Genotype-phenotype correlation in von Hippel-Lindau disease with retinal angiomatosis

Surgical and visual outcomes after vitreoretinal surgery for complex retinal capillary hemangioblastoma

Purpose

We evaluated the anatomical and functional outcomes after vitreoretinal surgery for complex retinal capillary hemangioblastoma (RCH).

Methods

This was a retrospective case series of 15 patients (16 eyes) with tractional or combined retinal detachment (RD) managed with pars plana vitrectomy and tumor endoresection (ER) with/without feeder vessel ligation.

Results

The mean age at the time of surgery was 30 years (range, 14-46 years). The most common tumor locations were inferotemporal (six eyes) and temporal (six eyes) quadrants. Indications for surgery included exudative RD with fibrovascular proliferation (eight eyes), combined RD (five eyes), vitreous hemorrhage (four eyes), and rhegmatogenous RD (two eyes). Tumor destruction was performed with laser and/or cryotherapy in nine eyes (57%) and ER in seven eyes (43%). Feeder vessel was ligated and cauterized in 10 (63%) and six eyes (37%), respectively. Anatomical success after initial surgery was 50% (eight eyes), which improved to 88% (14 eyes) after they underwent a repeat procedure for recurrent RD (eight eyes). At the last visit, visual acuity improved in seven eyes (44%), was stable in four eyes (25%), and worsened in five eyes (31%) with a mean follow-up of 29 months (6-79 months). Comparison between the ER group and the laser/cryotherapy group revealed no significant difference in final retinal reattachment rate (89% vs. 86%, P > 0.05), with better visual outcomes in laser/cryotherapy group (57% vs. 78%, P < 0.05).

Conclusion

Pars plana vitrectomy with/without tumor endoresection can be a safe and effective treatment option for complex RCHs, achieving good tumor control and anatomical success with limited functional success.

Diseases of Hereditary Renal Cell Cancers

Germline mutations in tumor suppressor genes and oncogenes lead to hereditary renal cell carcinoma (HRCC) diseases, characterized by a high risk of RCC and extrarenal manifestations. Patients of young age, those with a family history of RCC, and/or those with a personal and family history of HRCC-related extrarenal manifestations should be referred for germline testing. Identification of a germline mutation will allow for testing of family members at risk, as well as personalized surveillance programs to detect the early onset of HRCC-related lesions. The latter allows for more targeted and therefore more effective therapy and better preservation of renal parenchyma.

Investigation of germline VHL variants in Iranian patients with retinal capillary hemangioblastoma and genotype-phenotype analysis

BACKGROUND

Retinal capillary hemangioblastoma (RCH), while sporadic in some cases, is the most common and earliest manifestation of von Hippel-Lindau disease (VHL). This is the first report on different types of VHL variants and genotype-phenotype correlations in Iranian families with RCH.

MATERIALS AND METHODS

In this prospective observational case series study, 17 families with RCH were included. PCR was performed to amplify 3 exons of VHL gene. Afterward, Sanger sequencing was performed on all PCR products. For the detection of VHL copy number variations, MLPA was used.

RESULTS

Our study identified 10 different types of VHL variants. Missense mutations were the most common variants found and affected the structure of α domain of the VHL protein (pVHL). The majority of mutations (72.7%) in the patients with RCH and central nervous system hemangioblastoma (CNS-HB) were located on α domain.

CONCLUSION

α domain of VHL may play a potential role in the pathogenesis of RCH. Our findings suggest that genotype-phenotype characteristics in those variants in α- domain may predispose patients to RCH with CNS-HB.

Clinical and Genetic Characteristics of Retinal Capillary Hemangioblastoma in Korean Patients

PURPOSE

We investigated the clinical features of Korean patients with retinal capillary hemangioblastoma (RCH) and genetic variants of the von Hippel-Lindau (VHL) gene.

METHODS

A retrospective analysis was performed on patients with RCH from 2003 to 2021 at Seoul National University Bundang Hospital. Sporadic and hereditary RCH associated with VHL disease were classified based on the specific tumors and family history. Clinical features, including the location and number of RCH and bilateral involvement, were investigated. Multiplex ligation-dependent probe amplification and direct sequencing targeting the VHL gene were performed for six RCH cases associated with VHL disease.

RESULTS

A total of 18 patients (23 eyes) were enrolled in this study. The mean age at diagnosis was 37 ± 15 years. Twelve patients had hereditary RCH associated with VHL disease, and six patients had sporadic RCH. All five patients with bilateral RCH were clinically diagnosed with VHL disease, and 13 patients had unilateral RCH. Juxtapapillary RCH was only observed in patients with VHL. The most common complication of RCH was the epiretinal membrane, followed by the subretinal fluid. Pathogenic variants were identified in four patients. All three patients with type 1 VHL had the well-known missense mutation p.Glu70Lys, and one patient with type 2 VHL had the nonsense mutation p.Trp88Ter.

CONCLUSIONS

In Korean patients with RCH, bilateral involvement and juxtapapillary RCH are highly likely to be associated with VHL disease. Because RCH may be the first clinical manifestation in patients with VHL, active genetic testing of the VHL gene and systemic evaluation are required.

Retinal hemangioblastoma in a patient with Von Hippel-Lindau disease: A case report and literature review

BACKGROUND

Retinal hemangioblastoma (RH) is a rare benign tumor and a considerable number of which are caused by Von Hippel-Lindau disease (VHL). Herein, we described a case of VHL-associated RH with retinal detachment who underwent both laser photocoagulation and vitreoretinal surgery and received satisfactory visual recovery. In addition, we reviewed the current diagnosis, genotype-phenotype association, and treatment of VHL-associated RH.

