-institution designs. Trials frequently evaluated interventions/treatments (89%), supportive care/quality of life measures (7.1%), or diagnostic protocols (3.1%). Among included treatment paradigms, systemic therapies using cytotoxic chemotherapies, targeted therapies, and/or immunotherapies were more common among brain/spine trials, while radiotherapy, surgical adjuncts, and/or local drug delivery more frequently occurred in spinal tumor trials.

Conclusions

Though SCTs comprise 10% of pediatric CNS tumors, they remain underrepresented in clinical trials. This lack of trials specific to advancing pediatric SCTs management highlights an area of clinical and research need.

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.

Phenotypic and Genotypic Features of a Chinese Cohort with Retinal Hemangioblastoma

Purpose: To delineate the genotype and phenotype of RH in a Chinese cohort. Methods: A group of 51 Chinese probands with RH across 76 eyes was assembled and underwent complete retinal imaging examinations. Sanger sequencing and universal primer quantitative fluorescent multiplex-polymerase chain reaction (UPQFM-PCR) were employed for mutation detection in the coding region of the Von Hippel-Lindal (VHL) gene. For frequency calculation, our series was combined with three large cohorts of East Asian descent through a literature review. Results: The Von Hippel-Lindal (VHL) syndrome was excluded in fifteen patients (median age: 32.00 years) with unilateral solitary RH. Thirty-six patients of younger ages (median: 22.00 years, p = 0.008, Mann-Whitney test) conformed to the diagnostic criteria of the VHL syndrome, and thirty-four patients were genetically confirmed. There were four novel variants identified in the VHL gene. Codons 167, 161 and 86 exhibited a mutation occurrence of more than 5% after pooling with literature data, and the large genomic deletion demonstrated a frequency of 17.65%. The RHs were classified as "extrapapillary", "juxtapapillary" and "mixed" types in 53, 7 and 5 eyes, respectively. Almost all extrapapillary RH lesions were found in the peripheral retina. Hemangioblastomas in the central nervous system (CNS) were observed in 25 out of 31 kindreds (80.65%) with full systemic evaluation data. Conclusions: VHL-associated RH might exhibit earlier onset than non-VHL RH. Large genomic deletions were observed at a notably high frequency in the Chinese series with VHL-associated RH, which might be associated with East Asian ethnicity background. RH could potentially serve as an early indicator of CNS hemangioblastoma.

When rare diseases crisscross within the same patient: von Hippel-Lindau and type 1 gastric neuroendocrine tumor

Von-Hippel-Lindau (VHL) is a genetic multisystem disorder characterized by visceral cysts and benign and malignant tumors in various organs. Herein, we present the case of a 23-year-old woman with VHL presenting with multiple gastric neuroendocrine neoplasms (gNENs) type 1 in the context of chronic autoimmune gastritis (CAG). Although gNENs are not acknowledged as a typical entity in VHL patients, in the present case, gNENs were composed of neoplastic cells with clear cytoplasm usually seen in tumors related to VHL disease. We additionally performed a literature review on the presence of neuroendocrine clear cell tumors and report on further cases of clear cell NENs. The present case illustrates that clear-cell transformation in gNENs may be due to the dual genetic background of the patient; the real oncogenic stimulus may be more closely related to CAG than to VHL disease accompanied by an interplay between neoplastic and autoimmune processes. Therefore, close monitoring of patients with clear cell NENs appears to be important before excluding VHL disease, even in the context of phenotypically unrelated diseases.

Centralization of care for rare genetic syndromes associated with cancer: improving outcomes and advancing research on VHL disease

Von Hippel-Lindau (VHL) disease is a rare genetic syndrome caused by a germline pathogenic variant in one VHL allele. Any somatic event disrupting the other allele induces VHL protein (pVHL) loss of function, ultimately leading to patients developing multiple tumours in multiple organs at multiple timepoints, and reducing life expectancy. Treatment of this complex, rare disease is often fragmented, as patients visit specialist clinicians in isolation at different medical centres. Consequently, patients can receive sub-optimal treatment that results in decreased quality of life and a poor experience of health care systems. In 2021, we established a comprehensive clinical centre at San Raffaele Hospital, Milan, devoted to VHL disease. The centre provides a structured programme for the diagnosis, surveillance and treatment of patients alongside research into VHL disease and involves a multidisciplinary team of dedicated physicians. This programme demonstrates the benefits of care centralization, including concentration of knowledge and services, synergy and multidisciplinary management, improved networking and patient resources, reducing health care costs, and fostering research and innovation. VHL disease provides an ideal model to assess the advantages of centralizing care for rare disease and represents an unparalleled opportunity to broaden our understanding of cancer biology in general.

