Treatment of hemangioblastomas in von Hippel-Lindau disease with linear accelerator-based radiosurgery

Stereotactic Radiosurgery for Cranial and Spinal Hemangioblastomas: A Single-Institution Retrospective Series

BACKGROUND AND OBJECTIVES

Stereotactic radiosurgery (SRS) has been an attractive treatment modality for both cranial and spinal hemangioblastomas, especially for multiple lesions commonly associated with von Hippel-Lindau (VHL) disease. This study aims to provide the largest long-term analysis of treatment efficacy and adverse effects of SRS for cranial and spinal hemangioblastomas at a single institution.

METHODS

We evaluated the clinical and radiological outcomes of patients with hemangioblastomas treated with CyberKnife SRS at our institute from 1998 to 2022. The follow-up data were available for 135 hemangioblastomas in 35 patients. Twenty-eight patients had 123 hemangioblastomas associated with VHL, and 7 had 12 sporadic hemangioblastomas. The median age was 36 years, and the median tumor volume accounted for 0.4 cc. The SRS was administered with the median single-fraction equivalent dose of 18 Gy to the 77% median isodose line.

RESULTS

At a median follow-up of 57 months (range: 3-260), only 20 (16.2%) of the VHL-associated and 1 (8.3%) sporadic hemangioblastomas progressed. The 5-year local tumor control rate was 91.3% for all hemangioblastomas, 91.7% among the sporadic lesions, and 92.9% in patients with VHL. SRS improved tumor-associated symptoms of 98 (74.8%) of 131 symptomatic hemangioblastomas, including headache, neck pain, dizziness, visual disturbances, dysesthesia, ataxia, motor impairment, seizures, and dysphagia. Two patients developed radiation necrosis (5.7%), and 1 of them required surgical resection.

CONCLUSION

SRS is a safe and effective treatment option for patients with hemangioblastomas in critical locations, such as the brainstem, cervicomedullary junction, and spinal cord, and in patients with multiple hemangioblastomas associated with VHL disease.

Stereotactic radiotherapy for spinal hemangioblastoma - disease control and volume analysis in long-term follow up

Background

This retrospective analysis evaluated the long-term outcome of spinal stereotactic body radiotherapy (SBRT) treatment for hemangioblastomas.

Materials and methods

Between 2010 and 2018, 5 patients with 18 Von-Hippel Lindau-related pial-based spinal hemangioblastomas were treated with fractionated SBRT. After precisely registering images of all relevant datasets, we delineated the gross tumor volume, spinal cord (including intramedullary cysts and/or syrinxes), and past radiotherapy regions. A sequential optimization algorithm was used for dose determinations, and patients received 25–26 Gy in five fractions or 24 Gy in three fractions. On-line image guidance, based on spinal bone structures, and two orthogonal radiographs were provided. The actuarial nidus control, surgery-free survival, cyst/syrinx changes, and progression-free survival were calculated with the Kaplan-Meier method. Toxicities were graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events v5.0.

Results

The median follow-up was 5 years after SBRT. Patients displayed one nidus progression, one need of neurosurgery, and two cyst/syrinx progressions directly connected to symptom worsening. No SBRT-related complications or acute adverse radiation-related events occurred. However, one asymptomatic radiological sign of myelopathy occurred two years after SBRT. All tumors regressed; the one-year equivalent tumor volume reduction was 0.2 mL and the median volume significantly decreased by 28% (p = 0.012). Tumor volume reductions were not correlated with the mean (p = 0.19) or maximum (p = 0.16) dose.

Conclusions

SBRT for pial-based spinal hemangioblastomas was an effective, safe, viable alternative to neurosurgery in asymptomatic patients. Escalating doses above the conventional dose-volume limits of spinal cord tolerance showed no additional benefit.

Linear accelerator stereotactic radiosurgery can modulate the clinical course of Hemangioblastoma: Case series and review of the literature

Hemangioblastomas (HB) are benign low grade vascular tumors most frequently occurring in the cerebellum, brain stem, and spinal cord. Often associated with Von Hippel Lindau disease (VHL), the lesions are often multifocal requiring complex resection and are difficult to control. Linear Accelerator (LINAC) Stereotactic Radiosurgery (SRS) has been demonstrated to provide additional tumor control. In this case series, we present our multi-center experience utilizing LINAC SRS in fourteen patients with 23 lesions. We observed a tumor control rate of 87% and found interval changes in the peritumoral enhancement to correlate with treatment outcome. In our study, SRS treatment was also well-tolerated in both cystic and noncystic patients with multifocal disease. Disease control was achieved in all but three patients post-resection and no longitudinal radiation-induced secondary malignancy was observed. SRS response correlated highly with lesion size and radiation dose. We conclude that LINAC SRS is safe and effective for patients with HB and should be considered in addition to surgery in asymptomatic, VHL patients, deep seated lesions and isolated lesions.

VON HIPPEL-LINDAU DISEASE: Update on Pathogenesis and Systemic Aspects

PURPOSE

To provide an update summarizing the biologic pathways governing von Hippel-Lindau (VHL) disease pathogenesis and to provide an overview of systemic manifestations as well as screening recommendations.

METHODS

A PubMed search of the English language literature was reviewed using the following search terms: von Hippel-Lindau, von Hippel-Lindau disease, and VHL. Of 6,696 publications, the most current and pertinent information related to the pathogenesis and systemic aspects of VHL disease were included in this review.

RESULTS

von Hippel-Lindau disease is one of the most frequently occurring multisystem familial cancer syndromes. The disease results from germline mutation in the VHL tumor suppressor gene on the short arm of chromosome 3. Mutation in the VHL gene affects multiple cellular processes including transcriptional regulation, extracellular matrix formation, apoptosis, and, in particular, the cellular adaptive response to hypoxia. As a result, there is widespread development of vascular tumors affecting the retina, brain, and spine, as well as a spectrum of benign and malignant tumors and/or cysts in visceral organs.

CONCLUSION

The ophthalmologist plays a key role in VHL disease diagnosis, as retinal hemangioblastoma is frequently the first disease manifestation. Screening guidelines for individuals with known VHL disease, and those at risk of VHL disease, help to ensure early detection of potentially vision-threatening and life-threatening disease.

