Pathological and haematological aspects of posterior fossa haemangioblastomata

Polyglobulia in patients with hemangioblastomas is related to tumor size but not to serum erythropoietin

Background

Hemangioblastomas are associated with elevated hemoglobin (Hb) levels (polyglobulia), which is associated with a higher risk for cerebral stroke, cardiac infarction and pulmonary embolism. The pathomechanism of polyglobulia remains unclear and different theories have been postulated. Among those are elevated serum erythropoietin (EPO) levels caused by secretion of the tumor or associated tumor cyst.

Methods

To elucidate the pathomechanism, we systematically investigated the relation between polyglobulia, serum EPO level, size of the solid tumor and associated cyst in hemangioblastomas. We prospectively evaluated hemoglobin and EPO levels in a series of 33 consecutive patients operated on hemangioblastomas in our center. We measured the size of the solid tumor and associated cyst in magnetic resonance imaging. Statistical evaluations were performed using the Fisher's exact test and student's t-test.

Results

As a result five patients had elevated hemoglobin levels. Only one of these had an elevated serum EPO level. Of 26 patients with normal hemoglobin levels, 4 patients had elevated EPO levels.Patients with low or normal hemoglobin levels (84%) had an average tumor size of 0.8 cm³, which differed significantly from patients with elevated hemoglobin levels (16%), who had an average solid tumor size of 8.0 cm³ (p < 0.05). We did not observe a significant correlation between EPO levels or polyglobulia and associated cysts.

Conclusions

We therefore conclude that in contrast to previous case reports and interpretations, our data show no correlation between polyglobulia and EPO levels or associated cysts in patients with hemangioblastomas. In fact, it is the size of the solid tumor that correlates with polyglobulia.The study was retrospectively registered in the German Clinical Trial Registry on 10 July 2014; Trial registration: DRKS00006310.

Hemangioblastomas and neurogenic polyglobulia

BACKGROUND

Neurogenic polyglobulia occurs with central nervous system hemangioblastomas. Among the suggested mechanisms are extramedullary hematopoiesis in the tumor tissue and germline mutations of the von Hippel-Lindau (VHL) tumor suppressor gene.

OBJECTIVE

To determine the frequency and driving mechanisms of polyglobulia in central nervous system hemangioblastomas.

METHODS

We performed a retrospective analysis of pre- and postoperative (at 3 and 12 months) hemoglobin levels in a consecutive series of patients with hemangioblastomas operated on in our institution from 1996 to 2009. We performed molecular genetic analyses for mutations of the VHL tumor suppressor gene.

RESULTS

Preoperative hemoglobin levels were available from 164 patients. The average hemoglobin level (15.2 g/dL in males and 13.1 g/dL in females) was within normal range according to our standards. Of 22 patients with increased preoperative hemoglobin levels (>17 g/dL in males and >15 g/dL in females), 8 presented with pathological hemoglobin (>18.5 g/dL in males and >16.5 g/dL in females) according to World Health Organization criteria. Surgical removal of the hemangioblastoma resulted in a permanent cure of polyglobulia in all patients. Six of the 8 patients with pathological hemoglobin elevation carried a germline mutation of the VHL tumor suppressor gene.

CONCLUSION

Neurogenic polyglobulia occurs in a subset of patients with hemangioblastomas. This phenomenon is mostly observed in VHL mutation carriers, but also occurs in patients with sporadic hemangioblastomas. Removal of the tumor results in the permanent cure of polyglobulia. Our observations suggest that polyglobulia is an effect by the tumor itself, either due to paraneoplasia or extramedullary hematopoiesis.

Sporadic intracranial haemangioblastomas: surgical outcome in a single institution series

BACKGROUND

Haemangioblastomas are benign vascular tumours that may appear sporadically or in von Hippel-Lindau disease. Despite their higher incidence, sporadic haemangioblastomas have been less studied than syndromic ones. In this article, we evaluate the specific features, outcome and quality of life of patients with intracranial sporadic haemangioblastomas (ISHs) operated on in our institution.

METHODS

Between 1998 and 2010, 38 patients harbouring 38 ISHs were operated on in our department. Their clinical, biological, radiological and surgical features were retrospectively reviewed. All patients were contacted for a quality-of-life (QOL) survey assessed by the Short Form 36 questionnaire (SF36). The mean duration of follow-up was 40 months (13-108 months).