CASE DESCRIPTION

A 34-year-old woman presented with vision loss in the right eye at our hospital. Fundus photography and angiography showed retinal detachment and multiple large hemangiomas in the right eye. The visual acuity improved significantly after laser photocoagulation and vitreoretinal surgery. Genetic analyses showed a p.Asn78Ser (c.233A>G) heterozygous missense mutation in the VHL gene.

CONCLUSION

We described a rare case of VHL-associated RH and may provide a new perspective towards diagnosis and treatment of this disease. RH is one of the most common manifestations of VHL and poses a serious threat to vision. Ophthalmic examination methods include fundus examination and fundus photography, etc. The management of the disease emphasizes timely follow-up, early detection of the lesion, and the decision of treatment options according to the size, location and complications of the lesion, including ablation therapy and vitreoretinal surgery. Clinicians should strengthen the understanding of this rare disease for early detection and treatment.

A meta-analysis of different von Hippel Lindau mutations: are they related to retinal capillary hemangioblastoma?

Retinal capillary hemangioblastomas (RCH) is a benign tumor that represents the initial manifestation in roughly half of Von Hippel Lindau (VHL) patients. They may also occur sporadically without systemic involvement. A first meta-analysis study was investigated to estimate the prevalence of Retinal capillary hemangioblastoma (RCH) in Von Hippel Lindau (VHL) syndrome, and its relation to type and location of mutations in VHL gene. The electronic databases of PubMed, Scopus, Embase, and Google Scholar were utilized to find eligible papers published up to May 2020. Lastly, after the different prevalence of RCH in Europe compared to other continents was noted, we decided to consider European and non-European patients separately. The Random effect model was used to evaluate the relation between developing RCH and types of mutations. The overall prevalence of RCH among VHL patients is about 47%. The prevalence of RCH was significantly higher in Europe in comparison with non-Europeans (p value < 0.001). Overall, the differences between the prevalence of RCH among different mutation types were not statistically significant. However, in Europe, the prevalence of RCH was significantly higher in patients with truncation mutation (p value = 0.007). In Europe, the RCH in VHL patients who had a mutation in exon 2 was significantly lower in comparison with exon 1 (p value = 0.001); but in non-Europeans, the prevalence of RCH in VHL patients that involved exon 2 was significantly higher in comparison with VHL patients with a mutation in exon1 (p value = 0.012). The highest risk of developing RCH was reported among Europeans. Overall, this study showed that the prevalence of RCH in VHL syndrome is not related to type or location of mutations and difference of RCH prevalence is probably depends on other genetic or environmental factor that should be considered in subsequent studies.

The Role of VHL in the Development of von Hippel-Lindau Disease and Erythrocytosis

Von Hippel-Lindau disease (VHL disease or VHL syndrome) is a familial multisystem neoplastic syndrome stemming from germline disease-associated variants of the VHL tumor suppressor gene on chromosome 3. VHL is involved, through the EPO-VHL-HIF signaling axis, in oxygen sensing and adaptive response to hypoxia, as well as in numerous HIF-independent pathways. The diverse roles of VHL confirm its implication in several crucial cellular processes. VHL variations have been associated with the development of VHL disease and erythrocytosis. The association between genotypes and phenotypes still remains ambiguous for the majority of mutations. It appears that there is a distinction between erythrocytosis-causing VHL variations and VHL variations causing VHL disease with tumor development. Understanding the pathogenic effects of VHL variants might better predict the prognosis and optimize management of the patient.

Genotype-phenotype correlation in von Hippel-Lindau disease

BACKGROUND/AIMS

Retinal haemangioblastomas (RH) remain a major cause of visual impairment in patients with von Hippel-Lindau (VHL) disease. Identification of genotype-phenotype correlation is an important prerequisite for better management, treatment and prognosis.

METHODS

Retrospective, single-centre cohort study of 200 VHL patients. Genetic data and date of onset of RH, central nervous system haemangioblastomas (CNSH), pheochromocytoma/paraganglioma (PPGL), clear cell renal cell carcinoma (ccRCC) and pancreatic neuroendocrine neoplasm (PNEN) were collected. The number and locations of RH were recorded.

RESULTS

The first clinical finding occurred at an age of 26 ± 14 years (y) [mean ± SD]. In 91 ± 3% (95% CI 88-94) of the patients, at least one RH occur until the age of 60y. A total of 42 different rare VHL gene variants in 166 patients were detected. A higher age-related incidence of RH, CNSH, ccRCC and PNEN was detected in patients with a truncating variant (TV) compared to patients with a single amino-acid substitution/deletion (AASD) (all p < 0.01), while it is reverse for PPGL (p < 0.01). Patients with a TV showed 0.10 ± 0.15 RH per y during their lifetime compared to 0.05 ± 0.07 in patients with AASD (p < 0.02). The median enucleation/phthisis-free survival time in patients with a TV was 56y (95% CI 50-62) compared to 78y (95% CI 75-81) in patients with AASD (p < 0.02).

CONCLUSION

Compared to patients with AASD, patients with a TV develop RH, CNSH, ccRCC and PNEN earlier. They experience a higher number of RH and bear a higher risk of enucleation/phthisis. Thus, patients with a TV might be considered for a more intensive ophthalmological monitoring.

Outcome and genetic analysis of patients affected by retinal capillary hemangioblastoma in von Hippel Lindau syndrome

Purpose

To describe genetic analysis, treatment results, and complications of patients affected by retinal capillary hemangioblastoma (RCH) in von Hippel Lindau (VHL) syndrome.

Methods

We collected 17 patients with VHL syndrome, who underwent a molecular test and an ophthalmic evaluation at the Eye Clinic of the University Hospital of Florence from January 2005 to February 2020. We focused on eyes showing RCHs examined using color fundus photographs, fluorescein angiography, and optical coherence tomography.

