Pancreatic neuroendocrine tumors in French VHL mutation carriers: a multicentric retrospective study

BACKGROUND

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

METHODS

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

RESULTS

We included 121 patients with 259 PanNETs. Median age at diagnosis was 38 years. Median follow-up was 89.5 months. PanNET surgical resection was performed in 51 patients. Overall, 29 patients (24%) had metastases (5 synchronous, 10 metachronous), with a higher risk in case of larger PanNET size (p=0.0089; best threshold 28 mm) and grade 2 PanNET (p=0.048), and a pejorative prognostic impact (p=0.043). Patients with PV in VHL exon 1 had larger PanNETs (p=0.018), more often metastatic disease (48% vs 11.5%; p < 0.001) and a trend toward shorter OS (p=0.16).

CONCLUSION

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

Case Report of a Hemangioblastoma Originating from the T1 Spinal Nerve Treated with in Toto Resection, Hemicorporectomy and Pedicle Screw Stabilization

Introduction

Previously, only 40 cases with extradural hemangioblastoma at the spinal nerve (none at the T1 nerve root) have been described in the medical literature. In toto, resection of this hypervascular tumor is essential to avoid bleeding complications. Surgery for hemangioblastoma at the cervicothoracic junction is complex and nerve resection of the T1 results in specific neurodeficits of the hand muscles which are not well known.

Case Report

A 34-year-old woman was diagnosed with a slowly growing tumor located at the left foramen T1/T2. Pressure from the tumor resulted in Horner's syndrome and pain and paresthesia in the upper extremity. The tumor was resected in toto through a posterior midline approach and rib resection and transection of the left T1 and T2 spinal nerves. T2 hemicorporectomy and spinal stabilization were performed to gain access to and mobilize the tumor ventrally. Ptosis decreased after surgery and no neurodeficit was observed except the expected deficit (no deficit was present preoperatively) caused by the T1 resection specifically a small decrease in strength of the abductor and flexor pollicis brevis and opponens pollicis and the lateral two lumbricals. Histological examination of the tumor demonstrated a hemangioblastoma. von Hippel-Lindau disease was ruled out by genetic testing of the patient's blood. Eight-month postoperatively, all pre-operative symptoms had decreased considerably and the radiographic examination shoved unchanged pedicle screw/rod stabilization of the cervicothoracic junction.

Conclusion

Hemangioblastoma is a rare hypervascular tumor very rarely located at the spinal nerve. The tumor should be resected in toto to avoid recurrence and bleeding. In the current case, the location was at the T1 root necessitating complex surgery with laminectomies and hemicorporectomy of T2 and a posterior rib resection/thoracotomy. Spinal stabilization is mandatory. Preferably embolization should be performed preoperatively. T1 transection results in a specific neurodeficit which should be explained to the patient preoperatively. The patients should undergo genetic testing for Hippel-Lindau disease.

Time course of tumorigenesis of a newly developed sporadic hemangioblastoma in an elderly patient: illustrative case

BACKGROUND

von Hippel-Lindau disease-associated hemangioblastomas (HBs) account for 20%-30% of all HB cases, with the appearance of new lesions often observed in the natural course of the disease. By comparison, the development of new lesions is rare in patients with sporadic HB.

OBSERVATIONS

A 65-year-old man underwent clipping for an unruptured aneurysm of the anterior communicating artery. Fourteen years later, follow-up magnetic resonance imaging (MRI) revealed a strongly enhanced mass in the right cerebellar hemisphere, diagnosed as a sporadic HB. A retrospective review of MRI studies obtained over the follow-up period revealed the gradual development of peritumoral edema and vascularization before mass formation.

LESSONS

Newly appearing high-intensity T2 lesions in the cerebellum may represent a preliminary stage of tumorigenesis. Careful monitoring of these patients would be indicated, which could provide options for early treatment to improve patient outcomes.

von-Hippel Lindau and Hypoxia-Inducible Factor at the Center of Renal Cell Carcinoma Biology

The most common form of kidney cancer is clear cell renal cell carcinoma (ccRCC). Biallelic VHL tumor suppressor gene inactivation is the usual initiating event in both hereditary (VHL Disease) and sporadic ccRCCs. The VHL protein, pVHL, earmarks the alpha subunits of the HIF transcription factor for destruction in an oxygen-dependent manner. Deregulation of HIF2 drives ccRCC pathogenesis. Drugs inhibiting the HIF2-responsive growth factor VEGF are now mainstays of ccRCC treatment. A first-in-class allosteric HIF2 inhibitor was recently approved for treating VHL Disease-associated neoplasms and appears active against sporadic ccRCC in early clinical trials.

Total pancreatoduodenectomy for multiple pancreatic cysts in von Hippel-Lindau disease presenting as obstructive jaundice: A case report

INTRODUCTION

Von Hippel-Lindau (VHL) disease can be known as a rare autosomal dominant syndrome that affects some organ systems and is characterized by the growth of both benign and malignant tumors. Diagnosis and management of VHL were needed to have better outcomes.

CASE PRESENTATION

A 39-year-old male with a history of VHL disease and positive family history presented with jaundice and pruritus. He had a history of craniotomy thrice. Laboratory workup revealed elevated total bilirubin level with conjugated bilirubin predominant. The contrast-enhanced MRI showed dilatation of biliary tree with suspicion of partial obstruction by multiple cysts in the pancreas, with ±0.5-5 cm in diameter. A PET/CT scan showed multiple lesions corresponding to VHL disease. The patient underwent total pancreatoduodenectomy. The histopathology finding was multicystic pancreatic hamartoma with neuroendocrine cell hyperplasia.

CLINICAL DISCUSSION

Multiple pancreatic cysts without prior pancreatic inflammatory episodes should suggest VHL disease and prompt a genetic test, according to clinical presentation. As soon as the diagnosis is made, all potential family members must be screened, and those who are affected must receive genetic counseling and strict follow-up care to treat the disease's potentially fatal CNS and visceral manifestations. Total pancreatoduodenectomy was performed according to jaundice, risk of pancreas malignancy, and the existence of endocrine pancreatic insufficiency.

CONCLUSION

Total pancreatoduodenectomy could be performed to relieve the symptom severity and avoid the possibility of malignant changes in VHL.

Inter- and intra-tumor heterogeneity of genetic and immune profiles in inherited renal cell carcinoma

Patients with von Hippel-Lindau disease (vHL) are at risk of developing spatially and temporally multiple clear cell renal cell carcinomas (ccRCCs), which offers a valuable opportunity to analyze inter- and intra-tumor heterogeneity of genetic and immune profiles within the same patient. Here, we perform whole-exome and RNA sequencing, digital gene expression, and immunohistochemical analyses for 81 samples from 51 ccRCCs of 10 patients with vHL. Inherited ccRCCs are clonally independent and have less genomic alterations than sporadic ccRCCs. Hierarchical clustering of transcriptome profiles shows two clusters with distinct immune signatures: immune hot and cold clusters. Interestingly, not only samples from the same tumors but also different tumors from the same patients tend to show a similar immune signature, whereas samples from different patients frequently exhibit different signatures. Our findings reveal the genetic and immune landscape of inherited ccRCCs, demonstrating the relevance of host factors in shaping anti-tumor immunity.

Novel Manifestation of Retinal Hemangioblastomas Detected by OCT Angiography in von Hippel-Lindau Disease

PURPOSE

To elucidate the clinical characteristics of atypical retinal vascular proliferation in patients with von Hippel-Lindau (VHL) disease using OCT angiography (OCTA).

DESIGN

Prospective, observational study.

PARTICIPANTS

Fifty-seven consecutive patients with a diagnosis of VHL disease who visited Kyoto University Hospital between January 2019 and March 2022.

METHODS

Retinal hemangioblastomas (RHs) were assessed using multimodal imaging including OCTA. RHs were classified into 2 phenotypes: nodular and flat. Nodular RHs were defined as typical RHs that were globular, well-circumscribed tumors, often accompanied with dilated feeder arterioles and draining venules. Flat RHs lacked a protruded red or colored mass, had variable and indistinct borders, and were not accompanied with feeder and draining vessels.