Stereotactic radiosurgery for central nervous system hemangioblastoma in von Hippel-Lindau disease: A systematic review and meta-analysis

Von Hippel-Lindau (VHL) disease is a dominantly inherited disorder marked by multiorgan tumors, such as central nervous system benign hemangioblastomas (CHB). Stereotactic radiosurgery (SRS) has also been used to treat CHB for a long time. The purpose of this meta-analysis is to provide a long-term outcome of SRS for VHL-associated CHB by reviewing published studies. We completed a Pubmed/Embase/SCOPUS/Cochrane Library literature search to get eligible studies published from January 1990 to December 2019 about using SRS to treat VHL-associated CHB. 15 studies met eligibility for qualitative systematic review, of which nine studies were ultimately eligible for quantity meta-analysis of 5-year tumor control rates (TCR), representing 170 subjects with a total of 660 lesions. Gamma Knife was the most published SRS method for VHL-associated CHB. The pooled 5-year TCR across the nine studies was 0.919 (95 %CI: 0.881-0.957). The pooled 5-year TCR for only intracranial lesions across eight studies was 0.917 (95 %CI: 0.876-0.957). Individual patient data were extracted from 9 studies, representing 298 lesions of 70 subjects. Sex, tumor volume, radiosurgery methods, marginal doses, maximum doses, the number of tumors for radiosurgery, age at the time of radiosurgery, tumor locations were not proven to be associated with tumor progression. SRS offered a satisfactory 5-year tumor control of CHB for VHL patients. Despite the paucity of randomized control trials, SRS is recommended to patients with limited surgical alternatives. However, the long-term outcomes and underlying factors associated with tumor progression remain to be investigated.

Combined Microsurgery and Radiotherapy for Multiple Spinal Cord Hemangioblastomas with Holocord Syrinx in von Hippel-Lindau Disease: A Case Report

Spinal and cerebellar hemangioblastomas are common in von Hippel-Lindau disease (vHLD) and usually treated surgically. Multifocal presence and surgically not amenable locations are issues that require a combined microsurgical and radiosurgical approach to control complex cases. We would like to present the case of a 37-year-old male patient who was diagnosed vHLD with multiple spinal and one infratentorial hemangioblastomas and holocord syrinx formation of the whole spinal cord. Combined microsurgical approaches to two spinal lesions and the cerebellar lesion followed by external beam radiotherapy of the posterior fossa and the whole spinal axis stabilized tumor growth of the asymptomatic lesions, while no recurrent tumors were detected at the site of surgery. A clinical deterioration connected to early postoperative deficits stabilized to a moderate gait ataxia. The follow-up after radiotherapy covered 60 months. A combination of microsurgery and radiosurgery for the surgically not amenable lesions is an adequate treatment regimen to stabilize tumor growth and clinical symptoms of multifocal spinal hemangioblastomas in vHLD, though the therapy should be limited to symptomatic or growing lesions.

Long-term outcome of treatment of vertebral body hemangiomas with direct ethanol injection and short-segment stabilization

BACKGROUND

Vertebral body hemangiomas with myelopathy are difficult to manage.

OBJECTIVE

The objective of this study was to evaluate the role of intraoperative ethanol embolization, surgical decompression, and instrumented short-segment fusion in vertebral hemangioma (VH) with myelopathy and long-term outcome (>24 months).

CLINICAL MATERIALS AND METHODS

This prospective study included symptomatic VH with cord compression with myelopathy. Pathologic fractures and deformity or multilevel pathologies were excluded from the study. Surgery consisted of intraoperative bilateral pedicular absolute alcohol (<1% hydrated ethyl alcohol) injection, laminectomy, and cord decompression at the level of pathology followed by a short-segment instrumented fusion using pedicle screws.

RESULTS

The study included 33 patients (mean 26.9±13.2, range: 10-68 years, 18 females). The clinical features of the study were myelopathy in all patients (5 paraplegic), sphincter involvement (13), and mid back or lower back pain (7). The preoperative American Spinal Injury Association (ASIA) scores were A (7), B (11), C (6), D (8), and E (1). Majority of the patients had single vertebral involvement (30) and three patients had multiple-level involvement. Six patients underwent surgery earlier (one underwent alcohol embolization). The mean surgical time was 124±39 minutes, and the average blood loss was 274±80 cc. The mean amount of absolute alcohol injected was 14.6±5.7 cc (two patients required 20 and 25 cc). Immediate embolization was achieved in all patients, allowing laminectomy and easy removal of soft-tissue hemangioma. Post surgery, one patient had transient deterioration, and the condition of the rest of the patients improved (sphincters improved in nine patients) at a follow-up ranging 28-103 months (mean 47.6±22.3). Follow-up ASIA scores were E (26), D (4), B (2), and C (1). All patients showed evidence of bone sclerosis and relief of cord compression on follow-up imaging.

CONCLUSIONS

This is the largest study in literature showing excellent improvement, low reoperation rates after ethanol embolization, and short-segment fixation.

Staged multi-modality treatment approaches for giant cerebellopontine angle hemangioblastomas

Giant hemangioblastomas (HBs) located in the cerebellopontine angle (CPA) present rare, high risk neurosurgical challenges. En bloc resection has been traditionally recommended for HBs, however this approach may pose unacceptable risk with giant tumors. Alternative treatment strategies have not been well described and the relevant literature is scant. This case review includes an illustrative patient with a giant, symptomatic CPA HB. It was felt that the neurovascular and tumor attributes were favorable for a multi-modality treatment strategy rather than circumferential dissection to remove this formidable tumor. A staged approach consisting of preoperative HB devascularization, debulking and piecemeal resection followed by radiosurgery for a small residuum produced an excellent clinical outcome. Variations of this unconventional multi-modality strategy may reduce the perioperative morbidity of carefully selected patients with giant CPA HBs. A thorough literature review is provided.

Stereotactic radiosurgery for central nervous system hemangioblastoma: systematic review and meta-analysis

Hemangioblastomas are rare, benign, vascular tumors of the central nervous system (CNS), often associated with von-hippel lindau (VHL) disease. Current therapeutic options include microsurgical resection or stereotactic radiosurgery (SRS). With no randomized controlled studies and minimal data beyond single-institution reviews, the optimal management approach for patients with CNS hemangioblastomas is unclear. We completed a Pubmed/SCOPUS literature search from January 1990 to January 2017 for eligible studies on SRS for CNS hemangioblastomas. Relevant articles were identified and reviewed in accordance to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. 26 studies met eligibility criteria for qualitative synthesis, representing 596 subjects and 1535 tumors. The Gamma Knife was the most published SRS method for CNS hemangioblastomas. After critical study appraisal for intra-study bias, 14 studies were used for quantitative meta-analysis of 5-year progression free survival (PFS). The pooled 5-year PFS across all eligible studies was 88.4%. No difference was observed between spine versus intracranial studies. Individual patient data (IPD) was extracted from 14 studies, representing 322 tumors. Univariate analysis of IPD revealed that VHL patients were younger, and had smaller tumors compared to those with sporadic disease. Adverse events were associated with increasing marginal dose, independent of tumor volume. VHL status, sex, radiosurgical method, tumor location, and tumor volume were not found to be significantly associated with tumor progression. Multiple studies show excellent tumor control at 5-year follow up, however, the long-term efficacy of SRS for CNS hemangioblastomas still needs to be investigated, and the studies exploring the role of SRS for early treatment of asymptomatic lesions is wanting.