Results

Eight eyes of six patients (6/17; 35%) showed RCHs at the fundoscopic examination. All RCHs were treated with laser therapy. Three eyes underwent episcleral surgery, one eye showing vitreous hemorrhage received three intravitreal (IV) anti-VEGF injections and three cryotherapy procedures, and one eye underwent vitrectomy. In patients with RCHs, five were characterized by a truncating mutation of the VHL protein, and one patient showed a missense mutation. We have reported two VHL mutations not reported in literature.

Conclusions

Patients with multiple RCHs, who developed RCH secondary effects, showed truncating mutations of the VHL protein. We recommend early screening and close monitoring, especially if RCHs are detected at presentation, for every patient with VHL syndrome independently of the results of the molecular test for a missense or a truncating mutation in VHL.

Von Hippel-Lindau disease and rapidly progressing pheochromocytomas in siblings

Von Hippel-Lindau (VHL) disease is an autosomal dominant inherited condition with a predisposition to the development of a variety of tumors including pheochromocytomas. A number of cancer surveillance protocols for patients with VHL have been developed, all of which are based on expert opinion. We report a case of two brothers with a strong family history of VHL type 2 due to a pathogenic germline VHL variant, specifically, a surface missense substitution, with a rapidly progressive clinical course that both presented with a large adrenal mass. Both brothers presented with large pheochromocytomas, the earliest presentation being at age 7, despite routine screening. The rapid progression and early presentation of these patients raises an important discussion around the commonly used surveillance protocols for pheochromocytoma in pediatric patients with VHL and missense mutations. We conclude that a more accelerated surveillance protocol may be adequate for VHL families with a high pheochromocytoma risk.

Ophthalmological Aspects of von-Hippel-Lindau Syndrome

Background: von Hippel-Lindau (VHL) syndrome is a multisystem neoplastic disorder involving eyes, central nervous system, kidneys, spine, and other tissues. A retinal capillary hemangioma (RCH) is the earliest manifestation of the VHL disease in most cases.Areas covered:This paper aims to provide an up-to-date review of the current literature about von Hippel-Lindau syndrome. Molecular background, systemic and ocular features of the diseases as well as the utility of newer imaging modalities in diagnosis and monitoring of ocular VHL disease have been described. Besides, we have discussed newer treatment modalities and therapeutic targets.Conclusion: Modern imaging technologies like optical coherence tomography and optical coherence tomography angiography are tools of the trade, in making an appropriate diagnosis and monitoring disease activity and response to treatment. Peripheral RCH may be treated using laser photocoagulation in tumors up to 3000 µm. Vascular endothelial growth factor suppression can help in reducing tumor activity and stabilize the tumor size; however, it does not regress the RCH.

Retinal haemangioblastomas in von Hippel-Lindau germline mutation carriers: progression, complications and treatment outcome

PURPOSE

Evaluation of phenotype and treatment outcome of retinal haemangioblastomas (RH) in von Hippel-Lindau (VHL) disease and correlation of these features with the genotype of VHL germline mutation carriers.

METHODS

Retrospective analysis of a longitudinal cohort of 21 VHL germline mutation carriers and RH. Clinical and genetic data were obtained to analyse the correlation of genotype with phenotype and treatment outcomes.

RESULTS

All patients were categorized in two genotypic categories: missense mutations (MM) and truncating mutations (TM). Mean follow-up duration was 16.3 years and did not differ significantly between mutation groups (p = 0.383). Missense mutations (MM) carriers (n = 6) developed more progression-related complications compared to TM carriers (n = 15) (p = 0.046). Vitreoretinal surgery was more often applied in MM carriers (p = 0.036). Moderate (visual acuity (VA)20/80 to 20/200) to severe (VA < 20/200) visual impairment was observed in 53.3% of the eyes of MM carriers and 28.1% of the eyes of TM carriers at last recorded visit.

CONCLUSION

Missense mutations in VHL patients seem to have a higher prevalence of progression-related complications. Missense mutations (MM) carriers required therefore more often vitreoretinal surgical treatment with a worse treatment outcome. Genetic analysis may play a role in determining a pro-active treatment strategy and prognosis for RH.

Von Hippel-Lindau Disease and the Eye

Retinal hemangioblastoma (also referred to as retinal capillary hemangioma) is a benign lesion originating from the endothelial and glial components of the neurosensory retina and optic nerve head. Historically known as a manifestation of the von Hippel-Lindau (VHL) disease, it can be seen as an isolated finding or in association with some rare ocular conditions. In addition to characteristic ophthalmoscopic features, results of numerous ancillary tests including angiography, ultrasound, optical coherence tomography, and genetic tests may support the diagnosis and differentiate it from similar conditions. Because of serious life-threatening complications of VHL disease, every ocular approach to retinal hemangioblastomas should be in relationship with additional multidisciplinary diagnostic and therapeutic efforts. In addition, any patient with actual or probable diagnosis of VHL disease should be screened for ocular involvement. Unfavorable visual loss can occur early, and ocular complications of VHL range from exudative retinopathy to tractional retinal detachment, neovascular glaucoma, and phthisis bulbi. Accordingly, various treatment methods have been tested with overall acceptable responses, including photocoagulation, cryotherapy, photodynamic therapy, plaque radiotherapy, vitrectomy, and more novel intravitreal injections of anti-vascular endothelial growth factors and propranolol.

Difficulties in the management of retinal capillary haemangiomas associated with von Hippel Lindau disease

CLINICAL CASE

A 29-year-old female with bilateral retinal capillary haemangiomas (RCH). A genetic analysis was carried out due to the suspicion of von Hippel-Lindau (VHL) disease, with negative results on 2occasions. There was progression of the RCH in the left eye, leading to a macular epiretinal membrane. The patient was treated with laser, intravitreal ranibizumab, and vitrectomy. Finally, a third genetic test detected a de novo mutation in the VHL gene, and led to the genetic diagnosis.

