Retinal hemangioblastoma. A histologic, immunohistochemical, and ultrastructural evaluation

ZEISS PLEX Elite 9000 Widefield Optical Coherence Tomography Angiography as Screening Method for Early Detection of Retinal Hemangioblastomas in von Hippel-Lindau Disease

Purpose

To evaluate early detection of retinal hemangioblastomas (RHs) in von Hippel-Lindau disease (VHLD) with widefield optical coherence tomography angiography (wOCTA) compared to the standard of care in ophthalmologic VHLD screening in a routine clinical setting.

Methods

We conducted prospective comparisons of three screening methods: wOCTA, standard ophthalmoscopy, and fluorescein angiography (FA), which was performed only in uncertain cases. The numbers of detected RHs were compared among the three screening methods. The underlying causes for the lack of detection were investigated.

Results

In 91 eyes (48 patients), 67 RHs were observed (mean, 0.74 ± 1.59 RH per eye). FA was performed in eight eyes. Ophthalmoscopy overlooked 25 of the 35 RHs detected by wOCTA (71.4%) due to the background color of the choroid (n = 5), small tumor size (n = 13), masking by a bright fundus reflex (n = 2), and masking by surrounding retinal scars (n = 5). However, wOCTA missed 29 RHs due to peripheral location (43.3%). The overall detection rates were up to 37% on the basis of ophthalmoscopy alone, up to 52% for wOCTA, and 89% for FA. Within the retinal area covered by wOCTA, the detection rates were up to 46.7% for ophthalmoscopy alone, up to 92.1% for wOCTA, and 73.3% for FA.

Conclusions

The overall low detection rate of RHs using wOCTA is almost exclusively caused by its inability to visualize the entire peripheral retina. Therefore, in unclear cases, FA is necessary after ophthalmoscopy.

Translational Relevance

Within the imageable retinal area, wOCTA shows a high detection rate of RHs and therefore may be suitable to improve screening for RHs in VHLD.

Retinal Glial Cells in Von Hippel-Lindau Disease: A Novel Approach in the Pathophysiology of Retinal Hemangioblastoma

Simple Summary

The in vivo optical coherence tomography analysis of the biomarkers of retinal microglia and macroglia in Von Hippel–Lindau disease represents an innovative field of research. The different behavior of these glial cells in Von Hippel–Lindau patients provides new data regarding the pathophysiology of retinal hemangioblastoma, the most common ocular manifestation of this hereditary disorder. Moreover, these biomarkers show a different behavior in Von Hippel–Lindau patients in relation to the presence or absence of retinal hemangioblastoma. Therefore, we can hypothesize that retinal hemangioblastoma is mainly due to the activation of macroglia by previously activated microglial cells.

Abstract

Background: Von Hippel–Lindau (VHL) disease is a neoplastic syndrome caused by a mutation of the VHL tumor suppressor gene. Retinal hemangioblastoma (RH) is a vascularized tumor and represents the most common ocular manifestation of this disease. At the retinal level, VHL protein is able to regulate tumor growth, angiogenic factors, and neuroinflammation, probably stimulating retinal glial cells. The aim of the present study was to analyze in vivo the optical coherence tomography (OCT) biomarkers of retinal macroglia and microglia in a cohort of VHL patients. Methods: The mean thicknesses of macular retinal nerve fiber layer (mRNFL), ganglion cell layer (GCL), and peripapillary retinal nerve fiber layer (pRNFL) were measured with OCT as biomarkers of retinal macroglia. OCT images were also analyzed to detect and quantify hyperreflective retinal foci (HRF), a biomarker of retinal activated microglia. Results: 61 eyes of 61 VHL patients (22 eyes (36.07%) with peripheral RH and 39 eyes (63.93%) without RH) and 28 eyes of 28 controls were evaluated. pRNFL was thinner in VHL patients (p < 0.05) and in VHL without RH (p < 0.01) compared to controls, and thicker in VHL patients with RH than in those without RH (p < 0.05). The thickness of mRNFL (p < 0.0001) and GCL (p < 0.05) was reduced in VHL patients and in VHL without RH compared to controls, whereas mRNFL (p < 0.0001) and GCL (p < 0.05) were increased in VHL patients with RH compared to those without RH. HRF were significantly higher in number in VHL patients and in VHL without RH, than in controls, and significantly lower (p < 0.05) in the eyes of VHL patients with RH, than in those without RH. Conclusions: The OCT analysis, which detects and allows to quantify the biomarkers of retinal microglia (HRF) and macroglia (pRNFL, mRNFL and GCL), showed a different behavior of these two retinal glial cells populations in VHL patients, related to the presence or absence of peripheral RH. These data allow to hypothesize a novel pathophysiologic pathway of retinal hemangioblastoma in VHL disease.