Review of stereotactic radiosurgery for intradural spine tumors

Stereotactic radiosurgery (SRS) has become an increasingly popular treatment modality for spinal tumors due to its noninvasive and targeted approach. Whether SRS has the promise of relieving pretreatment symptoms and providing local tumor control for patients with intradural spine tumors is still debated. This review explores the current literature on SRS treatment for both metastatic and benign intradural tumors, with a focus on differential use for intramedullary and intradural extramedullary neoplasms. Although mortality rates from underlying malignant disease remain high, SRS may benefit patients with spinal metastatic lesions. Benign tumors have shown a promising response to SRS therapy with low rates of complications. Larger studies are necessary to determine the indications and outcome profile of SRS for intradural spinal neoplasms.

Development of Database and Genomic Medicine for von Hippel-Lindau Disease in Japan

von Hippel-Lindau (VHL) disease is a hereditary tumor disease in which tumors develop in multiple organs, not only as hemangioblastomas (HBs) in the central nervous system, but also as kidney tumors, pheochromocytomas, and so on. Much about the epidemiology of VHL disease remained unknown until fairly recently in Japan, leading to calls for the establishment of a VHL disease epidemiological database in Japanese. To elucidate its epidemiology in Japan, the Japanese Ministry of Health, Labour and Welfare created the VHL Disease Study Group, which was put in charge of carrying out a nationwide epidemiological survey. The survey found close to 400 Japanese VHL disease patients throughout the country. Based on those results, the VHL Disease Study Group created the VHL Disease Treatment Guideline and also a severity classification. It is thought that the prognosis of VHL disease patients can be improved by performing genetic diagnosis and careful follow-up. Accordingly, the University of Tokyo Hospital put in place an in-hospital system for implementing genomic medicine for VHL disease based on genetic diagnosis. For that system, it was especially important to establish (I) accurate genetic diagnostic techniques, (II) genetic counseling capabilities for the patients and their families, and (III) a system of cooperation among multiple departments, including urology departments, and so on. Further elucidation of the epidemiology and the development of genomic medicine are needed to improve the treatment results of VHL disease in Japan.

von Hippel-Lindau Disease: Review of Genetics and Imaging

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

Supratentorial haemangioblastoma without von Hippel-Lindau syndrome in an adult: A rare tumor with review of literature

Supratentorial hemangioblastomas (HBLs) are rare, benign vascular tumors of the central nervous system neoplasms. Very scarce literature is available regarding supratentorial HBL without von Hippel–Lindau (VHL) syndrome in an adult. We reviewed the literature and PubMed advanced search showed only a few results of supratentorial HBL without VHL syndrome. We reported a rare case of cystic supratentorial HBL in 39-year-old male affecting the parietal lobe without VHL syndrome. Supratentorial HBL is a rare tumor and supratentorial HBL without VHL syndrome are even rarer. Being a rare entity, not much clinical data is currently available regarding supratentorial HBLs, thus necessitating the need for further reporting and review of such cases.

Intramedullary hemangioblastomas: surgical results in 16 patients

OBJECT

Hemangioblastomas are rare, benign, highly vascularized tumors that can be found throughout the neuraxis but are mainly located in the cerebellum and in the spinal cord. Spinal hemangioblastomas can present with motor and sensory deficits, whose severity varies according to the size and location of the tumor. Resection is the best treatment option to avoid neurological deterioration. The authors report surgical results in the treatment of intramedullary hemangioblastomas and discuss the technical nuances important to achieving total resection without adding new deficits.

METHODS

A consecutive series of patients with intramedullary hemangioblastomas operated on between 2000 and 2014 by the senior author (H.T.) is presented. The functional scale proposed by McCormick was used to evaluate the patients' neurological status before and after surgery.

RESULTS

Sixteen patients were included in the study and underwent 17 surgeries. Follow-up was at least 6 months. Age at presentation varied from 13 to 58 years (mean 33.8 years). Ten patients (62.5%) were males and 6 patients (37.5%) were females. Seven (43.75%) of the 16 patients had associated von Hippel—Lindau syndrome, with hemangioblastomas also presenting in other locations. Three patients had multiple tumors in the same segment in the spinal cord, and 10 patients (62.5%) presented with cysts. According to the site of presentation, 11 tumors (68.75%) were localized at the cervical region (including the cervicomedullary junction) and 5 tumors (31.25%) at the thoracic level. Total resection was achieved in all cases, evidenced by postoperative MRI. Four patients had some functional worsening immediately after surgery. After 6 months, 1 patient had functional worsening compared with preoperative status, and 2 patients had clinical improvement. The majority of the patients remained clinically stable postoperatively.

CONCLUSIONS

Adequate knowledge of anatomy and the correct use of microsurgical techniques allowed total resection of these tumors, with minimal morbidity and maximum functional recovery. Outcome seems to be directly related to the neurological status before surgery.

The role of stereotactic radiosurgery in the treatment of intramedullary spinal cord neoplasms: a systematic literature review

Advances in imaging technology and microsurgical techniques have made microsurgical resection the treatment of choice in cases of symptomatic intramedullary tumors. The use of stereotactic radiosurgery (SRS) for spinal tumors is a recent development, and its application to intramedullary lesions is debated. We conducted a literature search through PubMed's MeSH system, compiling information regarding intramedullary neoplasms treated by SRS. We compiled histology, tumor location and size, treatment modality, radiation dose, fractionation, radiation-induced complications, follow-up, and survival. Ten papers reporting on 52 patients with 70 tumors were identified. Metastatic lesions accounted for 33%, while 67% were primary ones. Tumor location was predominantly cervical (53%), followed by thoracic (33%). Mean volume was 0.55 cm(3) (95% confidence interval (CI), 0.26-0.83). Preferred treatment modality was CyberKnife® (87%), followed by Novalis® (7%) and linear particle accelerator (LINAC) (6%). Mean radiation dose was 22.14 Gy (95% CI, 20.75-23.53), with mean fractionation of 4 (95% CI, 3-5). Three hemangioblastomas showed cyst enlargement. Symptom improvement or stabilization was seen in all but two cases. Radionecrotic spots adjacent to treated areas were seen at autopsy in four lesions, without clinical manifestations. Overall, clinical and radiological outcomes were favorable. Although surgery remains the treatment of choice for symptomatic intramedullary lesions, SRS can be a safe and effective option in selected cases. While this review suggests the overall safety and efficacy of SRS in the management of intramedullary tumors, future studies need randomized, homogeneous patient populations followed over a longer period to provide more robust evidence in its favor.

Stereotactic radiosurgery for intracranial hemangioblastomas: a retrospective international outcome study

OBJECT

The purpose of this study was to evaluate the role of stereotactic radiosurgery (SRS) in the management of intracranial hemangioblastomas.

