Hemangioblastomas of the cauda equina: Clinical features and long-term surgical outcomes

BACKGROUND

Spinal hemangioblastomas (HBs) that involving cauda equina are rare. Data on clinical characteristics and long-term intervention outcomes of patients harboring cauda equina HBs remain lacking due to its scarcity.

OBJECTIVE

This study aims to present the clinical-radiological features and treatment results of this rare pathology by using cases from a single center.

METHODS

A review of demographic data and intervention outcomes of patients harboring cauda equina HBs in our department between 2009 and 2020 was retrospectively carried out.

RESULTS

Ten consecutive adult patients were incorporated, with a slight female predominance (n = 6, 60%). The mean age was 39.9 ± 14.7 (range: 18-58) years. Six patients (60%) had von Hippel‒Lindau (VHL) syndrome and showed multiple symptoms and severe neurological deficits, while 4 (40%) were in the sporadic group and only presented pain symptoms. During follow-up, 3 patients (30%) experienced lesion relapse and underwent repeated surgery. Favorable outcomes were achieved in all patients.

CONCLUSION

Cauda equina HBs are rare spinal vascular lesions that should be differentiated from other lumbar canal lesions. Total surgical resection is the main treatment modality and can benefit patients, even recurrent patients. The treatment outcome is usually satisfactory, especially in sporadic cases.

[A case of von Hippel-Lindau syndrome with optic disc pit and macular hole]

A 69-year-old female patient presented to the ophthalmology department with complaints of blurred vision in the left eye for more than 10 days. Her medical history revealed a history of right renal tumor and left pheochromocytoma, which were treated with surgical resection at an external institution. Ophthalmic examination revealed a temporal superior cup-shaped optic disc pit in the left eye, along with a macular hole approximately 1/5 the size of the optic disc diameter in the macular region. Additionally, peripheral retinal examination at the 6 o'clock and 11 o'clock positions showed vascular tumors, each approximately 1.5 times the size of the optic disc diameter. Based on the patient's medical history, fundus findings, and auxiliary examination results, a diagnosis of macular hole in the left eye, optic disc pit in the left eye, and Von Hippel-Lindau (VHL) syndrome was established. Subsequently, the patient underwent left vitrectomy and macular hole repair surgery, leading to an improvement in visual acuity.

A bibliometric analysis of the top 100 cited articles for hemangioblastoma of the central nervous system

Hemangioblastoma is a rare benign tumor that can affect the central nervous system sporadically or in association with von Hippel-Lindau (VHL) syndrome. Despite the advances in the medical field, hemangioblastoma still has a significant morbidity and mortality burden. This review gathered and analyzed this entity's top one hundred cited articles. The Scopus database was screened using the following keywords ("Hemangioblastoma" OR "Haemangioblastoma" OR "Hemangioblastomata"). The results were sorted by citation count, highest to lowest. Articles discussing hemangioblastoma of the central nervous system were included. Two independent reviewers extracted the article-, author-, and Journal-based data. Articles were classified into four categories: clinical features/ natural history, treatment, histopathology, review, or radiology. The location, brain, spine, or both, and type, sporadic, VHL-associated, or both, were used to classify the articles. The search query resulted in 4023 articles, and the top 100 most cited articles were included. The number of citations totaled 8781, averaging 87.81 CC per article. The included papers were published in 41 different journals between 1952 and 2014 by more than 11 departments from 65 institutions and 16 countries. The number of citations ranged from 46 to 333. The peak publication activity was before the 2000s, contributing to 62% of all articles, and the most prolific decade was 1990-2000, with 37 publications. We conducted a comprehensive bibliometric analysis of data from the most influential publications on central nervous system hemangioblastoma. We identified publication dynamics and research gaps. More high-impact studies are warranted to enhance disease comprehension and management.

Hemangioblastoma with late leptomeningeal metastasis: a case report

BACKGROUND

Hemangioblastoma of the central nervous system is an uncommon benign neoplasm, with about 25% of cases in patients with von Hippel-Lindau disease. The incidence of metastasis is rare, particularly in patients without von Hippel-Lindau disease. We report a case of hemangioblastoma with leptomeningeal dissemination as a late recurrence.

CASE PRESENTATION

A 65-year-old Caucasian man with a history of World Health Organization grade I hemangioblastoma of the cerebellar vermis underwent gross total resection in 1997. In early 2018, he developed intracranial recurrences with diffuse leptomeningeal disease of the entire spine. The patient underwent resection of intracranial recurrence, followed by palliative craniospinal irradiation. The disease progressed quickly, and he died 8 months after recurrence.