Structural and microvascular changes of the peripapillary retinal nerve fiber layer in Von Hippel-Lindau disease: an OCT and OCT angiography study

Von Hippel–Lindau (VHL) disease is an autosomal dominant genetic disease caused by VHL gene mutation. Retinal hemangioblastomas (RH) are vascularized tumors and represent the main ocular manifestation of the disease. Histopathologically, RH are composed of capillary vessels and stromal cells, the neoplastic population of the lesion. The origin of these stromal cells remains controversial, even if they are hypothesized to be glial cells. The aim of the present study was to investigate neuronal and microvascular changes of the peripapillary retinal nerve fiber layer, in which glial cells, neurons and capillaries (the radial peripapillary capillary plexus) interact. VHL patients with or without peripheral RH were enrolled and compared to healthy controls. Mean peripapillary retinal nerve fiber layer (pRNFL) thickness was measured by means of optical coherence tomography (OCT). The following vascular parameters of the radial peripapillary capillary plexus were quantified using OCT angiography: Vessel Area Density,Vessel Length Fraction, Vessel Diameter Index and Fractal Dimension. One hundred and nine eyes of 61 patients, and 56 eyes of 28 controls were consecutively studied. Mean pRNFL was significantly thinner in VHL eyes without RH versus eyes with RH and controls. Mean pRNFL thickness did not differ between VHL eyes with RH and controls. All OCTA vascular parameters were reduced in VHL eyes with or without RH versus controls, with significative difference for Vessel Diameter Index. The same OCTA parameters did not significantly differ between VHL eyes with or without RH. In VHL eyes without RH, pRNFL thinning may be the consequence of impaired perfusion of the radial peripapillary capillary plexus, while the increase of pRNFL thickness in VHL eyes with RH may depend on possible activation and proliferation of the other RNFL resident cells, the glial cells.

Insights into retinal hemangioblastoma using ultra widefield imaging

Purpose:

Retinal hemangioblastomas (RHs) are characteristic of von Hippel-Lindau (VHL) disease. Early diagnosis of retinal lesions may aid in systemic diagnosis. Early identification of VHL is life-saving and also prevents vision loss. Fundus fluorescein angiography (FFA) is a useful tool in the diagnosis and management of RHs. The aim of this study is to report FFA features of RH using ultra-widefield (UWF) imaging.

Methods:

A retrospective cross-sectional study of consecutive patients of RH who underwent UWF FFA at a tertiary eye care center. Images were analyzed and assessed by authors. The main outcome measures were (a) the number and size of RH in each eye and (b) vascular characteristics of the retina. UWF-FFA characteristics in each eye were tabulated. The number of clock hours involved by these characteristics and their correlation with the number and size of RH were analyzed.

Results:

The study evaluated 24 eyes of 13 patients. The mean age was 28.4 years. The median number of RHs in an eye was 3.5 (range 1–16), and the size of RHs varied from 0.1 to 4 disc diameters. Novel UWF-FFA findings noted in this study were the presence of abnormal capillary network in 22 of 24 eyes (91.7%), capillary leakage in 15 of 24 eyes (62.5%), and capillary telangiectasia in 7 of 24 eyes (29.2%). In addition, feeder arterioles and venules showed bulbous projections in 8 of 24 eyes (33.3%).