Phaeochromocytoma and paraganglioma

Phaeochromocytomas and paragangliomas are rare catecholamine-producing neuroendocrine tumours which can potentially cause catastrophic crises with high morbidity and mortality. This best practice article considers the causes and presentation of such tumours, screening and diagnostic tests, management of these patients and consideration of family members at risk.

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.

Unusual Presentation of Von Hippel-Lindau Syndrome With Gastric Variceal Bleeding

Gastric varices are most commonly a complication of portal hypertension or splenic vein thrombosis (SVT). The presence of gastric varices due to portal hypertension is significantly less than the prevalence of esophageal varices. SVT is a known complication of pancreatitis due to inflammation or compression of the splenic vein coursing along the posterior surface of the pancreas. Occlusion of the splenic vein leads to left-sided portal hypertension. Left-sided portal hypertension results in the development of collateral vessels that bypass the splenic vein by connecting with the short gastric veins. The associated increased pressure within the gastric vessels results in gastric varices. Gastric varices due to SVT may occur in the absence of or be disproportionate to esophageal varices. We report an interesting case of gastrointestinal bleeding from gastric varices related to cirrhosis secondary to metabolic dysfunction-associated steatohepatitis and SVT secondary to chronic pancreatitis due to pancreatic neuroendocrine tumor (NET) in a patient diagnosed with von Hippel-Lindau (VHL) syndrome.

Optimal surgical management of unifocal vs. multifocal NF-PNETs: a respective cohort study

BACKGROUND

Pancreatic neuroendocrine tumors (PNETs) represent 1-2% of pancreatic tumors, with recent guidelines recommending active surveillance for non-functioning PNETs (NF-PNETs) smaller than 2 cm. However, the management of multiple NF-PNETs, as well as the influence of tumor number on prognosis, remains under-researched.

METHODS

This retrospective study analyzed NF-PNET patients who underwent pancreatic resection at Severance Hospital between February 1993 and August 2023, comparing the characteristics of patients diagnosed with multifocal tumors and those with unifocal tumors. A subgroup analysis of overall survival (OS) and recurrence-free survival (RFS) was performed based on multifocality employing the Kaplan-Meier method and the log-rank test.

RESULTS

Of 187 patients, 169 (90.4%) had unifocal and 18 (9.6%) had multifocal tumors. Multifocal tumors were more likely to be diffusely spread, necessitating more total pancreatectomies (diffuse tumor location: 4.7% in unifocal vs. 38.9% in multifocal cases, p < 0.001; total pancreatectomy: 4.1% in unifocal vs. 33.3% in multifocal cases, p < 0.001). In patients with NF-PNET who underwent the same extent of pancreatic resection, no significant difference in the incidence of complication was observed regardless of multifocality. Moreover, no significant difference in OS was seen between the unifocal and multifocal groups (log-rank test: p = 0.93). However, the multifocal group exhibited a poorer prognosis in terms of RFS compared to the unifocal group (log-rank test: p = 0.004) Hereditary syndrome, tumor grade, size, lymphovascular invasion, and lymph node metastasis were key factors in the recurrence.

CONCLUSION

This study's findings suggest that the presence of multiple tumors was associated with poorer recurrence-free survival but did not affect long-term survival following surgery. Given the long-term oncologic outcome and quality of life following surgery, resection of tumors over 2 cm is advisable in patients with multifocal PNETs, while a cautious "wait-and-see" approach for smaller tumors (under 2 cm) can minimize the extent of resection and improve the quality of life. In cases with only small multifocal NF-PNETs (< 2 cm), immediate resection may not be crucial, but the higher recurrence rate than that in solitary NF-PNET necessitates intensified surveillance.