MAIN OUTCOME MEASURES

The prevalence, distribution, and description of atypical flat RHs.

RESULTS

Among 57 consecutive patients with VHL disease, 37 patients (64.9%) showed RHs in at least 1 eye. Bilateral RHs were seen in 23 patients (62.2%). Among 58 eyes of 37 patients with RHs, typical nodular RHs were detected in 54 eyes. Nodular RHs were seen mainly in the peripheral retina and occasionally in the peripapillary region, and they showed exudative changes in some cases. Flat RHs were detected in 7 eyes (12.1%). Four eyes showed only flat RHs, and 3 eyes showed both types in the same eye. Most flat RHs appeared as retinal hemorrhages or faint flat abnormal retinal vessels in the inner retina on the fundus examination, often within the macula area or peripapillary. In all eyes with flat RHs, OCTA showed abundant blood flow in the lesions. OCT revealed that flat RHs were seen mainly between the retinal nerve fiber layer and the ganglion cell layer, and occasionally within the inner nuclear layer. During a mean follow-up period of 20.4 ± 15.0 months, no flat RHs accompanied exudative change, tractional retinal detachment, or progression in size.

CONCLUSIONS

Patients with VHL disease can demonstrate 2 distinct types of RHs: the classic nodular type and an atypical flat type. OCT angiography can be useful in improving the detection of atypical flat RHs, which can be difficult to detect clinically.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Comprehensive characterization and building of National Registry of von Hippel-Lindau disease in Brazil

BACKGROUND

Von Hippel-Lindau (VHL) disease is an autosomal dominant disorder caused by pathogenic variants in VHL gene. The common manifestations include hemangioblastomas (HB) of the central nervous system (CNS) and retina (RH); pheochromocytoma (PHEO); clear cell renal cell carcinoma (ccRCC); pancreatic and renal cysts (PRC) and pancreatic neuroendocrine neoplasm (PNEN).

METHODS

The first characterization of VHL in Brazil was published in 2003 and included 20 families with a history of VHL. The aim of this study was to expand the previous Brazilian cohort to include more families, as well as to collect prospectively both clinical and molecular characteristics of patients with VHL to build the VHL Brazilian Registry (VHLBR). Patients with VHL were selected through review of data from medical records of experts and from social networks of support for families with VHL in Brazil.

RESULTS

A total of 142 subjects representing 62 unrelated Brazilian families with VHL were registered. The mean age of VHL onset was 28.78 years old and 128 individuals (90.1%) had at least one VHL-related lesion. CNS HB was the most common manifestation occurring in 91 (71%) patients, followed by multiple PRC (48.4%), RH (39.8%), ccRCC (28.9%), PHEO (12.5%) and PNEN (7.8%). Of the 97 subjects whose presence of VHL variants was confirmed, 51 (52.6%) had missense variants, 22 (22.7%) large deletions, 10 (10.3%) frameshift, 7 (7.2%) splice site, 4 (4.1%) nonsense and 3 (3.1%) in-frame deletions. Regarding surveillance, 115 (81%) participants had at least one physician responsible for their outpatient follow-up; however, 69 (60%) of them did not report a regular frequency of tests.

CONCLUSION

We built the largest prospective VHLBR with organized collections of clinical and genetic data from families with VHL, which will be helpful to guide policies for VHL care and oncogenetics in Brazil. Although there have been improvements in diagnosis and clinical screening methods, VHL care in Brazil is still deficient, especially regarding surveillance and regular medical appointments with experts.

Endolymphatic sac tumour - a rare complication associated with von Hippel-Lindau disease

We report the case of a 42-year - old female with familiar form von Hippel-Lindau disease (VHL) and recurrent endolymphatic sac tumour (ELST), which was presented like non-homogenous, solid and cystic expansion of the left petrous temporal bone. Histologically, there was found lamellae of bone with adjacent ligament and with papillary projections with fibrovascular core. The papillae were lined by a single layer of cuboidal epithelium with hyperchromatic and lightly pleomorphic nuclei. Sporadically, small cystic formations with eosinophilic, PAS positive secretion were noted. Imunohistochemically, the cuboidal cells showed diffuse positivity for vimentin, epithelial membrane antigen (EMA), cytokeratin AE1/AE3 and S100 protein (weakly). Other markers examined, including TTF1, PAX8 and CD10, were negative. Endolymphatic sac tumour is rare low-grade malignant epithelial tumour arising from the endolymphatic sac in the temporal bone, which occurs in 1 out of 30 000 births, with just fewer than 300 cases reported in the literature. About one third of cases are associated with von Hippel- Lindau disease, an autosomal dominant familial cancer syndrome.

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

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

Von Hippel-Lindau disease with intracranial hemorrhage due to arteriovenous anastomosis via multiple spinal hemangioblastomas: illustrative case

BACKGROUND

Some spinal hemangioblastomas (HBLs) resemble spinal vascular malformations. Intracranial subarachnoid hemorrhage (SAH) secondary to spinal HBL has rarely been reported.

OBSERVATIONS

A 67-year-old man with a prolonged von Hippel-Lindau disease (VHL) history presented with sudden headache and vomiting. Cranial and cervical computed tomography (CT) revealed severe infratentorial, supratentorial, and cervical SAH. Cranial CT angiography and magnetic resonance imaging revealed a mismatch in hemorrhage and intracranial tumor localization, with no vascular lesions that could lead to intracranial SAH. Cervical CT angiography revealed abnormal blood vessels originating from 5 spinal tumors suspected to be HBLs. We considered that the SAH was caused by venous reflex from vascular malformation-like spinal HBLs. Transarterial embolization (TAE) of the feeding artery of HBLs was performed to improve symptoms and reduce rebleeding risk. Nine months after TAE, angiography showed no venous reflux into the intracranial space. Ten months later, the authors excised the T1-2 tumor because the patient complained of progressive paralysis of the right upper extremity.

LESSONS

In HBL with prolonged VHL, intracranial hemorrhage due to venous regurgitation via a mimicked vascular malformation may occur. Reducing venous reflux with TAE may improve symptoms and prevent rebleeding.

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.

Synchronous or metachronous presentation of pancreatic neuroendocrine tumor versus secondary lesion to pancreas in patients affected by renal cell carcinoma. Systematic review

The simultaneous or metachronous occurrence of pancreatic neuroendocrine tumor (panNET) and renal cell carcinoma (RCC) may represent a rare coincidence or a manifestation of von Hippel-Lindau disease (VHL). These two malignancies share both radiological and cytopathological features, making the differential diagnosis very challenging. In this review, we collected all cases of concurrent diagnosis of localized panNET and RCC, with or without VHL, as reported in the literature to date. We aimed to provide an insight into the differential diagnosis between panNET and RCC pancreatic metastasis with a focus on the optimal therapeutic algorithm depending on the diagnosis. We performed literature research in PubMed library databases for articles about coexisting panNET and RCC published from 2001 to 2018. We selected nine articles with a total of 13 patients, including one treated at our institution. Patients' median age was 49 years and eight out of 13 patients were women. VHL was diagnosed in nine cases. Most patients underwent radical nephrectomy for RCC (9/13) and a clear cell renal carcinoma variant was identified in six cases. The diagnosis of panNET was synchronous with RCC detection in nine cases and metachronous in four cases. The diameter of the pancreatic lesion was >2 cm in six cases. In two cases the panNET was misdiagnosed as metastatic RCC by radiological tests. Somatostatin receptor scanning was performed only in our patient (Octreoscan) showing intense uptake in the pancreatic mass. Endoscopic ultrasound fine needle aspiration of the pancreatic lesion was performed in four patients: in two cases the panNET was confused with metastatic RCC by cytological analysis. Most patients underwent pancreatic surgery (10/13) without histological confirmation. Clear cell panNET was recognized in six cases, while mixed neuroendocrine non-neuroendocrine neoplasm was diagnosed in one patient. Immunohistochemistry (IHC) staining showed positivity to typical neuroendocrine markers (chromogranin A and synaptophysin) in all reported tested cases (8/8). Three patients underwent systemic treatment: two patients received sunitinib and one patient interleukin-2 (IL-2). Other neoplasms were observed in seven patients, of whom six were affected by VHL syndrome. When neoplastic lesions are recognized in both the kidney and pancreas, panNET and RCC pancreatic metastasis are often misdiagnosed due to similar radiological and cytopathological features. An accurate differential diagnosis is crucial and IHC plays a central role in distinguishing the two entities. The therapeutic algorithm may change depending on the diagnosis: while pancreatic RCC metastases benefit from resection, in panNETs and VHL the indication for surgery must be carefully evaluated.