DISCUSSION

VHL syndrome causes a complex ocular disease with a difficult diagnosis that requires early treatment of the RCH in order to modify its visual prognosis.

Posterior Pole and Peripheral Retinal Fibrovascular Proliferation in von Hippel Lindau Disease

PURPOSE

To report the occurrence of fibrovascular proliferation (FVP) in the retina in von Hippel-lindau (VHl) patients and its association with prior treatment.

DESIGN

A retrospective study.

METHODS

A retrospective study of 101 VHL patients. Fundus photos were available for 28 patients. FVP was classified into peripheral and posterior pole.

RESULTS

All 28 patients had retinal capillary hemangioblastomas (RCH) in 1 or both eyes; 15 patients were found to have FVP (group A), whereas 13 patients did not (group B). Mean age of patients in group A was 35 ± 11.3 years and 36.6 ± 13.8 in group B (P = 0.74). In group A, 27 eyes had RCH; 21 (77.77%) had FVP. In group B, 19 eyes had RCH. The number of treated eyes was significantly higher in group A (81.48%) than group B (42.1%) (P = 0.007). In group A, FVP was noted in the posterior pole in 9 eyes, in the periphery in 5 eyes, and 7 eyes developed both posterior pole and peripheral FVP.

CONCLUSIONS

FVP can occur in the peripheral retina and in the posterior pole. There is a significant association between prior treatment of RCH and the occurrence of FVP.

SPONTANEOUS RESOLUTION OF MACULAR EPIRETINAL MEMBRANES AFTER FLUORESCEIN POTENTIATED ARGON LASER TREATMENT OF VON HIPPEL-LINDAU ASSOCIATED RETINAL HEMANGIOMAS: CASE REPORT AND REVIEW OF LITERATURE

PURPOSE

To illustrate spontaneous resolution of macular epiretinal membranes and inactivation of retinal hemangioma exudation after fluorescein potentiated argon laser treatment of bilateral capillary hemangiomas in a patient with a de novo heterozygous deletion in Exon 2 of the von Hippel-Lindau gene.

METHODS

Interventional case report.

RESULTS

A 23-year-old man with subjective complaints of blurry vision, photophobia, and glare. On presentation, visual acuity was 20/20 in the right eye and 20/25 in the left eye with metamorphopsia. On the basis of bilateral retinal hemangiomas on clinical examination and characterization with multimodal imaging, a diagnosis of von Hippel-Lindau disease was made. Genetic testing identified a de novo, disease-causing heterozygous deletion in Exon 2 of the von Hippel-Lindau gene. The patient underwent 4 sessions of fluorescein potentiated 532 nm argon green laser treatment directed at retinal hemangiomas. No adverse sequelae of laser treatment were noted. Seven months after the initial presentation, the patient's vision was 20/20 in both eyes with interval resolution of metamorphopsia. There was spontaneous resolution of a macular epiretinal membrane with normalization of the macular retinal microstructure. The retinal hemangiomas in both eyes appeared inactive, and no new lesions were noted.

CONCLUSION

Fluorescein potentiated argon laser successfully treated bilateral retinal hemangiomas in our patient with von Hippel-Lindau disease. Additional studies to characterize the full clinical potential of fluorescein potentiated argon laser therapy may be warranted.

Clinical and molecular characteristics of East Asian patients with von Hippel-Lindau syndrome

Background

Von Hippel–Lindau (VHL) syndrome is a dominantly inherited multisystem cancer syndrome caused by a heterozygous mutation in the VHL tumor suppressor gene. Previous studies suggested that similar populations of Caucasian and Japanese patients have similar genotype or phenotype characteristics. In this comprehensive study of East Asian patients, we investigated the genetic and clinical characteristics of patients with VHL syndrome.

Methods

To create a registry of clinical characteristics and mutations reported in East Asian patients with VHL syndrome, we conducted a comprehensive review of English language and non-English language articles identified through a literature search. Publications in Japanese or Chinese language were read by native speakers of the language, who then performed the data extraction.

Results

Of 237 East Asian patients with VHL syndrome, 154 unique kindreds were identified for analysis. Analyzed by kindred, missense mutations were the most common (40.9%, 63/154), followed by large/complete deletions (32.5%, 50/154) and nonsense mutations (11.7%, 18/154). Compared with a previously reported study of both East Asian and non-East Asian patients, we found several key differences. First, missense and frameshift mutations in the VHL gene occurred less commonly in our population of East Asian patients (40.9% vs. 52.0%; P = 0.012 and 8.4% vs. 13.0%; P < 0.001, respectively). Second, large/complete deletions were more common in our population of East Asian patients (32.5% vs. 10.5%; P < 0.001). Third, phenotypically, we observed that, in our population of East Asian patients with VHL syndrome, the incidence of retinal capillary hemangioblastoma was lower, whereas the incidence of renal cell carcinoma was higher.

Conclusions

Evidence suggests that the genotypic and phenotypic characteristics of East Asian patients with VHL syndrome differ from other populations. This should be considered when making screening recommendations for VHL syndrome in Asia.

Electronic supplementary material

The online version of this article (doi:10.1186/s40880-016-0141-z) contains supplementary material, which is available to authorized users.