Current prospects of hereditary adrenal tumors: towards better clinical management

Adrenocortical carcinoma (ACC) and pheochromocytoma/paraganglioma (PPGL) are two rare types of adrenal gland malignancies. Regarding hereditary tumors, some patients with ACC are associated with with Li-Fraumeni syndrome (LFS), and those with PPGL with multiple endocrine neoplasia type 2. Recent studies have expanded this spectrum to include other types of hereditary tumors, such as Lynch syndrome or familial adenomatous polyposis. Individuals harboring germline TP53 pathogenic variants that cause LFS have heterogeneous phenotypes depending on the respective variant type. As an example, R337H variant found in Brazilian is known as low penetrant. While 50-80% of pediatric ACC patients harbored a LFS, such a strong causal relationship is not observed in adult patients, which suggests different pathophysiologies between the two populations. As for PPGL, because multiple driver genes, such as succinate dehydrogenase (SDH)-related genes, RET, NF1, and VHL have been identified, universal multi-gene germline panel testing is warranted as a comprehensive and cost-effective approach. PPGL pathogenesis is divided into three molecular pathways (pseudohypoxia, Wnt signaling, and kinase signaling), and this classification is expected to result in personalized medicine based on genomic profiles. It remains unknown whether clinical characteristics differ between cases derived from genetic predisposition syndromes and sporadic cases, or whether the surveillance strategy should be changed depending on the genetic background or whether it should be uniform. Close cooperation among medical genomics experts, endocrinologists, oncologists, and early investigators is indispensable for improving the clinical management for multifaceted ACC and PPGL.

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

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

Hereditary Renal Cancer Syndromes

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

IL-6-Producing Pheochromocytoma Associated With Von Hippel Lindau Disease: A Case Report With Literature Review

We present a first case report of an IL-6-producing pheochromocytoma associated with von Hippel Lindau (vHL) disease. Pheochromocytomas are rare tumors that produce catecholamines, leading to various symptoms. In this case, a 28-year-old woman with a family history of vHL disease presented with a prolonged fever. Laboratory examinations revealed elevated C-reactive protein levels, and notably, a significantly increased serum IL-6 level. Imaging studies confirmed bilateral adrenal tumors with increased uptake on fluorodeoxyglucose-positron emission tomography and 123I-metaiodobenzylguanidine scintigraphy in the right adrenal gland. Despite partial relief with nonsteroidal anti-inflammatory drugs and alpha-blockers, her fever persisted until prednisolone administration, which promoted a complete resolution. A histopathological analysis following a right laparoscopic adrenalectomy revealed a typical pheochromocytoma. We conducted further analyses, including an enzyme-linked immunosorbent assay (ELISA), a quantitative real-time polymerase chain reaction (PCR) test, and immunoblot assays from the resected tumor tissues. We compared the current case with other cases of pheochromocytoma that presented neither elevated serum IL-6 nor high fever. Using ELISA, we found that this patient exhibited more IL-6 secretion than that seen in other cases. Additionally, quantitative real-time PCR and immunoblot found that both the phosphorylated signal transducer and activator of transcription 3 (STAT3) messenger RNA (mRNA) and protein expression levels exceeded those of the other cases. Thus, we surmised that IL-6 was produced directly from the tumor tissue and IL-6 expression was potentiated through the IL-6/STAT3 signaling pathway. Our findings contribute to the understanding of IL-6-producing pheochromocytomas and their distinct clinical characteristics.

Early Screening and Identification of an Asymptomatic Pheochromocytoma in a Child with Von Hippel-Lindau: A Case Report

Introduction

Von Hippel-Lindau (VHL) is a diagnosis that leads to increased risk of tumor development over the course of a patient's lifetime. Patients with VHL undergo screening for multiple tumor types, including pheochromocytomas (PCCs). There is variability among the different international guidelines regarding the age to begin PCC screening, with most suggesting 5 years for screening initiation.