Characterization of Microscopic Multicellular Foci in Grossly Normal Renal Parenchyma of Von Hippel-Lindau Kidney

Background and Objectives: This study aims to describe the earliest renal lesions in patients with von Hippel-Lindau (VHL) disease, especially the multicellular microscopic pathologic events, to get information into the genesis of renal neoplasms in this condition. Materials and Methods: Multicellular events were identified, and 3dimensional reconstruction was performed in grossly normal kidney parenchyma from VHL disease patients by using H&E-stained slides previously prepared. Results: The lesions were measured and the volume of clusters was calculated. Immunohistochemistry was performed for downstream HIF-target protein carbonic anhydrase 9 (CAIX) as well as CD34 for assessment of angiogenesis. We divided lesions into four types according to lesion height/size. The number of lesions was markedly decreased from lesion 1 (smallest) to lesion 2, then from lesions 2 to 3, and again from lesion 3 to 4. Distribution was highly consistent in the four cases, and the same decrement pattern was seen in all blocks studied. The volumes of clusters were measured and divided into three categories according to their volume. The most frequent pathologic event in VHL kidneys was category 1 (smallest volume), then category 2, and then category 3. Conclusion: We demonstrate that tracking histologic and morphologic changes in 3 dimensions of multicellular microscopic pathologic events enabled us to confirm a protracted sequence of events from smaller to larger cellular amplification events in VHL kidney.

Chronological Progression and Management of Syringobulbia Caused by Spinal Hemangioblastoma: A Case Series and Review of the Literature

BACKGROUND

Syringomyelia often accompanies spinal hemangioblastoma (SHB). It often shows progression to the medulla oblongata, dubbed as "syringobulbia", which presents critical symptoms such as dysphagia and respiratory compromise. Appropriate management of chronological syringomyelia progression toward syringobulbia is not set in stone. This study aims to unravel the clinical and chronological behavior of syringobulbia and its management.

METHODS

A single-institution case series study of 5 patients operated for SHB with syringobulbia was conducted. Serial preoperative magnetic resonance imaging scans were analyzed in further details, especially focusing on the chronological progression of syringomyelia. A literature review was performed to describe clinical/imaging characteristics.

RESULTS

Chronological imaging analyses revealed that despite the relatively steady progression of syringomyelia over years, it accelerated when developing syringobulbia. Intramedullary signal change ("presyringomyelia") was observed in the area where syringomyelia subsequently occurred. Literature review yielded another 15 cases of SHB with syringobulbia, totaling 20 cases. Bulbar dysfunction was seen in 4 cases (20%). Gross total resection was performed in all cases except 1, which underwent just syringotomy. Rapid postoperative symptom improvement was observed in all cases, as well as immediate imaging resolution of syringomyelia.

CONCLUSIONS

The symptoms associated with syringobulbia often become life-threatening. Notably, its resolution may be near-synchronous to surgical resection of the spinal lesion. The speed of progression of syringomyelia is usually steady, but it may accelerate when extending to syringobulbia. Regular imaging follow-up is thus highly recommended to determine the best timing of intervention when presyringomyelia and syringomyelia are ascending toward the medulla oblongata.

Double peeling and endolaser ablation for retinal detachment in von Hippel-Lindau disease

Purpose

To describe a successful surgical approach to macula-off retinal detachment in von Hippel-Lindau disease.

Observations

A 28-year-old male with a history of von Hippel-Lindau disease presented to us with significant worsening of vision in his single functional eye after undergoing a cryotherapy and laser session for multiple retinal capillary hemangioblastomas. Given a tractional and exudative retinal detachment involving macula, we performed a vitrectomy, epiretinal membrane peeling, internal limiting membrane peeling, endophotocoagulation of all hemangioblastomas, and fluid-air exchange. Over 30 days, there was total resolution of retinal detachment and improvement of his vision. At 13-month follow-up, the patient exhibited anatomical and functional stability.

Conclusions and Importance

Double peeling and endolaser ablation may be an alternative treatment approach for patients with tractional and exudative retinal detachment in von-Hippel-Lindau disease.

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

von Hippel Lindau disease (vHL) is caused by a hereditary predisposition to multiple neoplasms, especially hemangioblastomas in the retina and CNS, renal cell carcinomas (RCC), pheochromocytomas, neuroendocrine pancreatic tumours (PNET) and endolymphatic sac tumours. Evidence based approaches are needed to ensure an optimal clinical care, while minimizing the burden for the patients and their families. This guideline is based on evidence from the international vHL literature and extensive research of geno- and phenotypic characteristics, disease progression and surveillance effect in the national Danish vHL cohort. We included the views and preferences of the Danish vHL patients, ensured consensus among Danish experts and compared with international recommendations. RECOMMENDATIONS: vHL can be diagnosed on clinical criteria, only; however, in most cases the diagnosis can be supported by identification of a pathogenic or likely pathogenic variant in VHL. Surveillance should be initiated in childhood in persons with, or at risk of, vHL, and include regular examination of the retina, CNS, inner ear, kidneys, neuroendocrine glands, and pancreas. Treatment of vHL manifestations should be planned to optimize the chance of cure, without unnecessary sequelae. Most manifestations are currently treated by surgery. However, belzutifan, that targets HIF-2α was recently approved by the U.S. Food and Drug Administration (FDA) for adult patients with vHL-associated RCC, CNS hemangioblastomas, or PNETs, not requiring immediate surgery. Diagnostics, surveillance, and treatment of vHL can be undertaken successfully by experts collaborating in multidisciplinary teams. Systematic registration, collaboration with patient organisations, and research are fundamental for the continuous improvement of clinical care and optimization of outcome with minimal patient inconvenience.

Imaging manifestations of von Hippel-Lindau disease: an illustrated guide focusing on the central nervous system

Von Hippel-Lindau (VHL) disease is a rare, autosomal dominant inherited syndrome that affects the germline of the VHL gene, a tumor suppressor gene. VHL disease is characterized by the multisystemic development of a variety of benign and malignant tumors, especially in the central nervous system (CNS). Such tumors include retinal and CNS hemangioblastomas, as well as endolymphatic sac tumors. The various tumor sites are responsible for the diversity of signs and symptoms related to the disease. The mean age at symptom onset is 33 years. Despite medical advances, the average life expectancy of patients with VHL disease is 49 years. Imaging plays a pivotal role in the clinical diagnosis and is essential to the follow-up of patients with VHL disease. This pictorial essay describes characteristic CNS manifestations of VHL disease-related tumors that all radiology residents should be aware of.

Retinal Capillary Hemangioma Leading to a Diagnosis of von Hippel-Lindau Disease in a Patient with Retinopathy of Prematurity

Von Hippel-Lindau (VHL) disease is a rare inherited cancer syndrome that results in the development of tumor formation in multiple systems. In the eye, retinal capillary hemangioma (RCH) can lead to severe vision loss. Retinopathy of prematurity (ROP) is likewise a rare disease in which abnormal retinal vasculature develops in premature infants. Hallmarks of this disease include temporal dragging of the macula and retinal vessels. Here, we describe a 36-year-old myopic woman with a known history of ROP who presented with a vitreous hemorrhage in the right eye. As the vitreous hemorrhage cleared, she was found to have not only a retinal tear but also a juxtapapillary RCH that lead to a diagnosis of VHL disease in the patient, her mother, and her aunt. This is the first reported case of an individual with concomitant ROP and RCH from VHL. Her vision was remarkably well preserved over 25 years of follow-up despite having a moderate-sized laser scar temporal to the disc from treating the juxtapapillary RCH, likely due to the temporal macular dragging from her underlying ROP. This case highlights the importance of being aware that rare diagnoses can co-exist, and one must be aware of the protean manifestations of VHL.