RESULTS

ISH represented 0.9 % of primary intracranial neoplasms treated in our centre during this period. Patients comprised 23 men and 15 women with a mean age of 47 years. None had polycythaemia. Cerebellar locations accounted for 79 % of ISHs, and brainstem ISH with involvement of the floor of the fourth ventricle represented 11 % of ISHs. At last follow-up, two patients harbouring solid medulla oblongata haemangioblastoma had died following severe bulbar syndrome and five patients had died of unrelated causes. One patient had multiple surgeries for three recurrences. Tumoral control was achieved in all cases at last follow-up. Results of the SF-36 questionnaire were as follows: median physical functioning score 100 (range 0-100), median physical problems score 100 (range 0-100), median bodily pain score 100 (range 45-100), median social functioning score 100 (range 25-100), median general mental health score 84 (range 40-92), median emotional problems score 100 (range 0-100), median vitality score 70 (range 35-80) and median general health perceptions score 70 (range 35-100). Mean QOL scores were similar to the general healthy population.

CONCLUSION

Surgery of ISH provides good QOL and tumoral control except for those located in the medulla oblongata. We recommend considering a careful multimodal therapeutic approach, including radiosurgery for these specific locations.

Long-term prognosis of hemangioblastomas of the central nervous system: Clinical and immunohistochemical study in relation to recurrence

The long-term prognosis and immunohistochemical findings for the expression of VEGF (vascular endothelial growth factor), p53 protein, and proliferative potential with MIB-1 were evaluated in six patients with VHL (von Hippel-Lindau) disease and seven patients with sporadic hemangioblastomas in relation to recurrent or new central nervous system (CNS) hemangioblastomas following treatment. Sporadic CNS hemangioblastomas were treated by total removal, and they demonstrated a good long-term prognosis without neurological deficits and no recurrence. However, even if total removal of the CNS hemangioblastomas in patients with VHL disease was performed initially, new lesions, consisting of small multiple hemangioblastomas, recurred in areas remote from the primary region in three of four patients during long-term follow-up. Such newly developed hemangioblastomas in patients with VHL disease could reflect the biological multipotentiality of CNS hemangioblastomas that were not detected during the initial operation. All of the hemangioblastomas displayed extensive overexpression of VEGF protein. The immunohistochemical findings for VEGF protein, p53 protein, and MIB-1 did not differ significantly between the sporadic and VHL disease-associated hemangioblastomas. In conclusion, since patients with VHL disease are at risk of developing new lesions, the management of hemangioblastomas in patients with VHL disease represents a more prolonged and difficult task.

Stereotactic multiple are radiotherapy. IV--Haemangioblastoma

Our initial experience in the treatment of haemangioblastoma using conventional external beam radiotherapy and stereotactic radiotherapy (radiosurgery), by the linear accelerator method, is reported. Six haemangioblastomas in five patients were treated with a mean follow-up of 40 months (range 14-60). Five haemangioblastomas in four patients were treated with stereotactic radiotherapy, where four showed complete radiological response and the fifth was static. Neurological symptoms and signs improved in those patients. The sixth haemangioblastoma was situated close to the pituitary and optic chiasm, and was treated with conventionally fractionated external beam radiotherapy. The lesion showed partial response. No complications were noted in this patient group. This series complements and extends the relatively sparse published literature demonstrating that radiotherapy is an effective option for treating haemangioblastomas. Radiosurgery often lends itself particularly well to these discrete lesions allowing highly focused treatment. For patients with multiple and metachronous cerebellar haemangioblastomas as part of the von Hipple-Lindau syndrome, the data support a policy of conventionally fractionated external beam radiotherapy to the whole cerebellum of 50-55 Gy followed, after a period of time, by radiosurgery to persisting lesions (patients 3 and 4).

Hemangioblastoma of the optic nerve: case report

An optic nerve hemangioblastoma arising in the optic nerve of a patient with von Hippel-Lindau syndrome is reported. This represents the 10th published example of a hemangioblastoma arising at this site, the second description of the magnetic resonance imaging features of a hemangioblastoma at this location, and the second patient from whom an optic nerve hemangioblastoma has been removed with the goal of preserving the optic nerve as well as vision. A majority of these optic nerve hemangioblastomas have arisen in patients with von Hippel-Lindau syndrome. All patients experienced progressive loss of vision either to blindness or surgical intervention, although a vast majority of the lesions were sharply demarcated from the adjacent nerve and, thus, potentially resectable. Optic nerve hemangioblastomas are a rare cause of blindness but potentially preventable when treated with a conservative surgical approach aided by neuroimaging guidance. The recognition of discordance between the degree of vision loss and the extent or progression of a retinal hemangioblastoma may be an important clue to diagnosis in the patient with von Hippel-Lindau syndrome.

