Ophthalmological manifestations in VHL and NF 1: pathological and diagnostic implications

Brachytherapy for Peripheral Retinal Capillary Haemangioblastoma in von Hippel-Lindau Disease

AIM

To report our experience with ¹⁰⁶ruthenium-brachytherapy of peripheral capillary haemangioblastomas in patients with von Hippel-Lindau disease.

DESIGN

Retrospective case series.

METHODS

A total of 53 haemangioblastomas, treated with ¹⁰⁶ruthenium-brachytherapy, were included in our study. The applied radiation dose, visual outcome, angioma activity, need for vitreoretinal surgery and incidence of secondary complications such as macular oedema, secondary glaucoma, vitreous haemorrhage, and epiretinal gliosis were assessed.

RESULTS

All treated eyes could be preserved. In 11 patients (20.8%), single brachytherapy did not achieve complete inactivation of the tumour. 31% developed macular oedema postoperatively. Tractional retinal detachment developed in 23.8%, and epiretinal gliosis was observed in 2.4% of patients. Vitreoretinal surgery was necessary in 50% of all treated eyes. At the end of the follow-up, 40.5% of all treated eyes achieved visual acuity (VA) of 0.6 or better, and one third reached a VA of less than 0.1. Mean irradiation dose to the tumour apex was 144 Gy. Higher apex doses correlated with better tumour control of irradiated haemanigoblastomas and lower complication rates.

CONCLUSIONS

Brachytherapy of peripheral retinal capillary haemangioblastomas is an effective treatment modality. Higher irradiation doses seem to lead to more successful treatment.

Germline Pathogenic Variants Identified by Targeted Next-Generation Sequencing of Susceptibility Genes in Pheochromocytoma and Paraganglioma

The aim of this study was to evaluate germline variant frequencies of pheochromocytoma and paraganglioma targeted susceptibility genes with next-generation sequencing method. Germline DNA from 75 cases were evaluated with targeted next-generation sequencing on an Illumina NextSeq550 instrument. KIF1B, RET, SDHB, SDHD, TMEM127, and VHL genes were included in the study, and Sanger sequencing was used for verifying the variants. The pathogenic/likely pathogenic variants were in the VHL, RET, SDHB, and SDHD genes, and the diagnosis rate was 24% in this study. Three different novel pathogenic variants were determined in five cases. This is the first study from Turkey, evaluating germline susceptibility genes of pheochromocytoma and paraganglioma with a detection rate of 24% and three novel variants. All patients with pheochromocytoma and paraganglioma need clinical genetic testing with expanded targeted gene panels for higher diagnosis rates.

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

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

Von Hippel-Lindau Disease: The Importance of Retinal Hemangioblastomas in Diagnosis

Von Hippel-Lindau (VHL) disease is a familial cancer syndrome characterized by benign or malignant tumors which may involve more than one system. Retinal hemangioblastomas are usually the initial manifestation of VHL disease and can cause vision loss. A 32-year-old man presented to our clinic with vision loss in the left eye for 2 months. He had a history of cerebral hemangioblastoma operation. Family history showed that his mother had unilateral vision loss and died because of renal cell carcinoma. Ophthalmologic examination revealed multiple retinal hemangioblastomas in both eyes. VHL gene sequencing was performed and heterozygous p.R161X mutation was detected. His sister and daughter were also found to have the same variant. A treatment and follow-up plan was initiated for the patient and affected family members. Considering VHL disease in the differential diagnosis of retinal hemangioblastomas has a very important role in the early detection of life-threatening tumors in these patients.

A Comprehensive Review of Pediatric Tumors and Associated Cancer Predisposition Syndromes

An understanding of the role of inherited cancer predisposition syndromes in pediatric tumor diagnoses continues to develop as more information is learned through the application of genomic technology. Identifying patients and their relatives at an increased risk for developing cancer is an important step in the care of this patient population. The purpose of this review is to highlight various tumor types that arise in the pediatric population and the cancer predisposition syndromes associated with those tumors. The review serves as a guide for recognizing genes and conditions to consider when a pediatric cancer referral presents to the genetics clinic.

Mechanical Ptosis in Neurofibromatosis Type 1 Heralding the Diagnosis of Right Sided Cervical Vagus Nerve Neurofibroma: A Rare Case Report

Neurofibromatosis type 1 (NF1) is an autosomal dominant, multisystem disorder. In NF1, involvement of vagus nerve can occur in the form of neurofibroma. A few cases of neurofibroma of thoracic vagus nerve have been reported while neurofibroma of cervical vagus nerve with NF1 is quite rare. A 19-year-old male came with complaints of decreased vision of both eyes and right sided drooping of eyelid since childhood. He was diagnosed as having NF1 with neurofibroma of right cervical vagus nerve.