METHODS

Six participating centers of the North American Gamma Knife Consortium and 13 Japanese Gamma Knife centers identified 186 patients with 517 hemangioblastomas who underwent SRS. Eighty patients had 335 hemangioblastomas associated with von Hippel–Lindau disease (VHL) and 106 patients had 182 sporadic hemangioblastomas. The median target volume was 0.2 cm3 (median diameter 7 mm) in patients with VHL and 0.7 cm3 (median diameter 11 mm) in those with sporadic hemangioblastoma. The median margin dose was 18 Gy in VHL patients and 15 Gy in those with sporadic hemangioblastomas.

RESULTS

At a median of 5 years (range 0.5–18 years) after treatment, 20 patients had died of intracranial disease progression and 9 patients had died of other causes. The overall survival after SRS was 94% at 3 years, 90% at 5 years, and 74% at 10 years. Factors associated with longer survival included younger age, absence of neurological symptoms, fewer tumors, and higher Karnofsky Performance Status. Thirty-three (41%) of the 80 patients with VHL developed new tumors and 17 (16%) of the106 patients with sporadic hemangioblastoma had recurrences of residual tumor from the original tumor. The 5-year rate of developing a new tumor was 43% for VHL patients, and the 5-year rate of developing a recurrence of residual tumor from the original tumor was 24% for sporadic hemangioblastoma patients. Factors associated with a reduced risk of developing a new tumor or recurrences of residual tumor from the original tumor included younger age, fewer tumors, and sporadic rather than VHL-associated hemangioblastomas. The local tumor control rate for treated tumors was 92% at 3 years, 89% at 5 years, and 79% at 10 years. Factors associated with an improved local tumor control rate included VHL-associated hemangioblastoma, solid tumor, smaller tumor volume, and higher margin dose. Thirteen patients (7%) developed adverse radiation effects (ARE) after SRS, and one of these patients died due to ARE.

CONCLUSIONS

When either sporadic or VHL-associated tumors were observed to grow on serial imaging studies, SRS provided tumor control in 79%–92% of tumors.

Von Hippel-Lindau disease

von Hippel-Lindau (VHL) disease is an inheritable condition with an incidence of 1 in 36000 live births. Individuals with VHL develop benign and malignant tumors including retinal and central nervous system hemangioblastomas, clear cell renal cell carcinomas (RCC), pheochromocytomas, pancreatic neuroendocrine tumors and endolymphatic sac tumors (ELSTs). VHL is caused by germline loss of function of the VHL gene on one allele at chromosome 3p25-26. A somatic "second hit" event leads to the loss of the other allele and tumor formation. Loss of VHL function in cells leads to increased expression and stabilization of hypoxia inducible factor (HIF). VHL protein/HIF pathway has been implicated in tumorigenesis for hemangioblastomas, RCC and other VHL tumors. Clinical examination, imaging, and genetic testing for VHL mutations confirm VHL disease. Management of VHL disease largely consists of surgical resection of symptomatic tumors (hemangioblastomas), tumors prone to metastasize (RCC larger than 3cm), or tumors causing hormonal symptoms (pheochromocytomas). Despite advances in early diagnosis and management of VHL disease, life expectancy for VHL patients remains low at 40-52 years. Secondary effects from VHL manifestations are mitigated by routine surveillance and early detection. In this chapter, we summarize the current state of knowledge in VHL disease.

The clinical outcome of intracranial hemangioblastomas treated with linac-based stereotactic radiosurgery and radiotherapy

Recent publications have reported stereotactic radiosurgery as an effective and safe treatment for intracranial hemangioblastomas. However, because of the low incidence of these particular tumors, reports on large patient number studies have not yet been available. The objective of this study was to analyze the clinical results of 14 patients with 56 intracranial hemangioblastomas treated with linear accelerator (linac)-based stereotactic radiosurgery (SRS) and radiotherapy (SRT) in the same institute. The median age of patients was 41 years (range, 28-73 years). Nine of the patients (64%) had von Hippel-Lindau disease. A total of 39 lesions (70%) were treated with CyberKnife (CK), and 17 lesions (30%) were treated with X-Knife. The median pretreatment volume was 0.26 cm(3) (range, 0.026-20.4 cm(3)). The median marginal dose was 20 Gy (range, 10-32 Gy) in 1 fraction (range, 1-10 fractions). The median follow-up time was 24 months (range, 11-89 months). At the last follow-up, 47 tumors (84%) were stable, 7 (13%) decreased and 2 (4%) increased. The 1-, 2- and 6-year local control rates were 98%, 88% and 73%, respectively. No radiation complications were observed in this study. There was a trend toward local failure only in cystic tumors, but this trend was not found to be statistically significant. SRS/SRT achieved a high local control rate in intracranial hemangioblastomas without radiation-induced complications.

Operative management of brainstem hemangioblastomas

Brainstem hemangioblastomas are technically challenging lesions. The authors retrospectively analyzed their experience in 24 patients with brainstem hemangioblastomas to evaluate the management strategies used over time and the results of microsurgical treatment. All patients were operated on between 2007 and 2012. The patients received postoperative follow-up by neuroradiological and neurological examinations. The maximum diameter of the tumors ranged from 2.0 to 4.5 cm (mean 3.6 cm). Gross total resection was achieved in 24 patients (100%). Two patients (8%) had new neurological deficits or worsening of pre-existing deficits. One patient (4%) died because of brain stem dysfunction after the operation. Radical en bloc surgical resection of brainstem hemangioblastomas in symptomatic patients is a safe and effective primary treatment. Preoperative embolization is not necessary. It is very important and necessary to differentiate and dissect precisely at the interface of the tumor surface and the brainstem with a meticulous microsurgical technique until the tumor is removed en bloc. The preoperative neurological status of the patient predicts the postoperative functional outcome. Asymptomatic patients with hemangioblastoma may be followed clinically with MRI surveillance at regular intervals.

Supratentorial hemangioblastomas: three case reports and review of the literature

Hemangioblastoma (HBL) within the central nervous system is a benign vascular neoplasm that usually occurs in the cerebellum. Supratentorial occurrence of HBL is an extremely rare event. Till date, approximately 129 cases of supratentorial HBL have been reported in the literature. Here, we present three new cases of supratentorial hemangioblatomas, one of which was found to have the lesions in a unique location of the choroidal fissure. The clinical, histopathological, and neuroradiological characteristics, as well as management of this rare disease are discussed with a review of the pertinent literature.

Management of von Hippel-Lindau disease-associated CNS lesions

Patients with von Hippel-Lindau disease (VHL) often harbor significant disease burden within the CNS, specifically craniospinal-axis hemangioblastomas and endolymphatic sac tumors (ELSTs). The majority (60-80%) of patients with VHL harbor hemangioblastomas, and 10-15% will develop ELSTs. Advances in the understanding of the natural history and outcomes associated with the surgical management of VHL-associated tumors have led to improved management of patients with VHL. Optimizing indications for surgical intervention and refining of surgical techniques for these lesions can reduce patient morbidity associated with the management of this syndrome. In this article, we review the various aspects of perioperative management of patients with VHL, surgical indications and general operative principles for the management of hemangioblastomas and ELSTs, and outcomes associated with the surgical treatment of these tumors.