Radiotherapeutic considerations in the treatment of hemangioblastomas of the central nervous system

Twenty-seven hemangioblastomas of the central nervous system were treated at the Mayo Clinic with radiation therapy from January 1963 to August 1983. Six patients had von-Hippel Lindau syndrome, and four presented with polycythemia. The median age among the 15 males and 12 females was 48 years (range 20-68). Two clinical groups were apparent: those that received postoperative radiation therapy for clinically suspect, or microscopically positive margins (6 patients) and those who underwent therapy for gross residual disease (20 patients). One patient did not fall into either group because his initially unresectable tumor was treated with planned pre-operative radiotherapy to 40 Gy and was subsequently successfully cured by surgery. Because the combined modality approach did not allow assessment of local control with radiation alone, he was excluded from the gross residual cohort in terms of time-dose relationship analysis. The cohort with gross residual disease was particularly unfavorable as 12 of these patients had developed 17 local recurrences prior to radiation. Three had multiple lesions, and four had the von-Hippel Lindau syndrome. In-field disease control appeared to be improved when patients were treated more aggressively. Patients treated to a dose of 50 Gy manifested local control in 4/7 (57%) vs 4/12 (33%) in patients treated to less than 50 Gy. In-field local control was also better if patients received a TDF greater than 75 (local control in 66%) vs a TDF of 65-75 (local control in 22%). Actuarial analysis of in-field disease control showed more aggressive treatment improved control whether analyzed by dose level (greater than or equal to 50 Gy vs less than 50 Gy, or TDF greater than 75 vs less than 75). Four of the six patients who received radiation therapy for microscopically positive or clinically suspect margins achieved local control. Both patients manifesting in-field relapse were successfully surgically salvaged. Overall survival for the entire group of 27 patients was 85%, 58%, 58%, and 46% at 5, 10, 15, and 20 years, respectively. Recurrence-free survival was 76%, 52%, and 42% at 5, 10, and 15 years, respectively. Half of all in-field recurrences had occurred by 2 years, but the remaining half recurred from 5.6 to 14.4 years. Patients who developed in-field failure usually died from disease with a median survival of only 1.5 years, but surgical salvage was accomplished in 4/12. Hydro-myelia developed in two patients and required operation. Surveillance for systemic tumors also was important and revealed seven benign and four malignant tumors.(ABSTRACT TRUNCATED AT 400 WORDS)

Erythropoietin in haemangioblastoma: immunohistochemical and electron microscopy studies

Immunohistochemical studies for erythropoietin were carried out in six capillary haemangioblastomas, three of which were also studied by electron microscopy. The immunohistochemical studies showed that positively stained cells were scattered in the vicinity of capillaries, and that neither endothelial cells nor stromal cells were stained. In their morphology and distribution, the positively stained cells were identical to mast cells as observed by electron microscopy. In one case, erythropoietin was demonstrated in the cyst fluid of the tumour. These findings suggest that mast cells with abundant secreting granules in haemangioblastomas are capable of producing erythropoietin.

Erythropoietin in capillary hemangioblastoma. An immunohistochemical study

Capillary hemangioblastoma is a tumor known to be associated with secondary polycythemia. Therefore, specimens from ten hemangioblastomas were studied by immunohistochemistry for the presence of erythropoietin, renin substrate, and for various endothelial, histiocytic and glial markers. In all tumors scattered cells among the stromal cells showed a positive-staining reaction with both anti-erythropoietin and anti-renin substrate. The same cells also stained positively for alpha-1-anti-trypsin. It is concluded that, in addition to the capillary endothelial cells, pericytes and stromal cells, capillary hemangioblastomas harbor cells containing and perhaps producing renin substrate and/or erythropoietin or a substance with similar antigenic determinants.

Selective localization of gamma-enolase in stromal cells of cerebellar hemangioblastomas

Three cases of cerebellar hemangioblastoma were studied using the immunoperoxidase technique to localize gamma-enolase, also known as neuron-specific enolase. The stromal cells demonstrated positive staining for gamma-enolase, while endothelial cells and pericytes showed no reactivity. Two vascular lesions, an angiosarcoma and a cutaneous angioma, were studied and found to be nonreactive for gamma-enolase. All tumors were also tested for factor VIII/von Willebrand factor, glial fibrillary acidic protein, and the S-100 protein. The lack of expression of gamma-enolase in endothelial cells of hemangioblastomas demonstrates a clear antigenic distinction from neighboring gamma-enolase-positive stromal cells. The significance of this finding and its implications for stromal cell histogenesis are discussed.

Posterior fossa haemangioblastomas in Northern Ireland: a clinico-epidemiological study

A retrospective study of 25 patients who presented with posterior fossa haemangioblastomas to the Northern Ireland Regional Neurosurgical Centre over the past 25 years has been carried out. The epidemiological and clinical features and the results after operative treatment are presented and compared with other series. Posterior fossa haemangioblastomas were more common in female than in male patients and solid tumours accounted for 40% of all cases. While only two patients had associated polycythaemia, five patients (20%) were found to have persistent leucocytosis pre-operatively, while 24% had von Hippel-Lindau complex including two patients who were operated upon for an associated spinal haemangioblastoma. Of particular interest was a patient who had neurofibromatosis. There was no perioperative deaths. Patients with solid tumours fared badly in the long term compared with those who had a cystic type.