CONCLUSIONS

Despite a benign pathology, hemangioblastoma has a low risk of metastasis. The outcome for hemangioblastoma patients with metastasis is poor. Multidisciplinary care for patients with metastatic hemangioblastoma warrants further investigation, and an effective systemic option is urgently needed. Regular lifelong follow-up of at-risk patients is recommended.

Brain and/or Spinal Cord Tumors Accompanied with Other Diseases or Syndromes

Several medical conditions that interest both the brain and the spinal cord have been described throughout the history of medicine. Formerly grouped under the term Phacomatosis because lesions of the eye were frequently encountered or genodermatosis when typical skin lesions were present, these terms have been progressively discarded. Although originally reported centuries ago, they still represent a challenge for their complexity of cure. Nowadays, with the introduction of advanced genetics and the consequent opportunity of whole-genome sequencing, new single cancer susceptibility genes have been identified or better characterized; although there is evidence that the predisposition to a few specific tumor syndromes should be accounted to a group of mutations in different genes while certain syndromes appeared to be manifestations of different mutations in the same gene adding supplementary problems in their characterization and establishing the diagnosis. Noteworthy, many syndromes have been genetically determined and well-characterized, accordingly in the near future, we expect that new targeted therapies will be available for the definitive cure of these syndromes and other gliomas (Pour-Rashidi et al. in World Neurosurgery, 2021). The most common CNS syndromes that will be discussed in this chapter include neurofibromatosis (NF) types 1 and 2, von Hippel-Lindau (VHL) disease, and tuberous sclerosis complex (TSC), as well as syndromes having mostly extra-neural manifestations such as Cowden, Li-Fraumeni, Turcot, and Gorlin syndromes.

Central nervous system hemangioblastomas in von Hippel-Lindau disease: Total growth rate and risk of developing new lesions not associated with circulating VEGF levels

BACKGROUND

Hemangioblastomas of the central nervous system are a prominent feature of von Hippel-Lindau-disease (vHL). Hemangioblastomas are known to secrete vascular endothelial growth factor (VEGF), suggesting a potential role of VEGF as a biomarker for tumor growth.

METHODS

Plasma VEGF samples from 24 patients with von Hippel-Lindau disease were analyzed by solid-phase proximity ligation assay (PLA). Levels were monitored over time together with numeric and volumetric CNS tumor burden, and compared to plasma VEGF levels in healthy controls.

RESULTS

The mean yearly progression in tumor volume was 65.5%. Yearly risk of developing one or several new CNS tumor(s) was 50%. No significant correlation between tumor burden and levels of VEGF was seen. VEGF levels in patients (31.55-92.04; mean 55.83, median 56.41) as measured by immunodetection in a solid-phase PLA did not differ significantly from controls (37.38-104.56; mean 58.89, median 54.12) (p = 0,266).

CONCLUSION

The increase in total CNS tumor volume in vHL occurred in a saltatory manner. The risk of developing a new lesion was 50% per year. We found no evidence for VEGF secretion from CNS hemangioblastomas in vHL in circulating blood. Other potential biomarkers should be explored to assess progression of tumor burden in vHL.

Primary and secondary retinal capillary haemangioma in Mexico

A series is presented of sixteen cases of retinal capillary haemangioma (RCH) from consecutive patients at an ophthalmology teaching hospital in Mexico City. There were seven primary haemangioblastomas, and nine due to von Hippel-Lindau disease (VHL). All cases associated with VHL already had systemic manifestations, such as, cerebellar, medullary and renal tumours. Treatment of capillary haemangiomas must be individualised, based on several factors, including the number of lesions, exudation, or presence of retinal detachment. A multidisciplinary approach is essential.

The endolymphatic sac tumor: challenges in the eradication of a localized disease

OBJECTIVE

Identify the critical points that lead to recurrences and lack of radicality in endolymphatic sac tumors (ELSTs).

STUDY DESIGN

Retrospective case study and review of the literature.

SETTING

Tertiary referral center.

PATIENTS

Thirteen cases of ELST were included in the study and their preoperative, intraoperative and postoperative data were analyzed and compared to a review of the literature.

INTERVENTION(S)

Therapeutical.

MAIN OUTCOME MEASURE(S)

Prevalence of recurrent and residual tumors, comparison to the literature and analysis of ELST characteristics.