Case Presentation

Our patient is a 4-year-old female who underwent screening for PCC at the time of her VHL diagnosis while asymptomatic that identified a unilateral PCC. This was amendable to treatment with laparoscopic partial adrenalectomy.

Conclusion

This is the first report of an asymptomatic PCC being identified in a patient under the age of 5. With early identification, this was treated surgically before it caused systemic symptoms with preservation of normal adrenal gland tissue. This supports adhering to the pediatric specific guidelines which recommend earlier initiation of PCC screening in pediatric patients with VHL.

Case report: Obstructive azoospermia as the first presentation of Von Hippel-Lindau disease

We report the case of a 38-year-old man whose diagnostic workup for primary infertility led to the discovery of obstructive azoospermia due to bilateral papillary cystadenoma of the epididymis (PCE). Given the rarity of this finding and because PCE could be a manifestation of Von Hippel-Lindau disease (VHL), although the patient had no family or personal history of VHL, the VHL gene was tested, and a known pathogenetic variant (c.464-1G>A; p.)? was found. Screening for other Von Hippel-Lindau disease-associated neoplasms revealed bilateral retinal capillary hemangioblastomas, clear cell renal cell carcinoma, and multiple pancreatic cysts. In this case, an accurate diagnostic workup for male infertility allowed the detection of a rare life-threatening syndrome, already presenting with several silent neoplasms. For this reason, this case report may be useful for reproductive medicine specialists in the management of male infertility.

Epidemiology of Neuroendocrine Neoplasms and Results of Their Treatment with [177Lu]Lu-DOTA-TATE or [177Lu]Lu-DOTA-TATE and [90Y]Y-DOTA-TATE-A Six-Year Experience in High-Reference Polish Neuroendocrine Neoplasm Center

Neuroendocrine neoplasms (NENs) are a group of neoplasms arising from neuroendocrine cells. The worldwide incidence and prevalence of the NENs are estimated to be 6/100,000 and 35/100,000, respectively. Those numbers are increasing every decade, requiring higher and higher diagnosis and treatment costs. Radioligand therapy (RLT) using beta-emitting radioisotopes is an efficient and relatively safe method of treatment, typically used as a second-line treatment. RLT tolerability is higher than other available pharmacotherapies (chemotherapy or tyrosine kinase inhibitors). Recent studies show an increase in overall survival among patients treated with RLT. The present study aimed to learn the epidemiology of NENs in Poland and assess the effectiveness of RLT in a high-reference center. A prospective analysis of 167 patients treated with RLT in one of Poland's highest-reference NEN centers was performed. The analysis covered 66 months of observation (1 December 2017-30 May 2023), during which 479 RLT single administrations of radioisotope were given. The standard procedure was to give four courses of [177Lu]Lu-DOTA-TATE alone, or tandem therapy-[177Lu]Lu-DOTA-TATE and [90Y]Y-DOTA-TATE. Grading analysis showed that most patients had non-functioning G2 NEN with a mean Ki-67 of 6.05% (SD ± 6.41). The most common primary tumor location was the pancreas. Over two-thirds of patients did undergo surgery due to primary tumors or distant metastases. The majority of patients were using lanreotide as a chronically injected somatostatin analog. Median progression-free survival (PFS) on somatostatin analogs was 21.0 (IQR = 29.0) months. Directly after the last course of RLT, disease stabilization was noted in 69.46% of patients, partial regression was noted in 20.36% of patients, complete regression was noted in 0.60% of patients, and progression was noted in 9.58% of patients. In long-term follow-up, the median observation time among patients who underwent four treatment cycles (n = 108) was 29.8 (IQR = 23.9) months. Stabilization of the disease was observed in 55.56% of the patients and progression was observed in 26.85% of the patients, while 17.59% of patients died. Median PFS was 29.3 (IQR 23.9), and the median OS was 34.0 months (IQR 16.0). The mean age of NEN diagnosis is the sixth decade of life. It takes almost three years from NEN diagnosis to the start of RLT. In long-term observation, RLT leads to disease stabilization in over half of the patients with progressive disease. No differences in PFS or OS depend on the radioisotope used for RLT. In Poland, organized coordination of NEN treatment in high-reference centers ensures the continuity of patient care.