Von Hippel-Lindau disease: the clinical manifestations and genetic analysis results of two cases from a single family

von Hippel-Lindau (VHL) disease is an autosomal dominant inherited multi systemic cancer syndrome that is classically associated with neoplasms in multiple organs, and caused by mutations in the VHL gene on chromosome 3p25-p26. Retinal hemangioblastoma (RH) is the most frequent and the earliest clinical sign of the disease, which is seen in 40.0-60.0% of patients. In recent years, studies of patients with VHL tried to put forward the relationship between genotype and phenotype. In this study, two VHL cases in the same family with clinical findings and genetic analysis results are presented. As a consequence of the genetic studies, a heterozygous missense mutation c.202 T>C, p.S68P (Ser68Pro) in exon 1 of the VHL gene that is mapped to chromosome 3p25.3, was found in the patients’ DNA sample. The germline mutation of [c.202T>C, p.S68P (Ser68Pro)] that was detected in both cases, has been reported in only two cases in the literature. However, in these reported cases, any systemic involvement except RH, were not reported. Although our cases had the same mutation, we detected renal involve-ment in both cases, and also central nervous system (CNS) involvement in one case, in addition to RH.

Genotype-phenotype correlations, and retinal function and structure in von Hippel-Lindau disease

PURPOSE

To investigate genotype-phenotype correlation and to analyze functional and structural changes in the retina of patients with von Hippel-Lindau (VHL) disease.

METHODS

Thirteen patients from four families (A, B, C and D) with known VHL disease and known mutations in the VHL gene were examined. All patients underwent clinical examination and optical coherence tomography (OCT). Full-field electroretinography (full-field ERG) was performed in twelve patients.

RESULTS

Family A, with deletion of exon 3 in the VHL gene, and family B, with the missense mutation p.R79P, exhibited type 1 VHL characterized by the absence of pheochromocytoma and a high incidence of central nervous system hemangioblastomas. One member of family B exhibited Goldenhar syndrome. A novel missense mutation (p.L198P) was identified in the VHL gene in the patient from family C. This p.L198P mutation caused a phenotype with early onset of a neuroendocrine tumor of the pancreas, bilateral pheochromocytomas, and optic nerve hemangioblastoma. Full-field ERG showed significantly prolonged implicit times of the b-wave and maximal combined a-wave in VHL patients, compared to controls. Examination of the retinal structure in all patients with VHL, using OCT, showed a significant decrease in retinal thickness in VHL patients without ocular hemangioblastomas, compared to controls.

CONCLUSIONS

Our findings support previously established genotype-phenotype correlations. However, we here describe an unusual phenotype with a novel missense mutation, p.L198P, and report the finding that VHL disease can be associated with Goldenhar syndrome. Electrophysiological and structural findings suggest that VHL disease is a progressive, neurodegenerative disease of the retina.

The metabolic basis of kidney cancer

Kidney cancer is not a single disease; it is made up of a number of different types of cancer that occur in the kidney. Each of these different types of kidney cancer can have a different histology, have a different clinical course, can respond differently to therapy and is caused by a different gene. Kidney cancer is essentially a metabolic disease; each of the known genes for kidney cancer, VHL, MET, FLCN, TSC1, TSC2, TFE3, TFEB, MITF, fumarate hydratase (FH), succinate dehydrogenase B (SDHB), succinate dehydrogenase D (SDHD), and PTEN genes is involved in the cells ability to sense oxygen, iron, nutrients or energy. Understanding the metabolic basis of kidney cancer will hopefully provide the foundation for the development of effective forms of therapy for this disease.

Longitudinal analysis of retinal hemangioblastomatosis and visual function in ocular von Hippel-Lindau disease

OBJECTIVE

Characterization of the structural and functional progression of ocular von Hippel-Lindau (VHL) disease and analysis of patient factors influencing disease progression.

DESIGN

Retrospective analysis of a case series from a longitudinal, observational study.

PARTICIPANTS

Two hundred forty-nine participants with clinically defined systemic VHL disease and more than 2 years of ophthalmic follow-up.

METHODS

Standardized scoring of ocular phenotype and systemic characteristics was performed at each study visit and was analyzed longitudinally to determine progression of ocular VHL disease.

MAIN OUTCOME MEASURES

Measures evaluated include: visual acuity, features of ocular VHL disease (presence, location, number, and extent of retinal capillary hemangioblastomas [RCHs]), germline mutation in the VHL gene, demographics (age, gender, age at onset of ocular disease), and patient characteristics (smoking status, body mass index).

RESULTS

Most participants demonstrated relative anatomic and functional stability in ocular VHL disease status over a mean follow-up of 8.2 ± 4.0 years. Approximately three quarters (73%) of participants without ocular VHL disease at baseline remained disease free at the end of follow-up. Among eyes with ocular VHL disease at baseline, 88% did not demonstrate RCHs in a new retinal location, 70% remained stable in RCH number, and 79% remained stable in the extent of RCH involvement. Mean visual acuity for all study eyes (n = 498) decreased by 5.1 ± 0.6 letters across follow-up, with 16.1% of study eyes decreasing by more than 10 letters in visual acuity. Among eyes affected at baseline, greater vision loss was associated with the presence of juxtapapillary RCHs, development of RCH in a new location, and increase in peripheral RCH number and extent. Younger baseline age, younger age at onset of ocular VHL disease, involvement of the fellow eye with ocular VHL disease, and missense or protein-truncating germline mutations were associated significantly with increased anatomic involvement and functional deterioration.