RESULTS

Diagnosis was made 26 ± 17 months after the onset of symptomatology, and an ELST was preoperatively suspected in only six cases. At the time of surgery, 10 patients suffered from hearing loss. Preoperative symptoms or audiometry could not predict labyrinth infiltration, although speech discrimination scores were significantly associated with labyrinth infiltration (p = 0.0413). The labyrinth was infiltrated in 8 cases (57.1%), and in 7 cases (46.7%) the tumor eroded the carotid canal, whereas 6 cases (40%) presented an intradural extension. A gross total resection was achieved in 11 cases. There were two residual tumors, one of which because of profuse bleeding, and one recurrence (23.1%). A mean of 22.8% of recurrent or residual tumors are described in the literature based on 242 published cases, in more than half of the cases as a consequence of subtotal tumor resection (STR).

CONCLUSIONS

Recurrence derives mostly from the difficulty to identify the extension of the tumor due to the extensive bone infiltration. Accurate diagnosis and correct preoperative planning, with embolization when possible, will facilitate surgery and avoid STR due to intraoperative bleeding. Long follow-ups are important in order to avoid insidious recurrences.

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.

Phacomatoses in the pediatric age group

The most common phacomatoses in children that need surgical attention are neurofibromatosis 1 and 2, tuberous sclerosis complex, Sturge-Weber disease, Von Hippel-Lindau disease, and neurocutaneous melanocytosis. All are rare and, as genetically determined disorders, all complex multisystem diseases with multiple manifestations outside the CNS. Diagnostics, management recommendations, and surgical care are age-specific and require individualization. The lifelong multidimensional disease burden demands a multidisciplinary and well-coordinated management approach. The consequence of these boundary conditions is that management of children with a phacomatosis is everything else but simple, straight forward, and intuitive. This Special Annual Issue is designed to serve as an up-to-date encyclopedic reference for all aspects of management of phacomatoses in the pediatric age group.

Von Hippel-Lindau disease and Sturge-Weber syndrome

The primary neurologic involvement in both von Hippel-Lindau (VHL) disease and Sturge-Weber syndrome (SWS) is vascular tumor/vascular malformation, but molecular pathogenesis, long-term symptom evolution, and treatment are quite different. VHL is caused by dominant inherited or de novo germline mutations, while SWS is caused by somatic mosaicism. A diagnosis of VHL carries substantial cancer risk, while the clinical issues in SWS are primarily related to the consequences of the intracranial vascular abnormalities.

[Papillary cystadenoma of the epididymis: a report of 2 cases and review of the literature]

OBJECTIVE

To study the clinicopathological characteristics of papillary cystadenoma of the epididymis.

METHODS

Using routine pathology and immunohistochemistry, we observed the surgically obtained samples from 2 cases of papillary cystadenoma of the epididymis, analyzed their pathological features and clinical presentations, and reviewed the related literature.

RESULTS

The 2 patients were both adult males. The tumors typically manifested as painless swelling in the epididymis, with occasionally dull pain and tenesmus in 1 of the cases. Pathologically, the lesions exhibited three morphological features, i. e., dilated ducts and small cysts surrounded by fibrous connective tissue, adenoid papillary hyperplasia into the cysts embraced by fibrovascular stroma, and acidophil substance present in the cysts. Immunohistochemistry showed that the tumors were strongly positive for CK8/18, CK7, and EMA, but negative for CK20, CEA, MC, Calretenin, P53, P63, SMA, VHL, and CD10, with the positive rate of Ki-67 <1%. Follow-up visits revealed good prognosis in both cases.

CONCLUSION

Papillary cystadenoma of the epididymis is a rare benign tumor in the male urogenital system, which may be accompanied by the VHL syndrome. Surgery is the first choice for its treatment.

[Basic science and clinical aspects of familial brain tumors]

Familial brain tumor syndromes include neurofibromatosis 1, neurofibromatosis 2, tuberous sclerosis, von Hippel-Lindau disease, and multiple endocrine neoplasia type 1, which are hereditary diseases. In these diseases, various tumors develop because of alterations in tumor suppressor genes. Familial brain tumors are mostly benign, but some are malignant. Familial brain tumor syndromes are diagnosed on the basis of guidelines for clinical diagnosis and by DNA test. Unlike sporadic brain tumors, familial brain tumors occur at multiple sites; therefore, a single operation is often not sufficient for treating familial brain tumors, and it is often necessary to treat lesions in other organs. Surgical indications should be considered more prudently for familial brain tumors than for sporadic brain tumors.