Renal cancer in von Hippel-Lindau disease and related syndromes

Sporadic and hereditary forms of renal cell carcinoma (RCC), von Hippel-Lindau (VHL) disease and the familial paraganglioma syndromes are closely related in terms of their clinical, molecular, and genetic aspects. Most RCCs occur sporadically and the heritable fraction of RCC is estimated to be just 2-4%. An understanding of the molecular genetic basis, the disease-specific and gene-specific biology and the clinical characteristics of these cancer syndromes is of utmost importance for effective genetic diagnosis and appropriate treatment. In addition, such insight will improve our understanding of sporadic RCCs. To date, 10 different heritable RCC syndromes have been described. VHL syndrome is the oldest known hereditary RCC syndrome. Similar to VHL disease, phaeochromocytoma is a major manifestation of the paraganglioma syndromes types 1, 3 and 4 in which RCCs have been reported. These syndromes are therefore regarded as VHL-related disorders and are included in this Review. Multifocal tumours, bilateral occurrence, a young age at diagnosis and/or family history are clinical red flags suggestive of hereditary disease and should trigger referral for genetic and molecular analysis. The identification of an underlying genetic alteration enables gene-specific risk assessment and opens up the possibility of a tailored follow-up strategy and specific surveillance protocols as the basis of effective preventive medicine. The important goals of preventive medicine are to increase the life expectancy of affected patients and to improve their quality of life. The study of seemingly rare hereditary syndromes and their susceptibility genes has consistently revealed clues regarding the aetiology and pathogenesis of these diseases, and can aid diagnosis and the development of therapeutics for patients affected by much more common sporadic counterparts.

Ciliary body cysts in neurofibromatosis: a new coexistence?

PURPOSE

Neurofibromatosis 1 (NF1) is an autosomal dominant, multisystem disorder that also effects the eye. Herein, we aimed to investigate the posterior iris surface and ciliary body morphology of NF1 patients by ultrasonic biomicroscopy (UB).

MATERIALS & METHODS

Nine consecutive unrelated subjects with NF1, and as a control group 25 healthy subjects, were included in the study. All patients underwent ophthalmic examination including visual acuity testing, slit-lamp biomicroscopy, tonometry, gonioscopy (Schaffer classification), and dilated ophthalmoscopy, UB.

RESULTS

Mean age was 35.1 ± 16.2 (range, 11-57) and 34.5 ± 15.6 (range, 9-60) for NF1 and control groups respectively (p>0.05). Lisch nodules were present in 16 of 18 eyes (88.8%) in NF1 group. Fundoscopic examination of the control group and 15 eyes of NF1 (83.3%) patients was normal, whereas hypoplastic and tilted optic nerve were present in three eyes, and temporally-located bone-spicule-like lesions was present in one eye of the NF1 group. UB revealed ciliary body cyst in 77.7% (14/18) of the eyes among NF1 group, and 8% (4/50) among control group (p<0.05). The mean size of the cysts were 520 ± 191 μ (range, 220-860 μ) and 495 ± 231 μ (range, 300-830 μ) at NF1 and control groups, respectively. Gonioscopic evaluation revealed that 55% of the NF1 patients have an unoccludable anterior chamber angle (Grade 3 or 4), 45% occludable angle (Grade 1 or 2), and 78% irregular pigment patches. However, occludable angle rate was just 4% in the control group, and none of the patients had irregular pigment patches.

CONCLUSION

The coexistence of ciliary body cysts and NF1, and the effect of these cysts in the eye should be enlightened with further studies.

Intraocular pressure change in orbital disease

Intraocular pressure change has been found concurrent with many orbital pathologies, particularly those involving proptosis. The objective of this review is to offer an inclusive classification of orbital disease-related intraocular pressure change, not only for oculoplastics and glaucoma specialists, but also for general ophthalmologists. Various orbital conditions associated with increased intraocular pressure and glaucoma are comprehensively summarized, and pathophysiology, clinical manifestations, and treatment options of these diseases are discussed. Graves disease, arterio-venous shunts, trauma, and orbital neoplasia, and other common conditions are discussed in detail; less frequent syndromes such as orbitocraniofacial deformities, phakomatoses, and mucopolysaccharidoses are included for the sake of comprehensiveness, but discussed less extensively.

Study comparing two types of screening provision for people with von Hippel-Lindau disease

Patients diagnosed with von Hippel-Lindau disease (vHL) require life-long surveillance for this multi-system disease. It is therefore important to assess the comprehensiveness of screening provision, as well as identify what type of screening service is most likely to encourage regular patient attendance. This descriptive study reports on two types of screening service: single appointment One Stop (OS) clinics and multiple appointment Ad Hoc (AH) clinics. One hundred and seventeen vHL patients from eight regional genetics centres were approached to take part. Seventy-two (61.5%) returning a completed study questionnaire: fifty-four (75%) were screened at OS clinics and eighteen (25%) at AH clinics. Comprehensiveness of screening, attendance rates, patient ratings of quality of care and levels of psychological morbidity were compared between the two types of service. While levels of disease severity were similar in patients screened at OS and AH clinics, those seen at OS clinics were screened for twice as many site-specific vHL manifestations compared to those seen at AH clinics (P < 0.0001). More patients at OS clinics regularly attended their screening appointments compared to those at AH clinics (P = 0.0045). There was no difference in the quality of care reported by patients attending the two types of screening service and few problems were reported. Twenty-nine percent of respondents were categorised as clinically anxious and 13% as clinically depressed. These findings suggest that an optimum vHL screening service is one based on OS clinics offering regular comprehensive surveillance and psychological support.