CONCLUSIONS

Patients with ocular VHL disease maintain relative anatomic and functional stability, with only a minority demonstrating marked anatomic progression and vision loss. Systemic and ocular risk factors for anatomic progression and vision loss can help practitioners identify patients with a higher risk profile for counseling, closer follow-up, and proactive treatment.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Von Hippel-Lindau disease (VHL): a need for a murine model with retinal hemangioblastoma

Von Hippel-Lindau (VHL) disease is a highly penetrant autosomal dominant systemic malignancy that gives rise to cystic and highly vascularized tumors in a constellation of organs. Patients with VHL disease commonly present with hemangioblastomas in the central nervous system and the eye while other manifestations include pheochromocytoma, clear cell renal cell carcinoma, endolymphatic sac tumors of the middle ear, pancreatic cystadenomas, epididymal and broad ligament cystadenomas. Animal models inactivating the VHL gene product in various organ tissues have been constructed over the past 15 years to parse its HIF-associated mechanisms and its link to tumorigenesis. These models, despite advancing our understanding the molecular role of VHL, are by and large unable to recapitulate the more common features of human VHL disease. Up to date, no model exists that develop retinal hemangioblastomas, the most common clinical manifestation. The purpose of this review is: (1) to discuss the need for an ocular VHL model, (2) to review the animal models that recapitulate clinical VHL disease and (3) to propose potential mechanisms of tumorigenesis for the development of ocular VHL.

[Von Hippel-Lindau disease: family study]

CASE REPORT

The case of 5 members of a family who suffer from Von Hippel-Lindau disease (VHL) is presented. It is shown that retinal capillary hemangioma was the main ophthalmic symptom, with hemovitreous and tractional retinal detachment as the main complications.

DISCUSSION

VHL disease is rare, but very serious, even fatal, thus it is important to obtain an early diagnosis by ophthalmoscopy, in order to change the visual prognosis and life expectancy, not only for the patient, but also for the family.

Knowledge of hereditary renal cancer syndromes: a pending issue for oncologists

Renal cell cancer (RCC) is a rare disease that accounts for 2-3% of all solid malignancies. Although its etiology is not known, approximately 4% of RCC occurs in the context of complex hereditary syndromes in which the kidney lesions are associated with other manifestations. Therefore, clinical suspicion is essential for proper diagnosis and management. In this review a practical summary to aid treating physicians in the identification of hereditary RCC syndromes, including von Hippel-Lindau syndrome, hereditary papillary RCC, Birt-Hogg-Dubé syndrome, and hereditary leiomyomatosis RCC, is provided. Early recognition of these specific populations will lead to better care, correct surveillance, and, in the near future, to personalized treatment taking advantage of underlying genetic defects.

Vitreoretinal surgery for severe retinal capillary hemangiomas in von hippel-lindau disease

PURPOSE

To evaluate the long-term success rate of vitreoretinal surgery for severe cases of retinal capillary hemangiomas (RCHs) caused by von Hippel-Lindau (VHL) disease.

DESIGN

Retrospective case series.

PARTICIPANTS

Twenty-three eyes of 21 patients with severe exudative or tractional retinal detachment caused by RCH, who had undergone vitreoretinal surgery. Patients' age at initial surgery ranged from 12 to 47 years (median, 27 years), and the fellow eye was already blind in 6 of 21 patients.

INTERVENTIONS

All eyes underwent pars plana vitrectomy with posterior hyaloid detachment epiretinal membrane dissection and silicone oil or gas injection. In 9 eyes, retinectomy was performed to remove the RCH (group R). In the other 14 eyes, the RCH was treated by laser endophotocoagulation alone or combined with transscleral cryotherapy (group L).

MAIN OUTCOME MEASURES

Visual acuity (preoperative, 6 and 18 months postoperatively), rate of RCH recurrence, and postoperative complications.

RESULTS

In group R, an average of 2 operations per patient was needed. Six months after surgery, the retina was flat in 8 eyes. Mean follow-up was 8 years. Long-term complications included RCH reproliferation and neovascular glaucoma in 4 eyes, 4 to 8 years after initial surgery. In the remaining 5 eyes, visual acuity ranged from 20/320 to counting fingers 18 months postoperatively. In group L, an average of 1.7 operations was needed. Six months after surgery, the retina was flat in 13 of 14 eyes. Mean follow-up was 4 years. New RCH occurred in 10 eyes and required laser treatment. In the long term, 1 eye became blind after 5 years because of aggressive RCH reproliferation and neovascular glaucoma, and 2 eyes became blind after 10 years because of exudative retinal detachment. In the 11 remaining eyes, visual acuity ranged from 20/320 to 20/20 (median: 20/50) 18 months postoperatively.

CONCLUSIONS

Vitreoretinal surgery is an effective treatment for severe VHL retinal hemangiomas. Large RCHs were satisfactorily treated by (1) vitrectomy with epiretinal dissection and endolaser photocoagulation or (2) retinectomy for RCH resection, although a high rate of vision-threatening RCH recurrence was observed in the long term. However in most cases, surgery improved or prolonged visual function in these eyes.

von Hippel-Lindau tumor suppressor mutants faithfully model pathological hypoxia-driven angiogenesis and vascular retinopathies in zebrafish

Biallelic inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene predisposes human patients to the development of highly vascularized neoplasms in multiple organ systems. We show that zebrafish vhl mutants display a marked increase in blood vessel formation throughout the embryo, starting at 2 days post-fertilization. The most severe neovascularization is observed in distinct areas that overlap with high vegfa mRNA expression, including the vhl mutant brain and eye. Real-time quantitative PCR revealed increased expression of the duplicated VEGFA orthologs vegfaa and vegfab, and of vegfb and its receptors flt1, kdr and kdr-like, indicating increased vascular endothelial growth factor (Vegf) signaling in vhl mutants. Similar to VHL-associated retinal neoplasms, diabetic retinopathy and age-related macular degeneration, we show, by tetramethyl rhodamine-dextran angiography, that vascular abnormalities in the vhl−/− retina lead to vascular leakage, severe macular edema and retinal detachment. Significantly, vessels in the brain and eye express cxcr4a, a marker gene expressed by tumor and vascular cells in VHL-associated hemangioblastomas and renal cell carcinomas. VEGF receptor (VEGFR) tyrosine kinase inhibition (through exposure to sunitinib and 676475) blocked vhl−/−-induced angiogenesis in all affected tissues, demonstrating that Vegfaa, Vegfab and Vegfb are key effectors of the vhl−/− angiogenic phenotype through Flt1, Kdr and Kdr-like signaling. Since we show that the vhl−/− angiogenic phenotype shares distinct characteristics with VHL-associated vascular neoplasms, zebrafish vhl mutants provide a valuable in vivo vertebrate model to elucidate underlying mechanisms contributing to the development of these lesions. Furthermore, vhl mutant zebrafish embryos carrying blood vessel-specific transgenes represent a unique and clinically relevant model for tissue-specific, hypoxia-induced pathological angiogenesis and vascular retinopathies. Importantly, they will allow for a cost-effective, non-invasive and efficient way to screen for novel pharmacological agents and combinatorial treatments.