An Immunohistochemical and Ultrastructural Study of Pancreatic Microcystic Serous Cyst Adenoma with Special Reference to Tumor-Associated Microvasculature and Vascular Endothelial Growth Factor in Tumor Cells

Pancreatic microcystic serous cyst adenomas are rare exocrine tumors composed of small cysts lined by glycogen-rich cells. The disease may be sporadic or present as part of von Hippel-Lindau (VHL) syndrome. Four sporadic cases of pancreatic serous cyst adenoma were examined by conventional histological, immunohistochemical, and ultrastructural methods. In the present study, new findings include the immunohistochemical identification of vascular endothelial growth factor (VEGF) and the lack of PDX-1 (putative master transcriptional factor in pancreatic stem cells) in the epithelial tumor cells. Ultrastructurally, many small blood vessels were intimately associated with epithelial tumor cells and adjacent fibroblastic cells. The observations suggest the possibility that VEGF-containing tumor cells act in a paracrine fashion to stimulate neovascularization; that peripheral blood in the vascular lumen might be filtered or processed by the endothelial and epithelial tumor cells; and that filtrates might therefore be stored as serous inclusions. It is hypothesized that pancreatic serous cyst adenomas might be under the abnormal regulation of the VHL gene, just like VHL disease itself and certain types of renal cell carcinoma, showing the distinctive histology of a rich vascularity intimately related to epithelial lining cells of cysts accompanied by stromal fibroblasts/myofibroblasts and collagenous stroma.

Ranibizumab, a mAb against VEGF-A for the potential treatment of age-related macular degeneration and other ocular complications

Genentech Inc and Novartis Ophthalmics AG have developed and launched the humanized anti-VEGF antibody fragment ranibizumab, a 48-kDa humanized antibody fragment that inhibits all forms of biologically active VEGF-A, for the treatment of age-related macular degeneration by intravitreal administration. Phase I to III clinical trials to confirm the role of ranibizumab in the treatment of choroidal neovascularization (phase II and III), diabetic macular edema (phase II and III), retinal venous occlusion (phase II and III), telangiectasia (phase I and II), central serous chorioretinopathy (phase I), polypoidal choroidal vasculopathy (phase I/II), conjunctival neoplasms (phase I) and von Hippel-Lindau syndrome (phase I) are ongoing.

Supratentorial dural-based hemangioblastoma not associated with von Hippel Lindau complex

Hemangioblastomas are rarely found in a supratentorial location and are commonly associated with the von Hippel-Lindau complex. Therefore, patients with such tumors must be evaluated for both other hemangioblastomas within the central nervous system as well as for this complex via physical examination, radiographic examination, and genetic testing. We report the seventh case of a patient with an isolated supratentorial dural based hemangioblastoma not associated with the von Hippel-Lindau complex.

Kapilläre Hämangiome der Netzhaut beim Von-Hippel-Lindau-Syndrom

Thermal photocoagulation of small peripheral angiomas is the treatment of choice for capillary hemangiomas in patients with von Hippel-Lindau disease. Larger peripheral angiomas are better treated with beta-ray brachytherapy resulting in improved results in terms of local tumor control and the side effects of treatment. Photodynamic treatment is an alternative option in the management of capillary hemangiomas of the retina. Further improvement of the treatment results of photodynamic therapy may be achieved by combination with intravitreal drugs. External beam radiation using either stereotactic techniques or proton radiation must be considered as experimental. The treatment of juxtapapillary angiomas is still a therapeutic dilemma. Vitreoretinal surgery should be confined to advanced stages with tractional detachment or when no other treatment option is available to salvage the eye.

Spinal hemangioblastoma containing metastatic renal cell carcinoma in von Hippel—Lindau disease

✓ The authors describe the case of a patient with von Hippel—Lindau (VHL) disease in which a spinal hemangioblastoma contained metastatic renal cell carcinoma (RCC). The literature on tumor-to-tumor metastasis associated with VHL disease of the central nervous system (CNS) is reviewed.

Midthoracic back pain developed in this 43-year-old man with a left-sided radicular component 2 years after he underwent resection of a left RCC. Radiological findings demonstrated a T6–7 intradural intramedullary lesion. A T5–8 laminectomy and gross-total resection of the spinal cord mass were performed. Light and electron microscopic examination showed features of hemangioblastoma, which contained metastatic foci of RCC. Genetic analysis demonstrated the presence of a deleting mutation in the first exon (nt. 394–406) of the VHL locus, truncating 16 amino acids (N61–77) from the first beta sheet in the VHL protein. A review of the literature revealed that RCC-to-CNS hemangioblastoma is the second most common donor—recipient tumor association among the tumor-to-tumor metastases.