Neurosurgical considerations in von Hippel-Lindau disease

Von Hippel-Lindau disease is an inherited syndrome predisposing to a variety of benign and malignant neoplasms of the central nervous system and viscera that requires comprehensive screening and follow-up of individuals and their families. As such, it is important for the neurosurgeon to be aware of its clinical features and management issues. In this article we review the clinical aspects, management and surveillance of von Hippel-Lindau disease for neurosurgical practice.

Clinical and surgical features of lower brain stem hemangioblastomas in von Hippel-Lindau disease

BACKGROUND

In the context of von Hippel-Lindau disease (VHL), the medulla oblongata is a relatively frequent site of growth of hemangioblastomas, posing related clinical and surgical difficulties. Their management requires a close correlation between clinical evolution and morphological surveillance. In order to describe their clinical and surgical features, we reviewed our experience in the treatment of these lesions.

METHODS

Between 2001 and 2009, 14 patients (9 female and 5 male, mean age 34 years) underwent removal of 15 lower brain stem hemangioblastomas. Based on the review of the clinical records and outpatient long-term follow-up visits, their clinical course was analyzed. Functional evaluation was measured with the Karnofsky Performance Scale (KPS) on admission, at discharge and at the last follow-up. The mean follow-up period was 30.8 months (range 4-99).

RESULTS

All the operated hemangioblastomas were located in the dorsal medulla oblongata, in the context of multiple lesions, cerebellar and/or spinal. In ten patients hemangioblastomas were located in a median position at the obex area; in four cases a lateral location was observed. Cystic component was absent in two cases. Clinical onset preceded surgery by a mean of 8.5 months. Preoperatively three patients showed a KPS lower than 80, ten patients between 80 and 90, and one patient scored 100 (asymptomatic). There was no surgical mortality. Nine out of 14 patients showed a temporary surgical morbidity. One patient required a tracheostomy. At follow-up ten patients scored a KPS better than before the operation, while the other four patients remained stable. Permanent morbidity was observed in three patients.

CONCLUSIONS

Lower brain stem hemangioblastomas in the context of VHL show an often gradual onset of signs and symptoms except for patients who develop an obstructive hydrocephalus. Although transient surgical complications are possible, surgery provides favorable long-term results.

Von Hippel Lindau syndrome

Von Hippel-Lindau syndrome (VHLS) is an autosomal dominant familial cancer syndrome arising from germ-line inactivation of the VHL gene on the short arm of chromosome 3. VHLS manifests in a myriad of hyper-vascular tumors of both benign and malignant nature. Incidence of VHLS is roughly 1 in 36,000 live births and has over 90% penetrance by the age of 65. Improved understanding of the natural history and biology of VHLS has led to the introduction of screening protocols, early interventions and improved treatments, all of which resulted in a substantially improved prognosis for this disease. Further details regardingvariegated molecular pathways and mechanisms ofVHLS are emerging with the subsequent advent of novel treatment protocols that are currently in clinical trials.

Prospective evaluation of radiosurgery for hemangioblastomas in von Hippel-Lindau disease

To determine the effectiveness of stereotactic radiosurgery (SRS) treatment to central nervous system (CNS) hemangioblastomas in von Hippel-Lindau disease (VHL), we analyzed long-term results in VHL patients treated with SRS. Patients were enrolled in a prospective VHL natural history study, undergoing SRS treatment of CNS hemangioblastomas. Treatment regimens, serial clinical evaluations, and longitudinal imaging data were analyzed. Twenty VHL patients (10 males and 10 females) underwent SRS treatment of 44 CNS hemangioblastomas (39 cerebellar and 5 brainstem). Mean (+/-SD) age at treatment was 37.5 +/- 12.0 years (range: 13-67). Mean follow-up was 8.5 +/- 3.2 years (range: 3.0-17.6 years). All patients were alive at last follow-up. Mean treated tumor volume was 0.5 +/- 0.7 cm(3) (range: 0.01-3.6 cm(3)). Mean prescription dose was 18.9 Gy (range: 12-24 Gy) at the tumor margin. Local control rate at 2, 5, 10, and 15 years after SRS treatment was 91%, 83%, 61%, and 51%, respectively. Univariate analysis did not identify variables associated (P > .05) with worse tumor control at last follow-up. Thirty-three percent of SRS-treated small (<1.0 cm diameter), asymptomatic tumors progressed over a long-term follow-up. There were no long-term adverse radiation effects. Although SRS treatment of hemangioblastomas in VHL has a low risk for adverse radiation effects, it is associated with diminishing control over a long-term follow-up. These results indicate that SRS should not be used to prophylactically treat asymptomatic tumors and should be reserved for the treatment of tumors that are not surgically resectable.

Stereotactic radiosurgical treatment of cranial and spinal hemangioblastomas

OBJECTIVE

Stereotactic radiosurgery has been used for nearly 2 decades to treat hemangioblastomas, particularly those that are in surgically inaccessible locations or that are multiple, as is common in von Hippel-Lindau disease. There is a paucity of long-term published radiosurgical treatment outcomes, particularly for spinal lesions, in a large patient population. The purpose of this study was to provide a long-term retrospective evaluation of radiosurgical hemangioblastoma treatment effectiveness, with a special emphasis on the relatively recent use of frameless, image-guided radiosurgery in the treatment of spinal lesions.

METHODS

From 1991 to 2007, 92 hemangioblastomas in 31 patients, 26 with von Hippel-Lindau disease, were treated with radiosurgery (27 tumors treated with frame-based linear accelerator radiosurgery, and 67 tumors were treated with CyberKnife radiosurgery). The mean patient age was 41 years (range, 18-81 years). The radiation dose to the tumor periphery averaged 23.4 Gy (range, 12-40 Gy). The mean tumor volume was 1.8 cm (range, 0.058-65.4 cm). Tumor response was evaluated in serial, contrast-enhanced, computed tomographic, and magnetic resonance imaging scans.

RESULTS

Clinical and radiographic follow-up data were available for 82 hemangioblastoma tumors. Only 13 (16%) of the treated hemangioblastomas progressed, whereas 18 tumors (22%) showed radiographic regression, and 51 tumors (62%) remained unchanged in size. With median follow-up of 69 months (range, 5-164 months), the actuarial local control rates at 36 and 60 months were 85% and 82%, respectively. Radiosurgery improved lesion-associated symptoms in 36 of 41 tumors. During the follow-up period, 9 patients died of causes unrelated to the progression of their treated hemangioblastomas, and 5 patients developed radiation necrosis.