The Pathologic and Molecular Genetic Landscape of the Hereditary Renal Cancer Predisposition Syndromes

It is estimated that 5-8% of renal tumors are hereditary in nature with many inherited as autosomal dominant. These tumors carry a unique spectrum of pathologic and molecular alterations, the knowledge of which is expanding in the recent years. Indebted to this knowledge, many advances in treatment of these tumors have been achieved. In this review, we summarize the current understanding of the genetic renal neoplasia syndromes, the clinical and pathologic presentations, their molecular pathogenesis, the advances in therapeutic implications and targeted therapy.

Adrenal hemangioblastoma

Hemangioblastoma (HB) is a rare benign tumor that most commonly occurs in the cerebellum. HB is composed of neoplastic stromal cells and abundant small vessels. However, the exact origin of stromal cells is controversial. Extraneural HBs have been reported in a small series, and peripheral HBs arising in the adrenal gland are extremely rare. Herein, we report a case of sporadic adrenal HB in a 54-year-old woman. The tumor was a well-circumscribed, yellow mass measuring 4.2 cm in diameter. Histologically, the tumor was composed of small blood vessels and vacuolated stromal cells with clear cytoplasm. On immunohistochemical stain, the stromal cells were positive for S-100 protein, neuron-specific enolase, and synaptophysin. The tumor did not reveal mutation of VHL alleles. We herein present a case of HB of the adrenal gland and review of the literature.

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.

The latest developments in the area of therapeutic delivery excluding some diseases, such as COVID-19 and the big three (HIV/AID, malaria and tuberculosis)

It is the beginning of a new decade, where COVID-19 and the 'big three' (HIV/AID, malaria and tuberculosis) have raised public awareness of the type of challenges researchers face every day. Beyond these diseases, there are also still many more for which scientists are working to develop new therapies and their impact in healthcare is enormous too. This industry update covers the period 1-31 August 2021, and some examples of research and approvals for many other diseases excluding COVID-19 and the 'big three' are presented. There is a progressive trend of approvals of novel drug candidates and the proposal of new indications for the existing ones. Some patents related to rare diseases were also published during this month. Information and analyses were sourced from scientific literature, regulatory and patent agencies, websites and press releases of the companies (and not based upon personal opinion). The main reason of leaving COVID-19 research outside the scope of this update is mainly due to the rapid growth and change in this field; some preliminary results require further research and scientists must be aware of the final impact that this research could have on public opinion. Moreover, as a result of disruptions to health care in the face of COVID-19, several research groups simply stopped their research in other diseases and, for that reason, it is imperative to sum up some important advances in other critical diseases and health areas.

Involvement of PBRM1 in VHL disease-associated clear cell renal cell carcinoma and its putative relationship with the HIF pathway

Von Hippel-Lindau (VHL) disease is the main cause of inherited clear-cell renal cell carcinoma (ccRCC) and is caused by germline mutations in the VHL tumor suppressor gene. Bi-allelic VHL alterations lead to inactivation of pVHL, which plays a major role by downstream activation of the hypoxia inducible factor (HIF) pathway. Somatic VHL mutations occur in 80% of sporadic ccRCC cases and the second most frequently mutated gene is polybromo 1 (PBRM1). As there is currently no data regarding PBRM1 involvement in VHL disease-associated ccRCC, the aim of the present study was to assess the PBRM1 mutational status, and PBRM1 and HIF expression in VHL disease-associated ccRCC series compared with a sporadic series. PBRM1 gene was screened by Sanger sequencing for 23 VHL-disease-associated ccRCC and 22 sporadic ccRCC cases. Immunohistochemical studies were performed to detect the expression of PBRM1, HIF1 and HIF2 for all cases. In VHL-associated tumors, 13.0% (n=3/23) had PBRM1 somatic mutations and 17.4% (n=4/23) had a loss of PBRM1 nuclear expression. In sporadic cases, 27.3% (n=6/22) showed PBRM1 somatic mutations and 45.5% (n=10/22) had a loss of PBRM1 nuclear expression. Loss of PBRM1 was associated with an advanced tumor stage. HIF1-positive tumors were observed more frequently in the VHL-associated ccRCC than in the sporadic series. Furthermore, in the VHL cohort, PBRM1 expression appeared to be associated more with HIF1 than with HIF2. Given that hereditary tumors tend to be less aggressive, these results would suggest that co-expression of PBRM1 and HIF1 may have a less oncogenic role in VHL-associated ccRCC.

Molecular characterisation of sporadic endolymphatic sac tumours and comparison to von Hippel-Lindau disease-related tumours

AIMS

Although inactivation of the von Hippel-Lindau gene (VHL) on chromosome 3p25 is considered to be the major cause of hereditary endolymphatic sac tumours (ELSTs), the genetic background of sporadic ELST is largely unknown. The aim of this study was to determine the prevalence of VHL mutations in sporadic ELSTs and compare their characteristics to VHL-disease-related tumours.

METHODS

Genetic and epigenetic alterations were compared between 11 sporadic and 11 VHL-disease-related ELSTs by targeted sequencing and DNA methylation analysis.

RESULTS

VHL mutations and small deletions detected by targeted deep sequencing were identified in 9/11 sporadic ELSTs (82%). No other cancer-related genetic pathway was altered except for TERT promoter mutations in two sporadic ELST and one VHL-disease-related ELST (15%). Loss of heterozygosity of chromosome 3 was found in 6/10 (60%) VHL-disease-related and 10/11 (91%) sporadic ELSTs resulting in biallelic VHL inactivation in 8/10 (73%) sporadic ELSTs. DNA methylation profiling did not reveal differences between sporadic and VHL-disease-related ELSTs but reliably distinguished ELST from morphological mimics of the cerebellopontine angle. VHL patients were significantly younger at disease onset compared to sporadic ELSTs (29 vs. 52 years, p < 0.0001, Fisher's exact test). VHL-disease status was not associated with an increased risk of recurrence, but the presence of clear cells was found to be associated with shorter progression-free survival (p = 0.0002, log-rank test).

CONCLUSION

Biallelic inactivation of VHL is the main mechanism underlying ELSTs, but unknown mechanisms beyond VHL may rarely be involved in the pathogenesis of sporadic ELSTs.

Intravitreous treatment of severe ocular von Hippel-Lindau disease using a combination of the VEGF inhibitor, ranibizumab and PDGF inhibitor, E10030: Results from a phase 1/2 clinical trial

BACKGROUND

Treatment options for severe ocular von Hippel-Lindau (VHL) disease are limited. This trial evaluated preliminary safety and potential efficacy of combination intravitreous injection with ranibizumab, a vascular endothelial growth factor (VEGF) inhibitor, and E10030, a PDGF inhibitor, for eyes with VHL disease-associated retinal hemangioblastoma (RH) not amenable or responsive to thermal laser photocoagulation.

METHODS

This was a prospective, single-arm, open-label phase 1/2 study, comprised of three adults with VHL-associated RH and vision loss. Intravitreous injections of ranibizumab (0.5 mg) and E10030 (1.5 mg) were given unilaterally every 4 weeks in the study eye through 16 weeks, then every 8 weeks through 48 weeks. Supplementary standard care therapies were allowed without restriction after 40 weeks. The primary outcome was the ocular and systemic adverse effect profile at 52 weeks. Secondary outcomes included changes in best-corrected visual acuity (BCVA), RH size, exudation, epiretinal proliferation and retinal traction, and need for ablative treatment of RH or ocular surgery at week 52.