Conclusion:

The UWF-FFA characteristics of RH, which have not been described before, were identified. These add to our understanding of the pathogenesis of the disease and may pave the way for future therapeutic targets.

Detection of retinal microvascular changes in von Hippel-Lindau disease using optical coherence tomography angiography

PURPOSE

Von Hippel-Lindau (VHL) disease is a hereditary disorder that can lead to ophthalmic manifestations, including retinal capillary hemangioma (RCH). The diagnosis of RCH is often guided by wide-field fluorescein angiography. In some cases, optical coherence tomography angiography (OCT-A) serves as a non-invasive alternative to FA. Herein, we used OCT-A to examine the macular microvasculature in patients with VHL disease.

SUBJECTS

Subjects were selected from patients with a diagnosis of VHL. The control group included eyes without retinal diagnosis from patients with an episode of unilateral retinal detachment or trauma and age ≤ 50 years old.

METHODS

Subjects were scanned on the Optovue RTVue-XR device to acquire 3mm x 3mm OCT-A images of the superficial (SCP) and deep capillary plexus (DCP). SCP and DCP vessel density (VD) were calculated after the images were binarized. Furthermore, for subjects with RCH, each OCT-A image was divided equally into four quadrants. SCP and DCP VD of quadrants with RCH were compared to those without RCH. T-tests were performed for statistical analysis.

RESULTS

67 eyes with a history of VHL disease were included as study subjects, while 16 eyes were included as controls. Significant increases in VD were found in patients with VHL disease for both the SCP (p = 0.0441) and DCP (p = 0.0344). When comparing quadrants with associated RCH development to those without, we found no significant difference in SCP VD (p = 0.160) or DCP VD (p = 0.484).

CONCLUSIONS

OCT-A can detect changes in the retinal microvasculature in the macula of patients with VHL disease. OCT-A imaging may be an additional tool for screening and early detection of patients at risk of developing ocular complications of VHL disease. Future studies should explore subtle progression on OCT-A associated with the pathogenesis and development of RCH, particularly with larger scan patterns.

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.

Rb1/Rbl1/Vhl loss induces mouse subretinal angiomatous proliferation and hemangioblastoma

Von Hippel-Lindau (Vhl) protein inhibits hypoxia-inducible factor (Hif), yet its deletion in murine retina does not cause the extensive angiogenesis expected with Hif induction. The mechanism is unclear. Here we show that retinoblastoma tumor suppressor (Rb1) constrains expression of Hif target genes in the Vhl-/- retina. Deleting Rb1 induced extensive retinal neovascularization and autophagic ablation of photoreceptors in the Vhl-/- retina. RNA-sequencing, ChIP, and reporter assays showed Rb1 recruitment to and repression of certain Hif target genes. Activating Rb1 by deleting cyclin D1 induced a partial defect in the retinal superficial vascular plexus. Unexpectedly, removing Vhl suppressed retinoblastoma formation in murine Rb1/Rbl1-deficient retina but generated subretinal vascular growths resembling retinal angiomatous proliferation (RAP) and retinal capillary hemangioblastoma (RCH). Most stromal cells in the RAP/RCH-like lesions were Sox9+, suggesting a Müller glia origin, and expressed Lgals3, a marker of human brain hemangioblastoma. Thus, the Rb family limit Hif target gene expression in the Vhl-/- retina, and removing this inhibitory signal generates new models for RAP and RCH.