CONCLUSION

Stereotactic radiosurgery is safe and effective in the treatment of hemangioblastomas and is an attractive alternative to surgery for patients, including those with von Hippel-Lindau disease.

Abordagem cirúrgica dos hemangioblastomas intramedulares

OBJETIVO: descrever uma experiência e as técnicas para abordagem destas lesões com ênfase nos aspectos microcirúrgicos. MÉTODOS: foram relatados nove casos consecutivos de pacientes submetidos à ressecção de lesões intramedulares operados entre 2000 e 2008. A escala funcional de McCormick foi usada para avaliar o status funcional dos pacientes RESULTADOS: a idade dos pacientes variou de 13 a 45 anos (média de 27,1 anos). Quatro (44,4%) pacientes eram homens e cinco (55,5%), mulheres. Dois pacientes tinham a doença de von Hippel-Lindau, com outros hemangioblastomas associados. Conforme a localização, sete (77,7%) pacientes tinham lesões na região cervical (dois deles com tumores na transição crânio-cervical) e dois (22,2%) tinham lesões na região torácica. Todos os pacientes tiveram ressecção total das lesões, sendo que três apresentaram leve piora clínica no pós-operatório imediato. Após seis meses do procedimento cirúrgico, dois pacientes apresentaram melhora clínica, enquanto sete mantinham-se funcionalmente iguais ao período pré-operatório. CONCLUSÕES: o conhecimento anatômico e de técnicas microcirúrgicas adequadas permite a ressecação total destas lesões sem agregar morbidade adicional.

A vitronectin M381T polymorphism increases risk of hemangioblastoma in patients with VHL gene defect

Hemangioblastomas, highly vascular tumors, occur sporadically or associated with von Hippel-Lindau (VHL) disease. Diverse mutations in the VHL gene inactivate the VHL protein and constitute the molecular etiology of the disease. Changes in VHL gene were analyzed in patients with multiplex ligation-dependent probe amplification and single-strand conformation polymorphism analyses. We report here that other angiogenesis-related changes in vitronectin were identified with 2D electrophoresis of plasma samples and restriction fragment length polymorphisms. Our findings revealed that most patients (80.0%) with a familial VHL deletion carried the threonine (T) allele at vitronectin codon 381. Adults simultaneously carrying a VHL defect and the T allele were 5.0-fold more likely to be affected by VHL disease than were methionine/methionine (M/M) homozygotes carrying a VHL defect. Patients with sporadic hemangioblastoma, C-terminally truncated VHL protein or a large deletion in the VHL gene, and the T allele were 18.0-fold more likely to develop recurrent disease. Taken together, individuals with mutated VHL are more likely to be affected by familial or recurrent sporadic hemangioblastoma when carrying the M/T or T/T genotype at codon 381 of vitronectin.

Solid haemangioblastomas of the CNS: a review of 17 consecutive cases

A retrospective study on solid central nervous system haemangioblastomas was performed to characterize clinical features, treatment strategies and outcome in these rare lesions. Between 1993 and 2006 23, solid haemangioblastomas were surgically removed in 17 patients. Eight lesions were located within pons Varolii and medulla oblongata, six within the cerebellar hemispheres and three in the cerebellopontine angle. Three haemangioblastomas were located supratentorially and three within the spinal cord. All patients except two underwent pre-operative magnetic resonance imaging (MRI). Post-operative digital subtraction angiography and/or MRI was performed in all surviving patients. Except for spinal cord lesions, rather unsystematic clinical symptoms were observed. Twenty-two tumours could be resected completely. Two patients with brainstem lesions died within 10 weeks after surgery from infectious complications. Persistent new neurological deficits occurred in two patients. Three patients underwent radiosurgery prior to or following the surgical procedure. Solid haemangioblastomas represent a surgical challenge due to their arteriovenous malformation-like vascularisation and their frequent location in eloquent areas. Surgery is the therapy of choice. Circumferential dissection with devascularization and en bloc removal yields good functional results. A location within the brainstem carries the most unfavourable prognosis.

SPINAL DEFORMITY

OBJECTIVE

In this literature review, the authors analyze data from previously published studies that evaluated neutral upright spinal alignment (NUSA) from the occiput to the pelvis in asymptomatic individuals. Based on the data for NUSA in asymptomatic volunteers, a new classification is proposed for spinal deformity.

METHODS

A review of the English literature was conducted to identify studies evaluating NUSA from the occiput to the pelvis in asymptomatic juvenile, adolescent, adult, and geriatric volunteers. From the literature review, 17 angles and displacements were selected to depict neutral upright coronal and axial spinal alignment, and 21 angles and displacements were selected to depict neutral upright sagittal spinal alignment. Pooled estimates of the mean and variance were calculated for the angles and displacements from the articles that met inclusion criteria. A new classification of spinal deformity was then developed based on age-dependent NUSA; spinal abnormality; deformity curve location, pattern, magnitude, and flexibility; and global spinal alignment.

RESULTS

Despite a wide variation in the regional curves from the occiput to the pelvis in asymptomatic volunteers, global spinal alignment is maintained in a narrow range for preservation of horizontal gaze and balance of the spine over the pelvis and femoral heads.

CONCLUSION

A new classification of spinal deformity is proposed that provides a structure for defining deformity of all patient ages and spinal abnormalities.

Surgical management of cerebellar hemangioblastomas in patients with von Hippel–Lindau disease

Object

Despite the frequency of cerebellar hemangioblastomas in von Hippel–Lindau (VHL) disease, their optimum contemporary management has not been defined, and is made complex because of the multiple, progressive, and protean nature of the tumors found in patients with this disorder. To examine modern management and outcomes of cerebellar hemangioblastomas in VHL disease, the authors reviewed findings in patients with this disease who underwent resection of cerebellar hemangioblastomas.

Methods

Consecutive patients with VHL disease who underwent surgery for cerebellar hemangioblastoma(s) at the National Institutes of Health were included. Eighty consecutive patients (44 female and 36 male patients) underwent 126 operations for removal of 164 cerebellar hemangioblastomas (age at surgery 37.8 ± 10.3 years, follow-up duration 96.0 ± 60.3 months). Serial clinical examinations, imaging studies, and operative records were analyzed.