RESULTS

Three participants each received nine injections prior to week 52 and were followed for 104 weeks. One participant manifested mild episodic ocular hypertension in the study eye. Change in BCVA in the study eye at week 52 for the three participants was -5, -12 and +2 letters. No reduction in RH size was measured at 52 weeks. Variable mild improvements in exudation in two participants at week 16 were not sustained through week 52.

CONCLUSIONS

Combination intravitreous injection with ranibizumab and E10030 demonstrated a reasonable preliminary safety profile, but limited treatment effect.

Reoperative Partial Nephrectomy-Does Previous Surgical Footprint Impact Outcomes?

PURPOSE

Historically, open techniques have been favored over minimally invasive approaches for complex surgeries. We aimed to identify differences in perioperative outcomes, surgical footprints, and complication rates in patients undergoing either open or robotic reoperative partial nephrectomy.

MATERIALS AND METHODS

A retrospective review of patients undergoing reoperative partial nephrectomy was performed. Patients were assigned to cohorts based on current and prior surgical approaches: open after open, open after minimally invasive surgery, robotic after open, and robotic after minimally invasive surgery cohorts. Perioperative outcomes were compared among cohorts. Factors contributing to complications were assessed.

RESULTS

A total of 192 patients underwent reoperative partial nephrectomy, including 103 in the open after open, 10 in the open after minimally invasive surgery, 47 in the robotic after open, and 32 in the robotic after minimally invasive surgery cohorts. The overall and major complication (grade ≥3) rates were 65% and 19%, respectively. The number of blood transfusions, overall complications, and major complications were significantly lower in robotic compared to open surgical cohorts. On multivariate analysis, the robotic approach was protective against major complications (OR 0.3, p=0.02) and estimated blood loss was predictive (OR 1.03, p=0.004). Prior surgical approach was not predictive for major complications.

CONCLUSIONS

Reoperative partial nephrectomy is feasible using both open and robotic approaches. While the robotic approach was independently associated with fewer major complications, prior approach was not, implying that prior surgical approaches are less important to perioperative outcomes and in contributing to the overall surgical footprint.

From oxygen sensing to angiogenesis: Targeting the hypoxia signaling pathway in metastatic kidney cancer

PURPOSE

This article summarizes examples of current and emerging therapies that target the hypoxia and angiogenesis signaling pathways in the clear cell type of renal cell cancer (RCC), with an emphasis on the hypoxia signaling pathway.

SUMMARY

Mammalian cells transduce signals of decreased oxygen to hypoxia inducible factor (HIF), an intracellular heterodimer that mediates the adaptation of normal and tumor cells to oxygen deprivation. HIF is frequently overexpressed in cancer cells and is involved in the transcriptional activation of many genes essential for cell invasion, migration, survival, and angiogenesis (including vascular endothelial growth factor [VEGF]). Moreover, HIF confers resistance to cytotoxic chemotherapy and radiation therapy and is associated with poor prognosis in patients with cancer. Blocking the activity of HIF inhibits the expression of VEGF and oncogenic pathways, resulting in the inhibition of tumor growth. Interestingly, activation of oncogenes and/or inactivation of tumor suppressor genes (eg, the gene encoding von Hippel-Lindau [VHL] tumor suppressor protein) can activate tumorigenesis even with normal levels of oxygen, providing support for the notion that the HIF-VHL-VEGF axis is amenable to targeted therapies for the treatment of RCC. This article highlights the current understanding of the hypoxia signaling pathway and its relevance to RCC development. Pharmacologic agents targeting the hypoxia and angiogenesis signaling pathways are discussed.

CONCLUSION

Development of novel therapeutic agents that target the hypoxia and angiogenesis signaling pathways holds promise in the management of metastatic clear cell RCC.

Clinical Results of Various Treatments for Retinal Capillary Hemangioma

PURPOSE

We report the clinical outcomes of retinal capillary hemangioma (RCH) after the application of various treatments.

METHODS

We performed a retrospective chart analysis of eight eyes treated for RCH between August 2009 and January 2018. During the follow-up period, the status and progression of the RCHs were checked by fundus photography, fluorescein angiography, and optical coherence tomography, and additional treatments were applied when necessary.

RESULTS

Three of the five patients had bilateral RCH, and two had unilateral RCH. Six eyes received laser photocoagulation; two eyes received cryotherapy, and one eye received intravitreal Avastin injection. Three eyes each had intravitreal triamcinolone injection, subtenon triamcinolone injection, and intravitreal dexamethasone injection to control inflammation. Also, two patients took oral prednisolone, and one patient used prednisolone eye drops to control inflammation. Two eyes underwent vitrectomy and scleral buckling due to deterioration of the epiretinal membrane and vitreal traction, respectively. As a result of those treatments, the tumors were stable in five of the eight eyes. However, one eye is now in a pre-phthisis state, and one patient who refused treatment showed progression of the tumor, epiretinal membrane, and traction.

CONCLUSIONS

Because RCHs vary in size, the degree of inflammation, and symptoms, this disorder should be actively treated on a case-by-case basis. Fluorescein angiography should be used periodically to determine recurrence of the tumor or inflammation, and the appropriate treatment should be repeated as necessary. Moreover, regular systemic screening tests for von Hippel-Lindau disease should be performed in RCH patients to ensure that they have no abnormalities other than in the eye.

MK-6482 as a potential treatment for von Hippel-Lindau disease-associated clear cell renal cell carcinoma

INTRODUCTION

Von Hippel-Lindau (VHL) disease is an inherited autosomal dominant syndrome caused by a germline mutation and/or deletion of the VHL gene. Inappropriate hypoxia-inducible factor (HIF)-mediated transcription of proangiogenic and metabolic genes leads to the development of tumors and cysts in multiple organs. Surgery is a standard treatment for localized tumors with a risk of metastasis or organ dysfunction. Repeated surgeries cause substantial morbidity and have a major impact on quality of life. There is an urgent need to develop effective and safe systemic treatments for VHL disease manifestations. The small-molecule HIF 2 alpha inhibitor MK-6482 (belzutifan) has demonstrated significant efficacy in VHL disease related renal cell carcinomas, hemangioblastomas, and pancreatic neuroendocrine tumors while demonstrating an acceptable safety profile.

AREAS COVERED

This paper reviews the development of the HIF-2 alpha inhibitor, MK-6482, and discusses preliminary results of ongoing phase I/II studies in renal cell carcinoma (RCC) and VHL disease. An examination of ongoing clinical development of MK-6482 and perspectives on potential future developments and challenges are offered.

EXPERT OPINION

Because of its favorable safety profile, its clear efficacy in VHL disease, promising findings in sporadic, advanced RCC, and convenient oral formulation, MK-6482 is expected to become a leading treatment for VHL disease. Among other currently available oral agents, we believe that MK-6482 will be a preferred treatment for VHL-associated RCC.

Clinical challenges and dilemmas in the management of advanced pancreatic neuroendocrine tumour - the first manifestation of von Hippel-Lindau disease in a young patient

Not required for Clinical Vignette.

Pancreatic neuroendocrine tumours in patients with von Hippel-Lindau disease

Von Hippel-Lindau disease is a highly penetrant autosomal genetic disorder caused by a germline mutation in the tumour suppressor gene, manifesting with the formation of various tumours, including neuroendocrine tumours of the pancreas. The incidence of the latter is not very high, varying from 5% to 18%. To compare, haemangioblastomas and clear cell renal carcinoma are present in 70% of von Hippel-Lindau patients and are considered the main prognostic factors, with renal cancer being the most common cause of death. However, pancreatic neuroendocrine tumours should not be neglected, considering their malignant potential (different to sporadic cases), natural history, and treatment protocol. This paper aims to review the literature on the epidemiology, natural history, treatment, and surveillance of individuals affected by pancreatic neuroendocrine tumours in von Hippel-Lindau disease.