An Update on the Ophthalmologic Features in the Phakomatoses

Neurofibromatosis type 1, tuberous sclerosis complex, and Von Hippel-Lindau disease, historically classified as the phakomatoses, are hereditary multisystem disorders characterized by the presence of hamartoma, which carry the risk of malignant transformation. The alteration of tumor suppressor genes seems to be at the basis of their pathophysiogenetic mechanism. Lisch and choroidal nodules in neurofibromatosis type 1, retinal astrocytomas in tuberous sclerosis complex, and retinal capillary hemangioma in Von Hippel-Lindau disease are the principal ophthalmic hamartomatous manifestations. The advent of novel imaging techniques such as near infrared reflectance and optical coherence tomography has provided unprecedented insight on the choroidal and retinal features of these diseases. These methods have improved early diagnosis and the ongoing surveillance in these conditions. Among an array of treatment modalities, antivascular endothelial growth factor therapy has been used in the management of retinal hamartomas but results have been varied. This review is an update on the pathophysiogenetic mechanisms, ophthalmic manifestations, and novel treatment strategies in the phakomatoses with emphasis on the role of imaging techniques.

von Hippel-Lindau Disease: Review of Genetics and Imaging

von Hippel-Lindau (VHL) disease is an autosomal-dominant, hereditary, multisystem neoplasia syndrome with increased susceptibility to several benign and malignant tumors. VHL occurs in about 1 in 36,000 live births and is associated with germline mutation of the VHL tumor suppressor gene on the short arm of chromosome 3. VHL disease exhibits diverse genotype and phenotype correlations, exhibits variable intrafamilial and interfamilial expressivity, and can manifest with benign and malignant tumors of the central nervous system, kidneys, adrenals, pancreas, and reproductive organs. Imaging and management of this entity are therefore multidisciplinary. An overview of VHL disease is presented.

Atypical Exophytic Retinal Capillary Hemangioma and Diagnostic Modalities

PURPOSE

Retinal capillary hemangioma (RCH) can occur in isolation or may be associated with von Hippel-Lindau disease. The classic RCH is described as a globular reddish lesion with a dilated feeding artery and a tortuous draining vein, indicative of a common endophytic growth pattern. Exophytic patterns are far more rare and, because of its subtle appearance, often missed or misdiagnosed.

CASE REPORT

A 24-year-old woman presented with complaints of a mid-peripheral superior field defect OS. She had no family history of von Hippel-Lindau disease. Best-corrected visual acuity was 20/20 OD, OS. Dilated fundus examination of the left eye revealed a peripheral large inferotemporal retinal lesion with an overlying vascular network. Corresponding feeding and draining vasculature was not clearly noted on dilated fundus examination. Optical coherence tomography, ultrasonography, and fluorescein angiography testing were used to confirm the diagnosis of an exophytic peripheral RCH. Anti-vascular endothelial growth factor injections and cryotherapy were initiated, and the patient was scheduled for radioactive plaque brachytherapy. Genetic testing and proper scans were also recommended.

CONCLUSIONS

This case illustrates an atypical exophytic peripheral RCH, rarely reported in the literature. The utilization of a variety of diagnostic modalities was highly effective, aiding in the diagnosis of this condition.

Pathology characteristics of ocular von Hippel-Lindau disease with neovascularization of the iris and cornea: a case report

Introduction

Retinal hemangioblastoma is one of the most common tumors in von Hippel-Lindau disease. In addition to the classical pathological characteristics of von Hippel-Lindau disease, we report, for what we believe to be the first time, a severe and rare ocular complication characterized by neovascularization in the cornea and iris.

Case presentation

A 41-year-old white man with a long history of retinal hemangioblastoma presented with neovascularization of his iris and cornea as well as corneal perforation. His right eye was blind and painful, leading to a decision of enucleation. On microscopy, the enucleated eye showed neovascularization of the cornea and iris. The cornea was perforated with an expulsive hemorrhage and extruding intraocular contents, including the retina. A large retinal hemangioblastoma was located at the posterior pole adjacent to the optic nerve head. The tumor was mainly composed of large cells with foamy cytoplasm. Bone formation was also present.

Conclusion

Our pathology findings were consistent with previously described features of retinal hemangioblastoma. The present case is unusual because of the co-existing neovascularization in the iris and cornea, which may have led to corneal perforation and vision loss.