Results

Symptoms and signs included headache (94 operations; 75%), ataxia (55%), dysmetria (29%), and hydrocephalus (28%). Although the primary objective of surgery was resection of the hemangioblastoma considered responsible for symptoms (136 of the hemangioblastomas [83%]), 28 additional hemangioblastomas (17%) were removed during the same surgeries. Tumors associated with symptoms were larger (diameter 1.8 ± 1.9 cm; volume 2.8 ± 3.4 cm3; p < 0.05) and more likely to be associated with peritumoral edema or peritumoral cysts (100% associated with edema and/or cyst; p < 0.05) than asymptomatic tumors (diameter 1.1 ± 0.9 cm; volume 0.7 ± 0.4 cm3; 18%). More tumors were located in the posterior (74%) compared with the anterior (26%) half of the cerebellum (p < 0.05). Three months after resection, symptom improvement/stabilization had occurred following 124 of the operations (98%). Preoperative hydrocephalus resolved after tumor removal in 33 cases (94%) and did not require cerebrospinal fluid diversion. Long-term imaging follow-up (61.5 ± 15.0 months) revealed no recurrences.

Conclusions

Symptoms and signs caused by cerebellar hemangioblastomas in VHL disease are associated with edema and peritumoral cyst formation/propagation and are treated safely and effectively with resection. Cerebrospinal fluid diversion is rarely necessary after complete tumor removal in patients with preoperative hydrocephalus. Cerebellar hemangioblastomas are preferentially distributed in the posterior half of the cerebellum, as they are in the brainstem and spinal cord. Tumor recurrence is avoided by meticulous extracapsular resection.

Gamma knife radiosurgery for intracranial haemangioblastomas

BACKGROUND

The results of gamma knife radiosurgery for haemangioblastomas were retrospectively studied to assess the efficacy for tumour growth control and clarify the clinical indications for gamma knife radiosurgery in these tumours.

METHODS

The medical records of 22 patients with 67 tumours, 12 men and 10 women aged 20-73 years (mean 51.9 years), who underwent gamma knife radiosurgery for haemangioblastomas between January 1993 and January 2006, were retrospectively reviewed. Ten patients with 54 lesions had von Hippel-Lindau disease. The mean tumour volume was 1.69 cm(3) (range 0.0097-16.4 cm(3)). Nineteen patients had undergone 1-4 open surgery procedures (mean 1.5) before gamma knife radiosurgery. Tumours without a cystic component, (the solid type), were found in 54 lesions and tumours associated with cyst, (the mural nodule with cyst type), in 13 lesions. The marginal dose was 8-30 Gy (mean 14.0 Gy).

FINDINGS

Follow-up magnetic resonance (MR) imaging was performed at 9-146 months (mean 63 months). The control rate for tumour growth was 83.6%. The only factor affecting tumour growth control was the presence of a cystic component at the time of gamma knife radiosurgery in both univariate and multivariate analysis. No complication such as radiation-induced peritumoural oedema or radiation necrosis occurred.

CONCLUSION

The presence of cystic components at the time of gamma knife radiosurgery was the only factor significantly correlated with unfavourable tumour growth control by gamma knife radiosurgery for haemangioblastomas. Gamma knife radiosurgery is effective for solid type tumours, even if the marginal dose is relatively low. Surgical removal is recommended for mural nodule with cyst type tumours, when possible.

Role of fractionated external beam radiotherapy in hemangioblastoma of the central nervous system

PURPOSE

To assess the clinical outcomes and toxicity in patients receiving fractionated external beam radiotherapy (EBRT) for hemangioblastoma of the central nervous system, treated at two Canadian radiation oncology institutions.

METHODS AND MATERIALS

Between January 1980 and December 2004, the data of all patients receiving EBRT for central nervous system hemangioblastoma were retrospectively reviewed. The patient, tumor, and treatment characteristics were collected and overall survival, disease-free survival, and EBRT-related toxicities assessed.

RESULTS

A total of 18 cases, 5 associated with von Hippel-Lindau disease (VHL) and 13 sporadic (non-VHL), with a total 31 lesions, were documented. These were located in the cerebellum in 20 and spinal cord in 8 patients. EBRT was delivered for recurrence in 12, adjuvantly for residual disease in 4, and definitively in 2. The EBRT schedules ranged from 50.0 to 55.8 Gy in 1.8-2.0-Gy daily fractions (n = 17), typically with parallel-opposed fields to the cerebellar target volumes and direct posterior fields for spinal disease. At a median follow-up of 5.1 years (range, 0.1-14.5), the 5-year OS rate was 69% (95% confidence interval [CI], 50-96%), decreasing to 30% (95% CI, 10-87%) at 10 years. The disease-free survival rate at 5 and 10 years was 57% (95% CI, 37-87%) and 30% (95% CI, 11-83%), respectively. The outcomes differed according to VHL status. The 5-year OS rate was 100% for those with VHL compared with 55% (95% CI, 32-95%) for those with non-VHL disease (log-rank p = 0.003), and the 5-year disease-free survival rate was 80% (95% CI, 52-100%) with VHL compared with 48% (95% CI, 26-89%) without (log-rank p = 0.036).

CONCLUSIONS

Fractionated EBRT has a role in the management of extensive intracranial and/or spinal cord disease, the adjuvant treatment of residual postoperative disease, and the treatment of recurrence. More favorable outcomes were reported for VHL-associated lesions than for sporadic cases.

Safety of radiosurgery applied to conditions with abnormal tumor suppressor genes

OBJECTIVE

To assess the risk of radiosurgery inducing malignancy in neurofibromatosis-2 (NF2) and von Hippel-Lindau disease.

METHODS

A retrospective cohort study of 118 NF2 and 19 von Hippel-Lindau disease patients, totalling 906 and 62 patient-years of follow-up data, respectively.

RESULTS

Two cases of intracranial malignancy were identified, both of which occurred in NF2 patients. One of these was thought to have arisen before the radiosurgery; the other was a glioblastoma diagnosed 3 years after radiosurgery.

CONCLUSION

Because gliomas may occur in as many as 4% of NF2 patients, this may not represent an increased risk. We continue to offer radiosurgery treatment to selected NF2 and von Hippel-Lindau disease patients and consider that the late risk of malignancy arising after irradiation must be put in the context of the condition being treated, the treatment options available to these individuals, and their life expectancy.

Pituitary stalk hemangioblastoma: The fourth case report and review of the literature

Supratentorial hemangioblastomas (HBL) have been rarely described in the literature. Herein we report the fourth case of pituitary stalk HBL diagnosed concurrently with cerebellar HBLs in a 51-year-old woman with von Hippel-Lindau disease. Complete resection of the lesion was achieved using left frontopterional craniotomy and no recurrence was observed after 8 years of follow-up. The clinical presentation, radiological features, pathological findings, and the management of this particular case are discussed in the light of the available literature. To our knowledge, this case is the only pituitary stalk HBL with total resection, and a long follow-up fully documented.

Surgical treatment of hemangioblastomas of the central nervous system in pediatric patients

OBJECTIVE

Hemangioblastomas are histologically benign lesions that occur sporadically or as a manifestation of von Hippel-Lindau disease (VHL). The treatment strategy of these neoplasms is complicated by their unpredictable growth patterns and the often irreversible neurological deficits they may cause. This study aims to outline the neurosurgical treatment options and to address the ongoing debate of surgical timing in pediatric patients with VHL.