Genotype-phenotype correlation in ocular von Hippel-Lindau (VHL) disease: the effect of missense mutation position on ocular VHL phenotype

PURPOSE

von Hippel-Lindau (VHL) disease is a dominantly inherited, multisystemic tumor syndrome caused by mutations in the VHL gene. This study was conducted to establish genotype-phenotype correlations between the positions of disease-causing missense mutations and the ocular phenotypes of VHL disease.

METHODS

Participants with clinically defined VHL disease and documented germline missense mutations in the VHL gene were identified in a cross-sectional study (n=412). Statistical analysis was used to correlate the position of the missense mutation in either the alpha- or beta-domain of the VHL protein with the ocular disease phenotype.

RESULTS

Missense mutations among study participants were located in 47 of the 213 possible codons in the VHL gene. Almost all mutations (98.5%) were located in one of two structural domains of the VHL protein: the alpha- and beta-domains. alpha-Domain mutations were significantly associated with a higher prevalence of retinal capillary hemangioblastomas (RCHs) compared with the beta-domain mutations (P=0.016). Among patients with RCHs, the prevalence of the lesions in the juxtapapillary position was also significantly higher in patients with alpha-domain mutations (P=0.0017). Conversely, beta-domain mutations correlated with a higher prevalence of peripherally located RCHs (P=0.0104).

CONCLUSIONS

The location of missense mutations in the VHL gene correlates significantly with the prevalence and phenotype of ocular disease, and as such, influences the risk of visual loss in affected patients. These genotype-phenotype correlations can assist in the prognostic counseling and follow-up of VHL patients and may provide a basis for molecular inferences on ocular VHL disease pathogenesis.

Within-Cluster Resampling for Analysis of Family Data: Ready for Prime-Time?

Hoffman et al. [1] proposed an elegant resampling method for analyzing clustered binary data. The focus of their paper was to perform association tests on clustered binary data using within-cluster-resampling (WCR) method. Follmann et al. [2] extended Hoffman et al.'s procedure more generally with applicability to angular data, combining of p-values, testing of vectors of parameters, and Bayesian inference. Follmann et al. [2] termed their procedure multiple outputation because all "excess" data within each cluster is thrown out multiple times. Herein, we refer to this procedure as WCR-MO. For any statistical test to be useful for a particular design, it must be robust, have adequate power, and be easy to implement and flexible. WCR-MO can be easily extended to continuous data and is a computationally intensive but simple and highly flexible method. Considering family as a cluster, one can apply WCR to familial data in genetic studies. Using simulations, we evaluated WCR-MO's robustness for analysis of a continuous trait in terms of type I error rates in genetic research. WCR-MO performed well at the 5% α-level. However, it provided inflated type I error rates for α-levels less than 5% implying the procedure is liberal and may not be ready for application to genetic studies where α levels used are typically much less than 0.05.

Hereditary kidney cancer: unique opportunity for disease-based therapy

Kidney cancer is not a single disease; it is comprised of several different types of cancer, each with a different histology, with a different clinical course, caused by a different gene, and responding differently to therapy. The VHL gene is the gene for the hereditary cancer syndrome, von Hippel-Lindau, as well as for the common form of sporadic, noninherited, clear cell kidney cancer. Understanding the VHL-hypoxia inducible factor (HIF) pathway has provided the foundation for the development of several agents targeting this pathway, such as sunitinib, sorafenib, and temsirolimus. Hereditary papillary renal carcinoma (HPRC) is a hereditary renal cancer syndrome in which affected individuals are at risk for the development of bilateral, multifocal, type 1 papillary renal cell carcinoma. The genetic defect underlying HPRC is MET, the cell surface receptor for hepatocyte growth factor. Mutations of MET also have been identified in a subset of tumors from patients with sporadic type 1 papillary renal cell carcinoma (RCC). Clinical trials targeting the MET pathway are currently underway in patients with HPRC and in patients with sporadic (nonhereditary) papillary kidney cancer. The BHD gene (also known as folliculin or FLCN) is the gene for Birt-Hogg-Dube syndrome, an autosomal-dominant genodermatosis associated with a hereditary form of chromophobe and oncocytic, hybrid RCC. Preclinical studies are underway targeting the BHD gene pathway in preparation for clinical trials in Birt-Hogg-Dube and sporadic chromophobe RCC. Patients with hereditary leiomyomatosis RCC (HLRCC) are at risk for developing cutaneous and uterine leiomyomas and a very aggressive type of RCC. HLRCC is characterized by germline mutation of the Krebs cycle enzyme, fumarate hydratase (FH). Studies of the tricarboxylic acid cycle and the VHL-HIF pathways have provided the foundation for therapeutic approaches in patients with HLRCC-associated kidney cancer as well as other hereditary and sporadic forms of RCC.