Intraocular astrocytoma and its differential diagnosis

Astrocytomas arising within the eye display 2 distinct histologies: one comprises interlacing bundles of spindle-shaped cells mixed with a minority of polygonal cells, and the other consists of large cells with abundant glassy cytoplasm (gemistocytic astrocytes) indistinguishable from cells found in subependymal giant cell astrocytoma. Both histologic patterns express glial fibrillary acid protein diffusely, are biologically benign, and are frequently associated with dysgenic syndromes, particularly tuberous sclerosis complex. Tumors with gemistocytes, however, demonstrate a greater propensity for invasive growth. The clinical history may provide information to guide the pathologist in distinguishing intraocular astrocytoma from reactive astrocytosis, conditions that are histologically similar. It remains to be determined if other types of primary intraocular glioma exist or whether some degree of ependymal or oligodendroglial differentiation can accompany reactive astrocytosis.

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.

Clinically unsuspected retinal hemangioblastoma in a blind eye as the initial manifestation of von Hippel-Lindau disease

We describe the microscopic findings of a clinically unsuspected retinal hemangioblastoma in an eye removed for pain and blindness. Although the patient was otherwise in good health, further investigation revealed von Hippel-Lindau (VHL) disease. Retinal hemangioblastomas are small benign tumors than can be easily overlooked in histological examination of an eye. Awareness of the context in which retinal hemangioblastoma can be found may be the most important factor in recognizing this lesion microscopically.

Central nervous system capillary haemangioblastoma: the pathologist's viewpoint

Haemangioblastomas are rare neoplasms of uncertain histogenesis. They represent 1.5-2.5% of intracranial tumours. While the cerebellum is by far the most frequent site, these lesions also tend to occur in the medulla and spinal cord. Most haemangioblastomas are sporadic but up to one quarter are associated with Von Hippel-Lindau disease (VHL). Although a fairly good number of haemangioblastomas were reported, a lack of side-by-side analysis of these reports has resulted in tentative conclusions that merely offer a first glimpse at their clinicopathologic diversity and histogenesis. To remedy this issue, this study presents a literature review concerning these lesions. Medline literature including both relevant monographs and clinicopathological case series. Haemangioblastomas occur either as a part of VHL disease (25-30%, inherited mutation of VHL gene on 3p25-26 chromosome) or as sporadic tumours (often with somatic mutation of VHL gene). They have diverse clinicopathologic presentations with cerebellar lesions having a better prognosis than their brainstem counterparts. Immunostaining is important for separation of haemangioblastomas from other tumours with similar histology. The rich vascularity of haemangioblastomas is due to overexpression of vascular endothelial growth factors. Moreover, 'stromal' cells represent the neoplastic cells of haemangioblastomas and are capable of forming blood islands with extramedullary haematopoiesis.

Molecular pathology of eyes with von Hippel-Lindau (VHL) Disease: a review

BACKGROUND

von Hippel-Lindau Disease (VHL) is an autosomal dominant inherited systemic cancer syndrome. Recently, many advances have contributed to the understanding of VHL pathophysiology.

METHODS

In this article we review recent developments and summarize our findings in VHL molecular pathology related to retinal and optic nerve diseases.

RESULTS

Loss of heterozygosity (LOH) within the VHL gene is detected in the stromal cells surrounding the capillary endothelial cells and admixed with glial cells in ocular hemangioblastomas. This finding is in line with similar findings in VHL-associated CNS hemangioblastoma and renal clear cell carcinomas. Increases of vascular endothelial growth factor (VEGF), hypoxia induced factor (HIF), and ubiquitin are found in ocular hemangioblastomas.Interestingly, tumorlet cells, which are composed of poorly differentiated small cells with prominent dark nuclei and little cytoplasm, as well as several stem cell markers, such as erythropoietin (Epo), Epo receptor (EpoR), and CD133, are present in ocular VHL lesions. CXCR4, a CXC chemokine receptor is also expressed in retinal VHL hemangioblastomas.

CONCLUSIONS

These findings imply that VHL cells with LOH of the tumor suppressor gene, most likely originate from a hematopoietic/vascular lineage. Targeting these proteins and ischemic factors, not VEGF alone, may be a potential therapeutic approach for VHL-associated ocular hemangioblastomas.