Combined Laparoscopic and CT Monitoring of the Ice-Ball Margin during Cryoablation for Renal Cell Carcinoma Associated with von Hippel-Lindau Disease: First Case

We report a 47-year-old Japanese female with 10 previous treatments for multiple bilateral renal cell carcinoma (RCC) associated with von Hippel-Lindau disease. The 14-mm right lower pole renal tumor was in contact with the right ureter. Laparoscopic cryoablation was performed to protect the ureter wrapped with gauze. Computed tomography (CT) monitoring was used to confirm the precise ≥ 6 mm ice-ball margin. There was no local progression at 6-months post-surgery. The serum creatinine has been stable. This is apparently the first report of combined laparoscopic and CT monitoring of an ice-ball formation and its margin during cryoablation for RCC.

Laser speckle flowgraphy in juxtapapillary retinal capillary hemangioblastoma: a case report on natural course and therapeutic effect

Juxtapapillary retinal capillary hemangioblastoma (JRCH), a benign intraocular vascular tumor, is usually progressive and may lead to severe vision loss due to various complications. We herein present a case of JRCH observed with laser speckle flowgraphy (LSFG) before and after laser photocoagulation (LPC). A 21-year-old Japanese woman underwent LSFG evaluations. Right eye showed an orange-colored tumor consistent with JRCH on the papillomacular bundle, where LSFG showed a mild warm-color blood flow signal. Eight months after the first examination, JRCH in the right eye increased redness with vasodilatation, and the size enlarged, where LSFG showed a stronger warm-color blood flow signal. She underwent direct yellow laser ablation for the JRCH lesion. One week after LPC, JRCH became paler and LSFG eventually depicted a weakened blood flow signal at the same site. In conclusion, non-invasive and reproducible LSFG is a useful tool for assessing not only JRCH activity but also therapeutic effect.

Bilateral pheochromocytoma: Clinical characteristics, treatment and longitudinal follow-up

OBJECTIVE

Comprehensive data about patients with bilateral pheochromocytoma are limited. We aimed to describe the clinical presentation, genetic analysis, treatment and outcomes of patients with bilateral pheochromocytoma.

DESIGN

A retrospective study at a tertiary care centre.

PATIENTS

All patients with bilateral pheochromocytoma evaluated at Mayo Clinic in Rochester, Minnesota between January 1951 and December 2015.

MEASUREMENTS

Tumour size, genetic testing, plasma/urine metanephrines and catecholamines.

RESULTS

A total of 94 patients (51% women) were diagnosed with bilateral pheochromocytoma at a median age at first presentation of 31 years (range, 4-70). Bilateral disease was noted in 8.0% of pheochromocytoma patient overall and 37.5% of patients 18 years of younger. Most patients presented with synchronous tumours (80%). Median time to metachronous tumours was 4.5 years (range, 1-38). Genetic disease was identified in 75 (80%) patients, including MEN 2A (42.6%), VHL (19.1%), MEN 2B (9.6%) and NF1 (8.5%). Excess catecholamines were present in 97% of patients. Patients with synchronous pheochromocytoma commonly underwent simultaneous bilateral adrenalectomy (99%), and 18 (24%) had cortical-sparing surgery. Multicentric tumours were reported in 23 of 77 (30%) patients with available data. Recurrent disease was found in 9.6% of patients, and 8.5% developed metastatic disease. Median follow-up was 8.5 years. At the study conclusion, 4 patients had died due to pheochromocytoma or adrenalectomy.

CONCLUSIONS

Bilateral pheochromocytoma occurred in 7.0% of adults with pheochromocytoma and 37.5% of paediatric patients. Genetic disease was identified in 80% of patients, predominantly MEN2A. Multicentric tumours were common, but most were still cured following adrenalectomy.

Invasive management of renal cell carcinoma in von Hippel-Lindau disease

Introduction

Patients affected by von Hippel-Lindau (VHL) disease experience an increased risk for bilateral, synchronous, and metachronous renal cell carcinoma (RCC). Oncologic and functional outcomes are the main goals in the management of renal masses. We present our protocol for patients with VHL disease-associated RCC alongside functional and oncologic results observed in our series.

Material and methods

We performed a retrospective analysis of our clinical database of patients with VHL disease-associated RCC referred to our department between June 2005 and December 2017. We offer surveillance for lesions <2 cm and active management with radiofrequency ablation (RFA) for lesions 2-3 cm, and nephron-sparing surgery (NSS), RFA or embolization techniques for lesions >3 cm or growth rate >1 cm/year.

Results

Our series comprises 14 patients, of whom 13 had undergone at least one invasive procedure for RCC, mean age at first intervention was 27 years (range 18-60). Overall, 30 interventions were performed in 21 kidneys: four radical nephrectomies, 13 RFAs, 12 NSSs, and one embolization. During follow-up (median time: 41 months, range: 6-149), eight patients (57%) presented with new lesions that required treatment, with a mean time between treatments of 32 ±18.5 months. No metastatic progression or need for dialysis was recorded; the success rate for RFA was 85%.

Conclusions

Management of VHL kidney disease by NSS is the standard of care with a cut-off at 3 cm, ablative procedures should be offered to lesions ranging 2-3 cm in size. Follow-up should be done strictly in referral centers that can provide all treatment options to renal function and control oncologic progression.

Cumulative surgical morbidity in patients with multiple cerebellar and medullary hemangioblastomas

OBJECTIVE

Patients affected with von Hippel-Lindau disease often develop multiple hemangioblastomas in the cerebellum and spinal cord. Timing of surgical intervention is difficult and depends largely on the anticipated surgical morbidity. However, data regarding surgical outcome after multiple cerebellar and medullary surgeries are scarce. Our objective was to evaluate cumulative surgical morbidity in patients operated on multiple cerebellar and medullary hemangioblastomas and to deduce recommendations for treatment.

METHODS

We performed a retrospective analysis for a consecutive cohort of von Hippel-Lindau patients with surgical treatment of at least two cerebellar and/or medullary hemangioblastomas. Pre- and postoperative functional grades were reviewed in patients' files and compared by Modified Ranking Scale (cerebellar surgeries) or by Modified McCormick Score (medullary surgeries).

RESULTS

Thirty-six patients were surgically treated for at least two cerebellar hemangioblastomas (12 patients), at least two medullary hemangioblastomas (19 patients) or at least two hemangioblastomas in both locations (5 patients). Fourthy-eight cerebellar and 80 medullary procedures were performed in total. On average, multiple cerebellar surgeries caused no clinical deterioration, whereas multiple medullary surgeries led to a slight cumulative deterioration of postoperative functional grades. The severity of this deterioration did not correlate to the number of performed medullary surgeries.

CONCLUSION

Resection of multiple cerebellar hemangioblastomas is not associated with cumulative morbidity. Although there is a certain cumulative surgical morbidity caused by medullary surgeries, its extent does not increase with the number of performed surgeries. Microsurgical removal of asymptomatic tumors with radiographic progression can also be considered for patients with multiple tumors and previous surgeries.

Clinical diagnosis, treatment and screening of the VHL gene in three von Hippel-Lindau disease pedigrees

The present study aimed to investigate the clinical characteristics of von Hippel-Lindau (VHL) disease and the clinical significance of VHL gene detection. The clinical materials of patients with VHL disease were collected from 3 different families between May 1985 and October 2017. A systematic pedigree study and VHL gene detection at the germline level were performed together with a literature review. Of the 22 patients from 3 VHL pedigrees, 10 exhibited VHL gene mutations (3 genotypes) at the germline level. The genotypes of pedigree were VHL-p.R161Q (c.482G>A), VHL-p.N78S (c.233A>G), and VHL-p.R167Q (c.500G>A). During the follow-up period, the symptoms were stable in 10 patients, including 2 cases of central nervous system hemangioblastomas (CNS-HB), 3 cases of bilateral multiple renal cell carcinoma (RCC) and 5 cases of adrenal pheochromocytoma without local recurrence or distant metastasis. Patients with p.R161Q and p.N78S were not associated with CNS-HB, which was different from the clinical phenotype of previously reported families. RCC were Fuhrman II grade, which was consistent with the previous study. The results of the present study indicated that the standardization of early diagnosis and the improvement of long-term efficacy may be achieved by combining clinical screening and VHL gene detection.