Molecular genetic analysis of a supratentorial haemangioblastoma in a non-Von Hippel Lindau patient

We describe a rare tumor site in a 46 year old man who presented with a two week history of headache. Physical examination revealed bilateral papilloedema with no other localizing signs. Computed Tomographic Scan as well as Magnetic Resonance Imaging of the brain revealed a lesion with a dura tail located adjacent to the falx cerebri of the right frontal lobe. This lesion was not invading the inner table of the skull base. A tumor blush was seen on angiogram. There were no abnormalities on CT scan of the abdomen and fundoscopy was normal. Intraoperatively a vascular tumor not attached to the dura was noted and removed totally. Histopathological examination was typical of a hemangioblastoma. Analysis revealed no mutations of the VHL gene in 5 regions, exon 5-8 of the p53 gene, exon 1-2 of the p16 gene and exon 5,6 and 8 of the PTEN gene. This is the first case report of a supratentorial hemangioblastoma in a non-Von Hippel Lindau patient with genetic evidence.

Coexpression of erythropoietin and its receptor in endolymphatic sac tumors

Object. Von Hippel—Lindau (VHL) disease is characterized by multiple tumors in specific organs. The cell of origin and the reason for the particular organ distribution of the tumors remains unknown. Endolymphatic sac tumor (ELST) is one of the lesions associated with VHL disease. Data from previous studies of VHL disease—associated hemangioblastomas (HBs) and renal cell carcinomas (RCCs) have indicated that VHL gene deficiency causes coexpression of erythropoietin (Epo) and its receptor (Epo-R), which facilitates tumor growth.

Methods. The authors studied ELSTs from five patients with VHL germline mutations. Analysis of the five ELST samples revealed loss of the wild-type allele, consistent with Knudson's two-hit hypothesis for tumorigenesis. All five ELST specimens were characterized microscopically and by immunohistochemical analysis. Coexpression of Epo and Epo-R was found in all five tumors on immunohistochemical studies and confirmed through reverse transcription—polymerase chain reaction and Western blot analysis.

Conclusions. Expression of Epo appears to be a result of VHL gene deficiency, whereas the simultaneous coexpression of Epo-R may reflect a developmental mechanism of tumorigenesis. Coexpression of Epo and Epo-R in ELSTs together with the morphological and genetic similarities of these lesions with other VHL disease—associated tumors indicates that VHL disease—associated tumors in different organs share common pathogenetic pathways.

Complete radiological and metabolic response of metastatic renal cell carcinoma to SU5416 (semaxanib) in a patient with probable von Hippel-Lindau syndrome

We report a case of a patient with probable von Hippel-Lindau (VHL) syndrome and metastatic renal cell cancer (RCC) who had a complete radiological and metabolic response to SU5416 (semaxanib). The patient was enrolled on a clinical study examining the efficacy of SU5416 in patients with metastatic cancer. Treatment with SU5416 was given at a dose of 145 mg/m2 intravenously twice-weekly for 11 doses. The patient achieved an early metabolic response on an F-18 fluorodeoxyglucose (FDG) Positron Emission Tomographic (PET) scan within 2 weeks of therapy. Subsequent computerized tomography (CT) and PET scans (9 and 12 months after treatment, respectively) confirmed ongoing complete radiological and metabolic response. He remains tumor-free 18 months after treatment. This is the first documented report of metastatic RCC in the setting of presumed VHL syndrome responding to treatment with SU5416. While vascular endothelial growth factor (VEGF) inhibitors have been shown to produce a modest response in sporadic metastatic RCC, further studies utilizing VEGF inhibitors in patients with VHL syndrome and RCC warrants exploration.

Hereditary kidney cancer

Significant advances have been made in the understanding of the genetic basis of familial renal neoplasia. Identification of key genes in the pathogenesis of various hereditary renal cancer syndromes has provided opportunities to screen family members at risk and to explore the significance of these genetic abnormalities in the development and genesis of much more common sporadic counterparts. As researchers continue to delineate critical carcinogenic pathways and accumulate expansive knowledge on oncogenic mechanisms driving cancer initiation and progression at the cellular and molecular levels, this information will be integrated and translated into effective diagnostic and therapeutic strategies that will dictate clinical management of all renal cancers.

Molecular detection of von Hippel-Lindau gene mutations in urine and lymph node samples in patients with renal cell carcinoma: potential biomarkers for early diagnosis and postoperative metastatic status

PURPOSE

Organ confined renal cell carcinoma can be cured in the majority of patients, whereas more extensive lesions have a poor prognosis. Therefore, the development of a useful biomarker for early diagnosis as well as postoperative metastatic status would contribute to the appropriate therapy for renal cell carcinoma. To diagnose renal cell carcinoma preoperatively we developed a novel urinary test and detected occult lymph node micrometastasis using a molecular approach.