Anesthetic Challenge in a Parturient With Von Hippel-Lindau Disease

Von Hippel-Lindau (VHL) syndrome is a rare autosomal dominant disease with incomplete penetrance and variable expression. The features of cerebellar and spinal tumors, pheochromocytomas, and increased intracranial pressure complicate the anesthetic management of such patients. This report describes the anesthetic management of a parturient with VHL disease and highlights the importance of proper surveillance, vigilant management, and individualized treatment plans from a multidisciplinary team.

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.

Cystic Clear Cell Renal Cell Carcinoma: A Morphological and Molecular Reappraisal

A wide variety of renal neoplasms can have cystic areas. These can occur for different reasons: some tumors have an intrinsic cystic architecture, while others exhibit pseudocystic degeneration of necrotic foci or they have cystically dilated renal tubules constrained by stromal neoplastic cells. Clear cell renal cell carcinoma (CCRCC), either solid or cystic, is the most frequent type of renal cancer. While pseudocysts are found in high-grade aggressive CCRCC, cystic growth is associated with low-grade indolent cases. The latter also form through a cyst-dependent molecular pathway, and they are more frequent in patients suffering from VHL disease. The differential diagnosis of multilocular cystic renal neoplasm of low malignant potential and clear cell papillary renal cell tumor can be especially hard and requires a focused macroscopical and microscopical pathological analysis. As every class of renal tumor includes cystic forms, knowledge of the criteria required for a differential diagnosis is mandatory.

Non-Interventional Management of Advanced Pancreatic Neuroendocrine Neoplasms in Patients with von Hippel-Lindau Disease

Von Hippel-Lindau (VHL) is a rare autosomal dominant hereditary cancer predisposition syndrome. Patients with VHL have a high risk for developing retinal and central nervous system hemangioblastoma, pheochromocytoma, renal cell carcinoma, and pancreatic neuroendocrine neoplasms (PNEN). About a fifth of patients with VHL will develop PNEN, and only a tenth of them will develop metastatic or unresectable (advanced) PNEN requiring medical intervention. In this review, we performed a literature search for studies, written in English, on the medical interventions for VHL-related localized and advanced PNENs and their clinical outcomes. We detail the various medical interventions for this rare group of patients, including their mode of action and potential efficacy and toxicity. Finally, based on the current literature, we delineate a possible management algorithm for patients with VHL and advanced PNEN. We can conclude that data on the efficacy of various vascular endothelial growth factor (VEGF) receptor inhibitors, and on the efficacy of belzutifan, a novel hypoxia-inducible factor 2 inhibitor, for the management of advanced PNEN in VHL, are scarce. Hence, deduction from the management of sporadic PNEN is required, and is implemented in the proposed management algorithm provided within this review.

Unique Characteristics of Patients with Von Hippel-Lindau Disease Defined by Various Diagnostic Criteria

Von Hippel-Lindau (VHL) disease diagnosis is based on two criteria sets: International criteria (IC, two hemangioblastomas, one hemangioblastoma plus one visceral lesion, or VHL family history/pathogenic variant plus hemangioblastoma/visceral lesion); or Danish criteria (DC, two clinical manifestations, or VHL family history/pathogenic variant plus hemangioblastoma/visceral lesion). We aimed to compare the characteristics of patients with VHL-related pancreatic neuroendocrine tumor (vPNET) meeting either the clinical Danish criteria only (DOC) or IC to those with sporadic PNET (sPNET). The cohort included 33 patients with VHL (20 vPNETs) and 65 with sPNET. In terms of genetic testing and family history of VHL, 90.0% of the patients with vPNET in the IC group had a germline VHL pathogenic variant, and 70.0% had a family history of VHL vs. 20% and 10% in the DOC group, respectively (p < 0.05 for both). Patients with vPNET were younger at diagnosis compared with sPNET (51.6 ± 4.1 vs. 62.8 ± 1.5 years, p < 0.05). Patients in the IC group were younger at diagnosis with VHL, vPNET, pheochromocytoma, or paraganglioma (PPGL) and renal-cell carcinoma (RCC) than those in the DOC group (p < 0.05 for all comparisons). The most prevalent presenting manifestations were hemangioblastoma (42.8%) and PPGL (33.3%) vs. RCC (58.3%) and PNET (41.7%) in the IC vs. DOC groups. In conclusion, patients with vPNET meeting DOC criteria show greater similarity to sPNET. We suggest performing genetic testing, rather than solely using clinical criteria, for establishing the diagnosis of VHL.