Comparison of Current Optical Coherence Tomography Angiography Methods in Imaging Retinal Hemangioblastomas

Purpose

To compare spectral-domain (SD) and swept-source (SS) optical coherence tomography angiography (OCTA) for imaging retinal capillary hemangioblastomas (RCHs) in von Hippel-Lindau disease (VHLD).

Methods

Prospective single-center cross-sectional study. Tumor size (TS) of perfused RCHs was assessed clinically in relation to the optic disc size. For both technologies, SD-OCTA and SS-OCTA, corresponding images with a scan size of 3 × 3 mm² and 6 × 6 mm², respectively, were overlaid according to the set of marker positions to determine the TS.

Results

From 200 patients with VHLD, 48 patients showed 84 RCHs. SD-OCTA images of 39 RCHs (46.4%) and SS-OCTA images of 48 RCHs (57.2%) were suitable for analysis. The average in OCTA-measured TS of 1.60 ± 2.58 mm² (range, 0.01–10.43) was congruent to the clinically assessed TS in 81.3% of cases (r = 0.86, P < 0.0001). TS measured in SD-OCTA compared to SS-OCTA showed similar values and a high correlation (all P < 0.0001). Nevertheless, despite the similarities, a slight trend in SS-OCTA was observed whereby with increasing TS, an elevated TS was detected compared to SD-OCTA (3 × 3-mm² scans: mean difference of 0.03 ± 0.04  mm², 6 × 6-mm² scans: 0.08 ± 0.19 mm²). However, within the same imaging technology method, TS values almost did not differ (SD-OCTA: mean difference of 0.01 ± 0.02 mm², SS-OCTA: 0.001 ± 0.01 mm²).

Conclusions

OCTA may serve as an additional tool for diagnosis and monitoring of RCHs. Nevertheless, due to the differences between the technologies, the values cannot be used interchangeably.

Translational Relevance

SD-OCTA and SS-OCTA are suitable to detect and monitor RCHs and provide a more detailed assessment about the TS than this is clinically possible.

Clinical features and treatment of endolymphatic sac tumor

Background: Endolymphatic sac tumor (ELST) is an extremely rare disease that does not have established clinical guidelines.Objective: To provide guidance for the diagnosis and management of ELSTs.Methods: We retrospectively reviewed the medical records of patients who were suspected to have a lesion in the location of endolymphatic sac. Seven patients were included. Histopathologic diagnosis confirmed five ELSTs and two other diseases.Results: All of the enrolled patients had hearing impairment. Facial palsy was found in four out of five patients with ELST, whereas none of the patients in other disease group showed facial palsy. CT and MRI findings were consistent with those in previous literatures; however, angiographic findings were not consistent with those previously reported. All patients underwent surgery. Recurrence occurred in two patients with ELST, although there was no visible remnant tumor after the operation. These patients were treated with stereotactic radiosurgery.Conclusion: Hearing impairment and facial palsy were representative symptoms of ELST. All ELSTs showed 'salt and pepper' signal in MRI T1-weighted images, and smaller tumors could have blood supply from AICA in the radiologic study. Complete surgical resection with optional stereotactic radiosurgery should be considered in ELST.HighlightsHearing impairment and facial weakness are remarkable symptoms of ELST compared to other diseases that invade the endolymphatic sac.All ELSTs showed 'salt and pepper' signal in MRI T1-weighted images.ELST less than 3 cm in diameter could have blood supply from AICA.A complete surgical excision with optional stereotactic radiosurgery is required.

Role of VHL-JAK-STAT signaling pathway in central nervous system hemangioblastoma associated with von Hippel-Lindau disease

INTRODUCTION

Central nervous system hemangioblastoma is a benign tumor associated with or without von Hippel-Lindau (VHL) disease which is an autosomal dominant hereditary disease that results from a germline mutation in the VHL gene. A main axis of signaling pathways in central nervous system hemangioblastoma is VHL-HIF signaling pathway. Here, we propose an alternative VHL-JAK-STAT signaling pathway in hemangioblastoma and discuss the role.

METHODS

Using MACS method, Scl⁺ hemangioblast-like cells were isolated from multipotent nestin-expressing stem cells. Then, ubiquitination of JAK2 in those cells and immunoprecipitation between JAK2 and VHL were examined. Then, expressions of JAK2 and STAT3 in those cells and expressions of VHL-associated hemangioblastoma tissues were examined. In addition, the VHL genes of patients bearing hemangioblastoma were analyzed.

RESULTS

JAK2 and STAT3 in Scl⁺ hemangioblast-like cells were ubiquitinated after VHL- expression vector was transferred to those cells. Expressions of JAK2 and STAT3 in those cells were well recognized before the transfer, but those disappeared after the transfer. Expressions of both JAK2 and STAT3 in hemangioblastoma tissues were well shown. The VHL gene analysis revealed that patients bearing hemangioblastoma carried missense mutations in 5, small deletions in 2, large deletions in 4, and nonsense mutation in 1 CONCLUSIONS: VHL-JAK-STAT signaling pathway might play an important role in proliferation, angiogenesis, and maintenance of stem-cell-nature in hemangioblastoma as an alternative signaling pathway to supplement VHL-HIF signaling pathway.

Case report: a synonymous VHL mutation (c.414A > G, p.Pro138Pro) causes pathogenic familial hemangioblastoma through dysregulated splicing

Background

von Hippel-Lindau (VHL) disease is a familial neoplasia syndrome that results from the germline mutation of VHL. Pathogenic VHL mutations include deletion, frameshift, nonsense and missense mutations. Synonymous mutations are expected to be phenotypically silent and their role in VHL disease remains poorly understood.

Case presentation

We report a Caucasian male with a family history of pheochromocytoma and the synonymous VHL mutation c.414A > G (p.Pro138Pro). At 47-years, MRI revealed pheochromocytoma in the left adrenal gland and hemangioblastomas in the spine and brain. Pheochromocytoma was treated by adrenalectomy. Radiotherapy, followed by craniotomy and resection were needed to reduce hemangioblastomas to residual lesions. Two of three of the proband’s children inherited the mutation and both presented with retinal hemangioblastomas without pheochromocytoma at age 7: one twin needed four laser treatments. Primary skin fibroblasts carrying the heterozygous mutation or wild type VHL were established from the family. Mutant fibroblasts downregulated full-length VHL mRNA and protein, and upregulated the short VHL mRNA isoform (a result of exon 2 skipping in splicing) at the mRNA level but not at the protein level.

Conclusions

Our study shows that the synonymous VHL mutation c.414A > G can within 7 years induce pediatric retinal hemangioblastoma in absence of pheochromocytoma. This highlights the need to include splicing-altering synonymous mutations into the screening for VHL disease. This is also the first report on detecting and validating a synonymous VHL mutation using patient-derived fibroblasts. The mutation c.414A > G translates to p.Pro138Pro, yet it is not functionally silent, because it causes aberrant splicing by skipping exon 2. The reduced but not completely abolished pVHL protein in a loss-of-heterozygosity genetic backdrop may underlie the etiology of VHL disease.

Familial Kidney Cancer: Implications of New Syndromes and Molecular Insights

CONTEXT

Hereditary cases account for about 5% of all cases of renal cell carcinoma (RCC). With advances in next-generation sequencing, several new hereditary syndromes have been described in the last few years.

OBJECTIVE

To review and summarise the recent preclinical and clinical literature in hereditary renal cancer.

EVIDENCE ACQUISITION

A systematic review of the literature was performed in November 2018 using PubMed and OMIM databases, with an emphasis on kidney cancer, genetics and genomics, clinical criteria, and management.