Retinal angioma associated with von Hippel-Lindau disease

Von Hippel-Lindau disease is a multi-system disorder that can produce hamartomas (benign tumour-like nodules) of the eyes, skin and nervous system. Retinal capillary angioma is a common ocular association of this congenital phakomatosis that may result in blinding sequelae, if not managed appropriately. We present a case of retinal angioma associated with von Hippel-Lindau disease and discuss the ocular and systemic signs, diagnosis and management. The optometrist is of particular importance in screening for this disorder, as it is often first detected in a routine eye examination.

Retinal function in the von Hippel-Lindau disease

PURPOSE

To assess the retinal function in patients with von Hippel-Lindau disease (VHL).

PATIENTS

Studies were undertaken in 12 patients (17 eyes) with detected VHL gene mutation and 12 normal healthy controls (17 eyes).

METHODS

Pattern ERG (PERG), standard flash electroretinogram (ERG) recordings were performed in accordance with the International Society for Clinical Electrophysiology of Vision (ISCEV) standards.

RESULTS

In VHL patients, electrophysiological statistically significant changes were found. In PERG examination, increased latency of P50 was found in the total VHL group (p < 0.02) and in the VHL subgroup with retinal angiomas (p < 0.04). In ERG examination, photopic b-wave latency was increased in the total VHL group (p < 0.03) and also in the VHL subgroup without retinal angiomas (p < 0.05). In OPs, latency increase of OP2, OP3 waves and reduced amplitude of OP3 wave in the total VHL group (OP2 latency, p < 0.05; OP3 latency, p < 0.01; OP3 amplitude, p < 0.03) and in the VHL subgroup with retinal angiomas (OP2 latency, p < 0.02; OP3 latency, p < .008; OP3 amplitude, p < 0.02) were obtained.

CONCLUSIONS

It can be hypothesized that dysfunction of the inner retinal layer is present in individuals with VHL disease even in patients without retinal angiomas.

Molecular basis of the VHL hereditary cancer syndrome

The von Hippel-Lindau hereditary cancer syndrome was first described about 100 years ago. The unusual clinical features of this disorder predicted a role for the von Hippel-Lindau gene (VHL) in the oxygen-sensing pathway. Indeed, recent studies of this gene have helped to decipher how cells sense changes in oxygen availability, and have revealed a previously unappreciated role of prolyl hydroxylation in intracellular signalling. These studies, in turn, are laying the foundation for the treatment of a diverse set of disorders, including cancer, myocardial infarction and stroke.

von Hippel-Lindau disease

In recent years advances have been made in the clinical and genetic aspects of von Hippel-Lindau disease (VHL). Retinal capillary hemangioma is the most common manifestation of VHL disease and, therefore, ophthalmologists are frequently involved in the care of patients with this disease. The incidence of VHL disease is approximately 1 in 40,000 live births. It is estimated that there are approximately 7000 patients with VHL disease in the USA. The inheritance of VHL disease is autosomal dominant with high penetrance. Depending on the clinical circumstances, retinal capillary hemangioma may be managed by observation, laser photocoagulation, cryotherapy, and plaque radiotherapy. Typical extraocular lesions associated with VHL disease are central nervous system hemangioma, renal cyst, renal carcinoma, pancreatic cysts and adenoma, pancreatic islet cell tumors, pheochromocytoma, endolymphatic sac tumor of the inner ear, and cystadenoma of the epididymis and the broad ligament. The life expectancy of affected individuals may be improved by early detection and treatment of varied manifestations with the use of surveillance protocols. Identification of the VHL gene on chromosome 3p25-26 has now made it possible for suspected individuals to undergo genetic testing with a high degree of accuracy. We review herein the ophthalmic manifestations and treatment of retinal capillary hemangioma and systemic findings of the VHL disease.