MATERIALS AND METHODS

Urine samples were obtained preoperatively from 27 patients with renal cell carcinoma and von Hippel-Lindau (VHL) gene mutations in the tumors, and were analyzed for VHL gene mutations using a nested single strand conformational polymorphism analysis. Lymph nodes without evidence of histological metastasis were obtained from 15 patients with renal cell carcinoma and VHL gene mutations, and analyzed for VHL gene mutations using mutation specific nested reverse transcription polymerase chain reaction method.

RESULTS

In urine samples 5 of 27 VHL gene mutations (18.5%) were found and each mutation pattern was the same as that detected in each renal cell carcinoma. One lymph node micrometastasis was found.

CONCLUSIONS

These data indicate the presence of detectable levels of tumor derived DNA in the urine of patients with renal cell carcinoma and suggest that nested single strand conformational polymorphism analysis of VHL gene of urine samples provides a possible tool for the early detection of renal cell carcinoma. Furthermore, mutation specific nested reverse transcription polymerase chain reaction is useful to detect occult lymph node micrometastasis and may predict patients at risk for local recurrence. These 2 combined approaches using VHL gene mutations may contribute to the total therapy for and prognosis of renal cell carcinoma.

Absence of mutations in the VHL gene but frequent loss of heterozygosity at 3p25-26 in non-small cell lung carcinomas

In this study we have examined 79 primary non-small cell lung tumours for the presence of mutations of the VHL gene as well as for allelic imbalance at the gene surrounding loci. While allelic imbalance was found in 83% of specimens, frequently affecting the whole 3p25-p26 region, no mutations were detected in the VHL coding region. The fractional regional loss (FRL) was significantly higher in squamous cell carcinomas (0.746) than adenocarcinomas (0.493) (Wilcoxon P=0.002). This is the first investigation of the VHL gene mutational status in primary lung tumours. Our results indicate that mutation is not a common means of VHL inactivation in NSCLC.

Von Hippel-Lindau disease

Von Hippel-Lindau (VHL) disease is an uncommon, autosomal dominant hereditary multitumor syndrome caused by germline alterations of the VHL gene, which has been cloned recently and identified as a tumor suppressor gene. The major lesions in VHL disease include hemangioblastomas in the central nervous system and retina, clear cell renal cell carcinomas, pheochromocytomas, pancreatic tumors, epididymal cystadenomas, endolymphatic sac tumors, carcinoid tumors, and multiple cysts of the kidney, pancreas, and epididymis. Compared with sporadic ones, the tumors in VHL disease develop at an earlier age and often multifocally. Histologic features of VHL tumors are characterized by their high degree of vascularization and the presence of a clear cell component. Hypervascularization is induced by overexpression of vascular endothelial growth factor (VEGF), and because the principal function of VHL protein is the negative regulation of hypoxia-inducible mRNAs including VEGF mRNA, inactivation of VHL gene plays critical roles in angiogenesis of the VHL tumors. In addition, since VHL protein is also required for the down-regulation of transcription activity of certain genes for the cell growth and cell cycle, inactivation of VHL gene may contribute to tumorigenesis of the VHL tumors. A significant difference in the frequency of types of VHL gene mutation has been noted among the affected families, known as the genotype-phenotype correlations.

The von Hippel-Lindau protein interacts with heteronuclear ribonucleoprotein a2 and regulates its expression

The product of the von Hippel-Lindau (VHL) tumor suppressor gene, pVHL, functions as a ubiquitin-protein isopeptide ligase in regulating HIF-1 protein turnover, thus accounting for the increased transcription of hypoxia-inducible genes that accompanies VHL mutations. The increased vascular endothelial growth factor mRNA stability in cells lacking pVHL has been hypothesized to be due to a similar regulation of an RNA-binding protein. We report the expression of the GLUT-1 3'-untranslated region RNA-binding protein, heteronuclear ribonucleoprotein (hnRNP) A2, is specifically increased in pVHL-deficient cell lines. Enhanced hnRNP A2 expression was apparent in all cell fractions, including polysomes, where a similar modest effect on hnRNP L (a GLUT-1 and VEGF 3'-untranslated region-binding protein), was seen. Steady state levels of hnRNP A2 mRNA were unaffected. Regulation of hnRNP A2 levels correlated with the ability of pVHL to bind elongin C. Proteasome inhibition of cells expressing wild type pVHL selectively increased cytoplasmic hnRNP A2 levels to that seen in pVHL-deficient cells. Finally, an in vivo interaction between pVHL and hnRNP A2 was demonstrated in both the nucleus and the cytoplasm. Collectively, these data indicate that hnRNP A2 expression is regulated by pVHL in a manner that is dependent on elongin C interactions as well as functioning proteasomes.