EVIDENCE SYNTHESIS

Several autosomal dominant hereditary RCC syndromes have been described, including those related to germline pathogenic variants in VHL, MET, FH, TSC1/TSC2, FLCN, SDHA/B/C/D, BAP1, CDC73, and MITF. Clinical spectrum of SDH, BAP1, and MITF is still being defined, although these appear to be associated with a lower incidence of RCC. FH and likely BAP1 RCC are associated with more aggressive disease. Preclinical and clinical studies show that using systemic therapy that exploits specific genetic pathways is a promising strategy.

CONCLUSIONS

There are several well-described hereditary RCC syndromes, as well as recently identified ones, for which the full clinical spectrum is yet to be defined. In the new era of precision medicine, identification of these syndromes may play an important role in management and systemic treatment selection.

PATIENT SUMMARY

This review covers updates in the diagnosis and management of familial kidney cancer syndromes. We describe updates in testing and management of the most common syndromes such as von Hippel-Lindau, and hereditary leiomyomatosis and renal cell carcinoma. We also provide insights into recently described familial kidney cancer syndromes.

The Efficacy and Safety of Tyrosine Kinase Inhibitors for Von Hippel-Lindau Disease: A Retrospective Study of 32 Patients

Background: Von Hippel-Lindau (VHL) disease is an autosomal-dominant hereditary cancer syndrome. Currently, studies on tyrosine kinase inhibitor (TKI) therapy for VHL disease are scarce. In this study, we retrospectively evaluated the efficacy and safety of four TKIs in patients with VHL disease. Methods: Patients diagnosed with VHL disease who were receiving TKIs were recruited. Patients were treated with sunitinib (n = 12), sorafenib (n = 11), axitinib (n = 6), or pazopanib (n = 3). The therapeutic response was evaluated according to the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Results: From July 2009 to September 2018, 32 patients with VHL disease were eligible and included in this study. The median duration of TKI therapy was 22 months (IQR 8.5-44.75), and the median follow-up period was 31.5 months (IQR 13.5-63.5). According to the RECIST, 9 (28%) of 32 patients showed a partial response, 15 (47%) achieved stable disease, and eight exhibited continued disease progression. A partial response was observed in 11 (31%) of 36 renal cell carcinomas, 4 (27%) of 15 pancreatic lesions, and 1 (20%) of five central nervous system (CNS) hemangioblastomas. The average tumor size decreased significantly for renal cell carcinomas (P = 0.0001), renal cysts (P = 0.027), and pancreatic lesions (P = 0.003) after TKI therapy. Common side effects included hand-foot skin reactions, diarrhea, alopecia, thrombocytopenia, and fatigue. Conclusions: Partial alleviation of VHL disease-related tumors can be achieved by TKI therapies in some patients, providing an alternative treatment strategy, and the side effects of TKIs are acceptable. Larger prospective studies are warranted to further evaluate the efficacy and safety of TKIs in patients with VHL disease.

Hemangioblastoma Instead of Renal Cell Carcinoma Plays a Major Role in the Unfavorable Overall Survival of Von Hippel-Lindau Disease Patients

Von Hippel-Lindau (VHL) disease is a hereditary cancer syndrome characterized by poor survival. The effect of the involvement of each organ on survival remains unclear. Our study aimed to study the effect of the involvement of each organ on survival in VHL disease patients. We retrospectively analyzed 336 patients from 125 families. The onset age was compared between different groups using Mann-Whitney U test and Kruskal-Wallis test. Univariate and multivariate time-dependent Cox regression analyses were conducted to evaluate how survival was influenced by the involvement of each organ. The median survival time for VHL disease patients was 66 years. The onset age was earlier in the central nervous system (CNS) group than in the abdominal group. The involvement of central nervous system hemangioblastoma (CHB) and retinal hemangioblastoma (RA) were independent risk factors for overall survival. The involvement of renal cell carcinoma (RCC) was not a significant risk factor for overall survival. Only RA was a risk factor for CHB-specific survival. This study analyzed the relationship between organ involvement and survival of VHL patients. This may help guide future genetic counseling and clinical decision-making.

Minimally invasive resection of spinal hemangioblastoma: feasibility and clinical results in a series of 18 patients

OBJECTIVE

Hemangioblastomas are benign, highly vascularized tumors that can occur sporadically or as part of von Hippel-Lindau (VHL) disease. Traditionally, spinal hemangioblastomas have been surgically treated via an open approach. In recent years, however, minimally invasive techniques using tubular retractors have been increasingly applied in spine surgery. Such procedures involve less tissue trauma but are also particularly demanding for the surgeon, especially in cases of highly vascular tumors such as hemangioblastomas. The object of this study was to evaluate the safety and efficacy of minimally invasive resection of selected spinal hemangioblastomas.

METHODS

The authors conducted a retrospective single-center study of all patients who, between January 2010 and January 2018, had been operated on for spinal hemangioblastoma via a minimally invasive approach performed at the surgeon's discretion. The surgical technique is described and the pre- and postoperative neurological and imaging results were analyzed descriptively. The primary outcome was the postoperative compared to preoperative neurological condition (McCormick grade). The secondary outcomes were the extent of tumor resection and postoperative complications.

RESULTS

Eighteen patients, 12 female and 6 male, harboring a total of 19 spinal hemangioblastomas underwent surgery in the study period. Seventeen patients had stable neurological findings with stable or improved McCormick grades (94.5%) at a mean of 4.3 months after surgery. One (5.5%) of the 18 patients developed progressive neurological symptoms with a worsened McCormick grade that did not improve in the long-term follow-up. Sixteen of the 18 patients had VHL disease, whereas 2 patients had sporadic spinal hemangioblastomas. In all patients, postoperative MRI showed complete resection of the tumors. No other surgery-related perioperative or postoperative complications were recorded.

CONCLUSIONS

A minimally invasive approach for the resection of selected spinal hemangioblastomas is safe and allows complete tumor resection with good clinical results in experienced hands.

A focused 35-minute whole body MRI screening protocol for patients with von Hippel-Lindau disease

BACKGROUND

Von Hippel-Lindau (VHL) disease is an autosomal dominantly inherited tumor syndrome. Affected patients develop central nervous system hemangioblastomas and abdominal tumors, among other lesions. Patients undergo an annual clinical screening program including separate magnetic resonance imaging (MRI) of the brain, whole spine and abdomen. Consequently, patients are repeatedly subjected to time-consuming and expensive MRI scans, performed with cumulative Gadolinium injections. We report our experience with a 35-min whole body MRI screening protocol, specifically designed for detection of VHL-associated lesions.

METHODS

We designed an MRI protocol dedicated to the typical characteristics of VHL-associated lesions in different imaging sequences, within the time frame of 35 min. Blank imaging of the abdomen is carried out first, followed by abdominal sequences with Gadolinium contrast. Next, the full spine is examined, followed by imaging of the brain. A single dose of contrast used for abdominal imaging is sufficient for further highlighting of spine- and brain lesions, thus limiting the Gadolinium dosage. We used 1.5 Tesla equipment, dealing with fewer artifacts compared to a 3 Tesla system for spine- and abdominal imaging, while preserving acceptable quality for central nervous system images. In addition, imaging on a 1.5 Tesla scanner is slightly faster.

RESULTS

From January 2016 to November 2018, we performed 38 whole body screening MRIs in 18 VHL patients; looking for the most common types of VHL lesions in the abdomen, spine, and brain, both for new lesions and follow-up. The one-step approach MRI examinations lead to 6 surgical interventions for clinically significant or symptomatic hemangioblastomas in the brain and spine. One renal cell carcinoma was treated with radiofrequency ablation. In comparison with previous conventional MRI scans of the same patients, all lesions were visible with the focused protocol.

CONCLUSIONS

Annual screening in VHL disease can be done in a rapid, safe and sensitive way by using a dedicated whole body MRI protocol; saving MRI examination time and limiting Gadolinium dose.

Von Hippel-Lindau Disease

Phakomatoses (phakoma = birthmark) are a group of diseases or syndromes that have hamartomas (tumorous malformations composed of tissues normally present at the location where they develop) of the skin, brain, and eye (oculoneurocutaneous syndromes).