Intravitreal ranibizumab therapy for retinal capillary hemangioblastoma related to von Hippel-Lindau disease

PURPOSE

To evaluate the effect of intravitreal ranibizumab on retinal capillary hemangioblastomas (RCHs) associated with von Hippel-Lindau (VHL) disease that are not amenable or responsive to standard therapy.

DESIGN

Prospective, noncomparative, interventional case series.

PARTICIPANTS

Five patients with VHL-associated RCH with exudative changes and visual loss.

METHODS

Monthly intravitreal injections of ranibizumab (0.5 mg) were given over a course of 6 months for a total of 7 injections, with additional injections considered until week 52. The final study visit was designated as 8 weeks after the final study injection.

MAIN OUTCOME MEASURES

The primary outcome was the change in best-corrected visual acuity (BCVA) of >/=15 letters at the final visit compared with baseline. Secondary outcomes included change in lesion size, exudation as assessed clinically and by fluorescein angiography, change in retinal thickness as evaluated by optical coherence tomography, and adverse event assessments.

RESULTS

Patients received an average of 10.0+/-3.1 injections over an average period of 47+/-14 weeks, including follow-up. Mean change in BCVA was a decrease of 9+/-20 letters, with 1 patient gaining >/=15 letters, and 2 patients losing >/=15 letters. Changes in both lesion size and exudation were variable.

CONCLUSIONS

Intravitreal ranibizumab, delivered as monotherapy every 4 weeks, had minimal beneficial effects on most VHL-related RCHs. Possible treatment efficacy was demonstrated in the patient with the smallest lesion with less exudation. Future prospective studies are needed to determine the potential role of an antiangiogenic agent, possibly in combination with other therapies for the treatment of such advanced ocular tumors associated with VHL.

Ocular von Hippel-Lindau disease: clinical update and emerging treatments

PURPOSE OF REVIEW

von Hippel-Lindau disease is an inherited, multisystemic cancer syndrome often involving the retina. This review will provide an update for the clinical characterization and treatment of ocular von Hippel-Lindau disease.

RECENT FINDINGS

A comprehensive and quantitative clinical characterization of ocular von Hippel-Lindau disease has been limited by small patient numbers and nonrepresentative sampling. Recently, a large population of patients with clinically and genetically defined von Hippel-Lindau disease was systemically characterized in a single center, enabling a quantitative evaluation of the ocular involvement of this syndrome. Correlations between the nature of von Hippel-Lindau gene mutations and the ocular phenotype were also examined, providing clues as to how disruptions in von Hippel-Lindau protein function may result in eye disease. This understanding may be relevant to the development of new therapies targeting the molecular biology of von Hippel-Lindau disease, some of which are presently being investigated.

SUMMARY

Quantitative studies enable a full characterization of the impact of von Hippel-Lindau disease on eye health and visual function. Establishing correlations between the genotype of the von Hippel-Lindau mutation and the phenotype of eye disease may inform us as to how ocular von Hippel-Lindau disease arises, and help guide molecular interventions in ocular von Hippel-Lindau disease.

Retinal vascular proliferation as an ocular manifestation of von Hippel-Lindau disease

OBJECTIVES

To describe the features, natural history, and management of an unusual manifestation of ocular von Hippel-Lindau disease in the form of fine vascular proliferation.

METHODS

Case series of 14 patients with definite or presumed von Hippel-Lindau disease.

RESULTS

Retinal vascular proliferation consisting of fine superficial vessels was found in 16 eyes of 14 patients with von Hippel-Lindau disease. The lesion was often found in a juxtapapillary location and associated with a fibrovascular component and/or a macular epiretinal membrane. In cases with follow-up (12 patients; mean [SD] follow-up, 10.9 [7.5] years), the lesion was stable in 7 of 13 eyes but showed growth and progression resulting in vision loss in the remainder. In 5 eyes, surgical intervention with pars plana vitrectomy, membrane peel, and excision of the fibrovascular lesion resulted in visual improvement in all of the cases.

CONCLUSIONS

Ocular von Hippel-Lindau disease can uncommonly manifest as vascular proliferation that consists of fine, superficial, juxtapapillary vessels that are often associated with fibrovascular proliferation and epiretinal membrane formation. The natural history of this lesion is variable and can result in vision loss from tractional effects in progressive cases. Vision-threatening cases may be successfully managed by surgical excision.

Deletions at the SOX10 gene locus cause Waardenburg syndrome types 2 and 4

Waardenburg syndrome (WS) is an auditory-pigmentary disorder that exhibits varying combinations of sensorineural hearing loss and abnormal pigmentation of the hair and skin. Depending on additional symptoms, WS is classified into four subtypes, WS1-WS4. Absence of additional features characterizes WS2. The association of facial dysmorphic features defines WS1 and WS3, whereas the association with Hirschsprung disease (aganglionic megacolon) characterizes WS4, also called "Waardenburg-Hirschsprung disease." Mutations within the genes MITF and SNAI2 have been identified in WS2, whereas mutations of EDN3, EDNRB, and SOX10 have been observed in patients with WS4. However, not all cases are explained at the molecular level, which raises the possibility that other genes are involved or that some mutations within the known genes are not detected by commonly used genotyping methods. We used a combination of semiquantitative fluorescent multiplex polymerase chain reaction and fluorescent in situ hybridization to search for SOX10 heterozygous deletions. We describe the first characterization of SOX10 deletions in patients presenting with WS4. We also found SOX10 deletions in WS2 cases, making SOX10 a new gene of WS2. Interestingly, neurological phenotypes reminiscent of that observed in WS4 (PCWH syndrome [peripheral demyelinating neuropathy, central dysmyelinating leukodystrophy, WS, and Hirschsprung disease]) were observed in some WS2-affected patients with SOX10 deletions. This study further characterizes the molecular complexity and the close relationship that links the different subtypes of WS.