Role of transforming growth factor-alpha in von Hippel--Lindau (VHL)(-/-) clear cell renal carcinoma cell proliferation: a possible mechanism coupling VHL tumor suppressor inactivation and tumorigenesis

Mutations of the VHL tumor suppressor gene occur in patients with VHL disease and in the majority of sporadic clear cell renal carcinomas (VHL(-/-) RCC). Loss of VHL protein function is associated with constitutive expression of mRNAs encoding hypoxia-inducible proteins, such as vascular endothelial growth factor. Overproduction of angiogenic factors might explain why VHL(-/-) RCC tumors are so highly vascularized, but whether this overproduction is sufficient for oncogenesis still remains unknown. In this report, we examined the activity of transforming growth factor-alpha (TGF-alpha), another VHL-regulated growth factor. We show that TGF-alpha mRNA and protein are hypoxia-inducible in VHL(-/-) RCC cells expressing reintroduced VHL. In addition to its overexpression by VHL(-/-) RCC cells, TGF-alpha can also act as a specific growth-stimulatory factor for VHL(-/-) RCC cells expressing reintroduced wild-type VHL, as well as primary renal proximal tubule epithelial cells, the likely site of origin of RCC. This role is in contrast to those of other growth factors overexpressed by VHL(-/-) RCC cells, such as vascular endothelial growth factor and TGF-beta1, which do not stimulate RCC cell proliferation. A TGF-alpha-specific antisense oligodeoxynucleotide blocked TGF-alpha production in VHL(-/-) RCC cells, which led to the dependence of those cells on exogenous growth factors to sustain growth in culture. Growth of VHL(-/-) RCC cells was also significantly reduced by a drug that specifically inhibits the epidermal growth factor receptor, the receptor through which TGF-alpha stimulates proliferation. These results suggest that the generation of a TGF-alpha autocrine loop as a consequence of VHL inactivation in renal proximal tubule epithelial cells may provide the uncontrolled growth stimulus necessary for the initiation of tumorigenesis.

Management and extended outcome of patients with synchronous bilateral solid renal neoplasms in the absence of von Hippel-Lindau disease

OBJECTIVE

To gain information regarding long-term follow-up in patients with synchronous bilateral solid renal neoplasms in whom renal-preserving surgery is imperative.

PATIENTS AND METHODS

We examined our surgical experience and the survival outcome, as evaluated by Kaplan-Meier and log-rank analysis, of 94 patients (64 men and 30 women) who presented to the Mayo Clinic in Rochester, Minn, from 1973 to 1998 with bilateral synchronous solid renal neoplasms in the absence of von Hippel-Lindau disease. Follow-up of these patients ranged from 1 to 25 years, with a mean of 5.86 years and a median of 4.18 years. Tumors were staged according to the TNM classification. Pathologic staging and grading were usually performed on the kidney with the most extensive cancer. The Cox proportional hazards model was used to assess the relationship of grade (1-4), tumor size, and enucleation as opposed to extended (1 cm) partial nephrectomy on overall, cancer-specific, local recurrence-free, and metastasis-free survival.

RESULTS

Seventy-one patients (76%) had bilateral synchronous renal cell carcinoma, and 14 patients (15%) had a unilateral renal cell carcinoma with a contralateral benign solid neoplasm. Nine patients (10%) had bilateral benign solid lesions. Sixty-six patients (70%) underwent a single procedure, whereas 28 (30%) underwent staged surgical procedures. Fifty-one patients (54%) are alive, and 43 (46%) have died. Twenty patients (21%) died of metastatic disease, and 5 (5%) had a local recurrence. Cancer-specific survival of the 85 patients with at least 1 renal cell carcinoma still under observation was 81% (+/- 4.9% SE) and 59% (+/- 8.1% SE) at 5 and 10 years, respectively, and survival to local recurrence was 96% (+/- 2.6% SE) at 5 years and 93% (+/- 3.7% SE) at 10 years with 14 patients still under observation. Grade 3 was a statistically significant factor for metastasis (P < .001). A significant difference in metastasis-free survival and cancer-specific survival was noted dependent on pathologic T stage (P < .001 and P = .02, respectively), with patients with local pT3 disease having a higher rate of metastasis and cancer-specific death. Multivariate analysis revealed that tumor grade was associated with metastasis-free survival (P = .002) and tumor size with cancer-specific survival (P = .04). There was no statistical significance on survival outcome end points according to procedure performed, i.e., enucleation vs extended partial nephrectomy.