Neuroendocrine neoplasms in the context of inherited tumor syndromes: a reappraisal focused on targeted therapies

PURPOSE

Neuroendocrine neoplasms can occur as part of inherited disorders, usually in the form of well-differentiated, slow-growing tumors (NET). The main predisposing syndromes include: multiple endocrine neoplasias type 1 (MEN1), associated with a large spectrum of gastroenteropancreatic and thoracic NETs, and type 4 (MEN4), associated with a wide tumour spectrum similar to that of MEN1; von Hippel-Lindau syndrome (VHL), tuberous sclerosis (TSC), and neurofibromatosis 1 (NF-1), associated with pancreatic NETs. In the present review, we propose a reappraisal of the genetic basis and clinical features of gastroenteropancreatic and thoracic NETs in the setting of inherited syndromes with a special focus on molecularly targeted therapies for these lesions.

METHODS

Literature search was systematically performed through online databases, including MEDLINE (via PubMed), and Scopus using multiple keywords' combinations up to June 2022.

RESULTS

Somatostatin analogues (SSAs) remain the mainstay of systemic treatment for NETs, and radiolabelled SSAs can be used for peptide-receptor radionuclide therapy for somatostatin receptor (SSTR)-positive NETs. Apart of these SSTR-targeted therapies, other targeted agents have been approved for NETs: the mTOR inhibitor everolimus for lung, gastroenteropatic and unknown origin NET, and sunitinib, an antiangiogenic tyrosine kinase inhibitor, for pancreatic NET. Novel targeted therapies with other antiangiogenic agents and immunotherapies have been also under evaluation.

CONCLUSIONS

Major advances in the understanding of genetic and epigenetic mechanisms of NET development in the context of inherited endocrine disorders have led to the recognition of molecular targetable alterations, providing a rationale for the implementation of treatments and development of novel targeted therapies.

Síndrome de von Hippel-Lindau em um Serviço Privado de Câncer em São Paulo: Relato de Caso

Introdução: A síndrome de von Hippel-Lindau (VHL) é uma patologia hereditária autossômica dominante que envolve o crescimento de tumores em diversas regiões do corpo humano em razão da mutação no gene VHL. Relato do caso: Paciente, sexo masculino, 38 anos, há três anos queixava-se de cefaleia recorrente, com piora progressiva. Foi diagnosticado com uma lesão em cerebelo cuja ressonância magnética cerebral encontrou uma formação expansiva na porção posteroinferior do hemisfério cerebelar esquerdo. Foi realizada tomografia multislice de abdome, que evidenciou formação nodular esplênica com realce marginal. A imagem da coluna cervical demonstrou pequeno nódulo localizado na medula cervical (intramedular) adjacente à vértebra cervical 3 (C3). Diante dos achados, o paciente foi submetido à ressecção macroscópica total da lesão do cerebelo, com laudo anatomopatológico de hemangioblastoma cerebelar grau 1, de acordo com a classificação da Organização Mundial da Saúde (OMS), que é um tumor benigno com baixa agressividade e recorrência. O teste imuno-histoquímico mostrou cluster of differentiation 34 (CD 34) positivo, índice de proliferação celular (Ki67) positivo (<5%), alfa inibina positiva e epithelial membrane antigen (EMA) negativo. Como o paciente não tinha história familiar de câncer, em função dos achados radiológicos, foi realizado sequenciamento de nova geração identificando a variante patogênica VHL c.292T>C, constatado em linhagem germinativa que, apesar do desconhecimento de história familiar positiva para a síndrome, confirmou o diagnóstico do paciente. Conclusão: O conjunto de achados clínicos e a variante no gene VHL confirmam o diagnóstico da síndrome.