PATIENTS AND METHODS

Thirteen consecutive pediatric patients (mean age 15.1 years) who were surgically treated for intracranial (n=8) or spinal hemangioblastomas (n=5) were included in this study (range of clinical follow up 12-86 months). Ten patients were affected by von Hippel-Lindau and three were with sporadic tumors. Serial examinations, preoperative MRI studies, and operative findings were reviewed.

RESULTS

Patients with cerebellar and intramedullary hemangioblastomas did not develop additional neurological deficits postoperatively. Two patients with brainstem tumors exhibited transient hemiparesis and caudal nerve palsy, respectively. Both patients recovered completely from their postoperative deficits. Preoperatively symptomatic patients with spinal tumors did not deteriorate nor improve after surgery. During the observed follow-up periods, no tumor recurrences were observed.

CONCLUSION

Central nervous system (CNS) hemangioblastomas in pediatric patients can be surgically treated with low morbidity. Based on our experience, we recommend considering also the surgical removal of asymptomatic hemangioblastomas with proven radiological progression to prevent the development of permanent neurological deficits. Molecular screening of every pediatric patient and family is mandatory to enable the detection of extraneurological tumors and the development of an efficient therapeutic strategy.

Long-term natural history of hemangioblastomas in patients with von Hippel–Lindau disease: implications for treatment

Object

In the course of their lives most patients with von Hippel–Lindau (VHL) disease require treatment for several symptom-producing hemangioblastomas of the cerebellum, brainstem, or spinal cord. However, many tumors never produce symptoms and do not require treatment. Detection at an early stage of lesions that will later produce symptoms and ultimately require treatment would allow for earlier excision of hemangioblastomas of the spinal cord, brainstem, or cerebellum, and may identify cerebellar hemangioblastomas that can be treated with radiosurgery at a stage before treatment is contraindicated because of tumor size or the presence of an associated cyst.

Methods

To identify features predictive of symptom development that might allow for earlier treatment of smaller, presymptomatic hemangioblastomas in patients with VHL disease, the authors reviewed and analyzed the serial clinical and imaging findings in all patients with VHL disease who were followed up at the National Institutes of Health for more than 10 years. Features predictive of symptom formation were determined by recursive partition and regression analyses.

Nineteen patients (10 men and nine women; mean age 32.6 ± 11.6 years) harboring a total of 143 hemangioblastomas were identified (mean follow-up duration 12.4 ± 1.4 years). Hemangioblastomas were located in the cerebellum (68 hemangioblastomas, 48% of patients), brainstem (17 hemangioblastomas, 12% of patients), and spinal cord (58 hemangioblastomas, 40% of patients). Despite measurable growth in almost all hemangioblastomas (138 lesions, 97% of patients), only 58 (41% of patients) became symptomatic. Hemangioblastomas grew in a stuttering pattern. (mean growth period 13 ± 15 months, mean quiescent period 25 ± 19 months). Twenty-six (45%) of the hemangioblastomas that eventually produced symptoms were not among the tumors that were apparent on the initial MR imaging study. Depending on location, the hemangioblastoma size and/or tumor and cyst growth rates predicted symptom development and the need for treatment (p < 0.05). Cerebellar hemangioblastomas growing faster than 112 mm3/ month or larger than 69 mm3 with associated tumor and cyst growth rates greater than 14 mm3/month became symptomatic (100% sensitivity, 72% specificity). Brainstem hemangioblastomas larger than 245 mm3 with growth rates greater than 0.1 mm3/month became symptomatic (75% sensitivity, 89% specificity). Spinal hemangioblastomas larger than 22 mm3 became symptomatic (79% sensitivity, 94% specificity).

Conclusions

Because hemangioblastomas exhibit a stuttering growth pattern, frequently remain asymptomatic, and do not require treatment for long intervals, unqualified radiographic progression is not an indication for treatment. Basing the decision to intervene in individual tumors solely on radiographic progression would have resulted in approximately four additional procedures per patient during the 10-year study period. Threshold values are presented for tumor size and/or tumor and cyst growth rates that can be used to predict symptom formation and future need for treatment.

Malignant transformation and new primary tumours after therapeutic radiation for benign disease: substantial risks in certain tumour prone syndromes

In recent years the use of radiation treatment for benign tumours has increased with the advent of stereotactic delivery and, in particular, single high dose gamma knife therapy. This has been particularly true for benign CNS (central nervous system) tumours such as vestibular schwannoma, meningioma, pituitary adenoma, and haemangioblastoma. While short term follow up in patients with isolated tumours suggests this treatment is safe, there are particular concerns regarding its use in childhood and in tumour predisposing syndromes. We have reviewed the use of radiation treatment in these contexts with particular regard to malignant transformation and new tumour induction. This review indicates that much more caution is warranted regarding the use of radiation treatment for benign tumours in childhood and in tumour prone conditions such as the neurofibromatoses.

Treatment of recurrent cerebellar hemangioblastoma with external radiotherapy in a patient with von Hippel-Lindau disease: a case report and review of the literature

Von Hippel-Lindau Disease, a multisystem familial cancer syndrome, is inherited as an autosomal-dominant trait. Common manifestations of the disease are retinal, cerebellar and medullary hemangioblastomas; renal cysts and carcinomas; pancreatic cysts; pheochromocytoma; and papilllary cystadenoma of the epididym. We report the case of a 40-year-old man with type I von Hippel-Lindau disease treated with external radiotherapy for recurrent cerebellar hemangioblastoma.

Central nervous system manifestations in VHL: genetics, pathology and clinical phenotypic features

This review focuses on CNS hemangioblastomas in von Hippel-Lindau (VHL) disease. The pathogenesis of these lesions remains unclear to date; however, biallelic inactivation of the VHL tumor suppressor gene is thought to be an important step. These benign tumors occur frequently in patients with VHL disease and produce symptoms by mass effect either by the tumor itself or an accompanying cyst or edema. Furthermore, cases of spontaneous hemorrhage have been described. Genetic testing for VHL germline mutations is recommended in all patients with hemangioblastoma and yearly screening, including MRI of the brain and spine, is recommended for all VHL disease patients. Treatment of these tumors is mainly surgical. In general, surgery is indicated in symptomatic hemangioblastomas and eventually also in asymptomatic tumors that exhibit radiographic progression. However, since most VHL disease patients harbor multiple lesions, a careful individual decision must be made in each case. The tumors can usually be completely removed by dissection in the plane between tumor and CNS tissue and coagulating and cutting of the numerous feeding vessels with low power. As long as consequent yearly surveillance is performed and lesions are adequately treated in time, the prognosis of CNS hemangioblastomas in VHL disease is good. Preoperative neurological deficit, however, will not improve after surgery in most patients. Local tumor recurrences are rare.