CONCLUSION

Long-term results of renal-preserving procedures for a series of patients with bilateral solid renal neoplasms indicate that grade, stage, and tumor size are significant predictors of outcome. Mean follow-up of over 5 years supports nephron-sparing techniques in selected patients because local recurrence was infrequent compared with distant metastasis.

Renal cell carcinoma in children with diffuse cystic hyperplasia of the kidneys

We report the clinical, pathologic, and genetic features of renal malignancy in two children with diffuse cystic hyperplasia. Both presented with massive bilateral nephromegaly. Neither had a family history or clinical findings suggestive of tuberous sclerosis or von Hippel-Lindau disease. The kidneys of both children were extensively replaced by tubulocystic hyperplasia with large eosinophilic epithelial cells. The masses of hyperplastic tissue were nodular, compressing remnants of uninvolved renal parenchyma. Tubulopapillary carcinoma was present in both children, one of whom had bilateral multicentric carcinoma. No loss of heterozygosity was detected in the tumors at the TSC1, TSC2, or VHL gene regions, and no alterations in the VHL gene were detected using single-strand conformation polymorphism analysis. These cases of bilateral renal enlargement with diffuse cystic hyperplasia appear to represent a new clinical syndrome that may warrant bilateral nephrectomy because of the risk of malignancy.

[A case of papillary cystadenoma of the epididymis]

We report a case of papillary cystadenoma of the right epididymis in a 48-year-old man. He consulted our hospital complaining of a small, painless mass at the upper pole of the right testis. There did not seem to be any remarkable problem of the mass. At 52 years old, the mass caused him pain, we diagnosed this case as chronic epididymitis, and performed right epididymectomy. On cut section, the tumor was multicystic and well encapsulated. The fluid within the cystic spaces was hemorrhagic. Microscopically, multimicrocysts were covered by tumor cells, which did not show any atypism or mitotic features. A papillary growth pattern was formed by vacuolated tumor cells around the capillaries in the microcysts, and a diagnosis of papillary cystadenoma of the epididymis was made. Papillary cystadenoma of the epididymis is considered a comparatively uncommon disease. To our knowledge, about 50 cases have been reported in the world literature, and this is the 17th case in Japan. Histologically, this tumor is similar in appearance to well-differentiated renal cell carcinoma, so it should be differentiated from metastatic renal cell carcinoma and multicystic papillary adenocarcinoma of the rete testis. The patient remains well with no evidence of recurrence or complication 8 months after excision. There is no evidence of renal cell carcinoma, nor features of von Hippel-Lindau's disease in this patient or his family.

Clinical management of the multiple endocrine neoplasia syndromes: results of a computerized opinion poll at the Sixth International Workshop on Multiple Endocrine Neoplasia and von Hippel-Lindau disease

OBJECTIVES AND DESIGN

In order to provide all participants of the Sixth International Workshop on Multiple Endocrine Neoplasia and von Hippel-Lindau Disease with the opportunity to express their opinion on medical, ethical and social issues on clinical management of these hereditary cancer syndromes, a meeting employing an interactive voting system was organized.

RESULTS

In many aspects, the majority of the participants shared the same opinion. The following percentages of participants felt that, if a specific germline mutation is present in a definitely affected family member, DNA diagnosis should be performed in the offspring of this patient before the age of 10: 78% for MEN-1, 93% for MEN-2, and 71% for VHL. About 71% felt the clinical specialist should provide information about the consequences of DNA analysis and be responsible for disclosing the DNA test results and performing genetic counselling. If possible, selective surgery is preferred to maintain organ function. To make a complete diagnosis in a patient with an apparently sporadic tumour, 89% believed that mutation analysis of germline DNA is mandatory in order to investigate the possibility of inherited disease. In several areas, controversial opinions exist, depending on diversity in discipline, specific research area, experience in the field, and cultural and religious backgrounds. In particular, in vitro fertilization combined with pre-implantation genetic diagnosis is an area which attracts considerable emotion.

CONCLUSIONS

In order to avoid confusion in the families, explicit and common guidelines are needed for the identification, treatment and follow-up of individuals who have predisposing MEN or VHL mutations. Close collaboration between endocrinologists, oncologists, surgeons, pathologists, psychologists and geneticists is required in order to establish and verify such guidelines.

Fourth ventricular hemangioblastoma associated with pheochromocytoma and renal medullary fibroma

Intraventricular hemangioblastomas are exceptionally rare. Of the cases described in the literature, very few were associated with von Hippel-Lindau disease. We present a highly unusual case of a fourth ventricular hemangioblastoma associated with a pheochromocytoma and a renal medullary fibroma. This may represent a forme fruste of the von Hippel-Lindau complex. A workup for papilledema resulted in the discovery of this rare finding.