The eye in von Hippel-Lindau disease. Long-term follow-up of screening and treatment: recommendations

Von Hippel-Lindau disease (VHL) is an autosomal dominant tumour syndrome caused by germline mutations of the VHL tumour suppressor gene located on chromosome 3p25-26. In VHL tumours may occur in 14 different target organs, including the eye. Retinal angiomas are considered the first manifestation of VHL disease in 43% of cases, and the cumulative probability of developing a retinal angioma in one or both eyes rises during each decade of life, reaching 80% for patients over 80 years old. Since 1976 patients with VHL at the University Hospital of Utrecht and their at-risk relatives have been screened periodically by a multidisciplinary team. Long-term follow-up ophthalmological data were analysed with special attention to natural course and results of treatment. In addition, we looked for a genotype-phenotype correlation. Retinal angiomas were found in all families. In one large family with a missense mutation (V170D) of the VHL gene, in which the complete spectrum of visceral- and central nervous system (CNS) features of VHL is present, macular, parapapillary, optic disc and ora serrata angiomas were also found. In general, however, a clear-cut genotype-phenotype correlation could not be found. Only early detection and treatment of peripheral retinal angiomas can be expected to decrease the percentage of patients with decreased visual acuity. Therefore, early detection and treatment of these tumours is of paramount importance. Ophthalmological screening of patients and persons at risk should start as early as possible. In patients with apparently sporadic retinal angiomas it is advisable to perform germline DNA analysis, since the risk of developing VHL is high, especially if the angiomas are bilateral, or unilateral and multifocal, if the patient is young, or if there is a family history suggestive of VHL.

von Hippel-Lindau disease

von Hippel-Lindau disease is a hereditary cancer syndrome characterized by the development of vascular tumors of the central nervous system and retina, clear cell renal carcinomas, pheochromocytomas, pancreatic islet cell tumors, endolymphatic sac tumors, and benign cysts affecting a variety of organs. VHL disease is caused by germline mutations of the von Hippel-Lindau tumor suppressor gene located on chromosome 3p25. Tumor development in this setting is due to inactivation or loss of the remaining wild-type allele in a susceptible cell. The highly vascular nature of VHL-associated neoplasms can be understood in light of the recent finding that the VHL gene product (pVHL) inhibits the accumulation of hypoxia-inducible mRNAs, such as the mRNA encoding vascular endothelial growth factor (VEGF), under normoxic conditions. This property of pVHL appears to be linked to its ability to bind to complexes containing elongin B, elongin C, and cullin 2 (Cul2). Elongin C and Cul2, based on their homology with Skp1 and Cdc53, respectively, are suspected of targeting certain proteins for covalent modification with ubiquitin and hence for degradation. One model, which remains to be tested, is that the binding of pVHL to elongins B/C and Cul2 affects the ubiquitination of RNA-binding proteins that regulate the stability of hypoxia-inducible mRNAs.

Metastatic adenocarcinoma to the retina in a patient with Muir-Torre syndrome

PURPOSE/METHODS

A 74-year-old woman had multiple tumors including a retinal mass. Her medical history included cutaneous sebaceous adenomas, adenocarcinoma of the breast, and colonic adenocarcinoma. Her involved eye became painful and was enucleated.

RESULTS/CONCLUSIONS

Examination of the enucleated eye disclosed metastatic adenocarcinoma to the retina with retinal detachment. The patient described has a retinal metastasis of an unknown primary tumor site with Muir-Torre syndrome, characterized by an association of a sebaceous gland tumor with an internal malignancy.

von Hippel-Lindau disease manifesting as a chiasmal syndrome

A 21-year-old woman presented with a two year history of progressive loss of vision in the left eye. Brain MRI revealed a supresellar mass felt to be most consistent with a meningioma. However, pathologic examination including special stains disclosed features characteristic of hemangioblastoma. Further evaluation established the diagnosis of von Hippel-Lindau disease by demonstrating retinal capillary hemangiomas, small renal and hepatic cysts, and cervico-medullary masses later confirmed to be hemangioblastomas. To date, no other family members have displayed features of this inherited syndrome.