Immunological Aspects of Von Hippel-Lindau Disease: A Focus on Neuro-Oncology and Myasthenia Gravis

Von Hippel-Lindau (VHL) disease is an autosomal dominant condition that predisposes affected individuals to a variety of malignant and benign neoplasms. The pathogenetic turning point of this illness is the accumulation of hypoxia-inducible factor (HIF)-1α, a transcription factor of several genes involved in oncogenesis, angiogenesis, tissue regeneration, metabolic regulation, hematopoiesis, and inflammatory responses. From an oncological perspective, increased awareness of the molecular pathways underlying this disease is bringing us closer to the development of specific and targeted therapies. Meanwhile, on the surgical side, improved understanding can help to better identify the patients to be treated and the surgical timing. Overall, pathogenesis research is crucial for developing patient-tailored therapies. One of the actual key topics of interest is the link between the VHL/HIF axis and inflammation. The present study aims to outline the fundamental mechanisms that link VHL disease and immune disorders, as well as to explore the details of the overlap between VHL disease and myasthenia gravis (MG) pathogenetic pathways. As a result, MG becomes a paradigm for autoimmune disorders that might be related with VHL disease.

[A Surgically Treated Depression]

A Surgically Treated Depression Abstract. We present a 64-year-old patient with an unclear deterioration of her general condition due to a suspected depression. Despite antidepressive treatment, her condition further deteriorated. The CT/MRI of the skull showed a cerebellar tumor as well as a hydrocephalus obstructivus. Together with tumor staging, the histology, which revealed a hemangioblastoma, led to the diagnosis of VHL syndrome. Patients with VHL syndrome and their families should be included in a screening program, unless molecular genetic testing has ruled out the disease.

Supratentorial Collision Tumor of Hemangioblastoma and Metastatic Clear Cell Renal Cell Carcinoma in a Patient with von Hippel-Lindau Disease

Collision tumors are rarely reported in patients with von Hippel-Lindau (VHL) disease, even though VHL patients often present with multi-organ tumor syndromes, like hemangioblastoma and renal cell carcinoma (RCC). Hemangioblastoma is rarely located in a supratentorial location, and intracranial lateral ventricular is also not a common site of metastasis for RCC. It is extremely rare for the two tumors to collide in the supratentorial area. We report a 64-year-old man with a history of clear cell RCC who presented with a sudden headache. The brain magnetic resonance imaging revealed that there was a cystic-solid mass in the intracranial lateral ventricular trigone. Histopathologically, the tumor consisted of two distinct components, most of which showed the typical morphology of hemangioblastoma. However, there were a few acinar structures composed of clear cells scattered in hemangioblastoma, and these acinar structures were subsequently confirmed as clear cell RCC. The genetic testing confirmed that the patient had VHL disease with de novo somatic mutation. Based on our case report, we systematically reviewed the characteristics of collision tumor composed of hemangioblastoma and metastatic RCC in VHL patients. The special growth site of our case is the first report of this kind of collision tumor, and can also help enrich our understanding of VHL disease and collision tumor.

Tumorigenesis Mechanisms Found in Hereditary Renal Cell Carcinoma: A Review

Renal cell carcinoma is a heterogenous cancer composed of an increasing number of unique subtypes each with their own cellular and tumor behavior. The study of hereditary renal cell carcinoma, which composes just 5% of all types of tumor cases, has allowed for the elucidation of subtype-specific tumorigenesis mechanisms that can also be applied to their sporadic counterparts. This review will focus on the major forms of hereditary renal cell carcinoma and the genetic alterations contributing to their tumorigenesis, including von Hippel Lindau syndrome, Hereditary Papillary Renal Cell Carcinoma, Succinate Dehydrogenase-Deficient Renal Cell Carcinoma, Hereditary Leiomyomatosis and Renal Cell Carcinoma, BRCA Associated Protein 1 Tumor Predisposition Syndrome, Tuberous Sclerosis, Birt-Hogg-Dubé Syndrome and Translocation RCC. The mechanisms for tumorigenesis described in this review are beginning to be exploited via the utilization of novel targets to treat renal cell carcinoma in a subtype-specific fashion.