Syrinx of the conus medullaris and filum terminale in association with multiple hemangioblastomas

A patient with multiple hemangioblastomas and syrinxes of the cerebellum and spinal cord is presented. An additional mass imaged at the L-3 vertebral level was identified by percutaneous syringography as a bilobular syrinx extending from the conus medullaris into the filum terminale. At surgery the syrinx was opened into the caudal cerebrospinal fluid space and the several hemangioblastomas excised. These spinal tumors all appeared to arise in juxtaposition to the posterolateral sulcus and dorsal sensory roots.

Posterior fossa haemangioblastomas: angiography versus computed tomography

A series of 57 patients harbouring a total of 63 haemangioblastomas of the posterior fossa is reviewed. Some clinical data are pointed out and the findings of vertebral angiography and computed tomography scanning performed in 61 and 38 lesions, respectively, are examined. The results obtained in the last 38 cases, undergoing both examinations, are compared, and some notes on differential diagnosis with other expansive lesions of the posterior fossa are given.

[Hemangioblastomas of the central nervous system. A clinical study]

In a survey of 46 patients with haemagioblastoma of the CNS (Neurology Dept. University Hamburg, 1950-1980) most (n = 40) were found to have angioblastomas of the cerebellum (Lindau tumors). Of these patients 21 were re-examined in 1983. Headache was the most frequent initial symptom (43%), and within this group one-third (10%-15%) had dizziness, sensorymotor deficits and cerebellar gait disturbances. Signs of elevated intracranial pressure much more often led to the correct diagnosis than dizziness or dystaxia. After the introduction of CCT to the diagnostic procedure the combined evaluation of angiography of the vertebral arteries and CCT always permitted the correct diagnosis. The low neurosurgical mortality rate (13.5%) has decreased to 0% within the last decade. No relapses were found in 21 re-examinations including CCT and EOG compared to a frequency of 9.7% in all 46 cases. Significantly less often than expected from other data we found: signs of possible hereditary influence (0%), multiple tumor localization combined with angiomatosis retinae (0%), polyglobulia (10.8%). Psychopathologically relevant signs (45.6%) were, in all cases, combined with signs of increased intracranial pressure. The results of our re-examination demonstrate that late postoperative deficits as well as possible relapses are earlier and more precisely evaluated by the combined use of clinical examination, CCT and EOG.

Haemangioblastomas of the posterior cranial fossa

The clinical features, diagnostic and surgical aspects of haemangioblastoma of the posterior cranial fossa are discussed in the light of a series of 61 personal cases and the published data. CT and vertebral angiography are compared as diagnostic tools. With the aid of microsurgery even haemangioblastomas of the brainstem and fourth ventricle can be removed successfully.

Erythropoietin levels in posterior fossa haemangioblastoma

Using an in vitro bioassay, erythropoiesis stimulating activity has been measured in serum, cyst fluids and tumour homogenates from fourteen patients with cerebellar haemangioblastoma. Only two patients had elevated peripheral blood red cell counts and haemoglobin concentrations. Significantly elevated serum erythropoiesis stimulating activity was found in only one patient. High level, however, were detected in seven out of the fourteen cyst fluids and in the two homogenates tested. The dose response lines from these paralleled those of normal human erythropoietin. It was possible to neutralise the erythropoiesis stimulating activity in the cyst fluids with anti-human erythropoietin serum, indicating its similarity to erythropoietin, the normal erythropoietic regulating hormone. Significant release of the erythropoietic stimulating factor from the cyst fluids into the blood seemed to be an uncommon occurrence.

Glial fibrillary acidic protein in stromal cells of some capillary hemangioblastomas: significance and possible implications of an immunoperoxidase study

Thirty-nine hemangioblastomas from 26 patients were studied by the immunoperoxidase method for GFA protein. Reactive gliosis in the form of trapped GFA protein-positive astrocytes or astrocytic cell processes penetrated the margins of all the neuraxial tumors and none of those occurring on nerve roots or in the tumor explants maintained in an organ culture system. Gliosis was especially prominent in tumors recurring after surgical excision or in patients with a long history of tumor. In six tumors, representing both the reticular and the cellular variants of hemangioblastoma, GFA protein-positive stromal cells were also found, chiefly in the periphery of the neoplasma: all these tumors were surrounded by dense reactive gliosis. Four hypotheses accounting for the presence of GFA protein-positive stromal cells are considered: (1) The tumors are astrocytomas. (2) The GFA protein-positive cells are not neoplastic but lipidized or altered reactive astrocytes. (3) The tumors are mixed and partly composed of neoplastic astrocytes. (4) The stromal cells are capable of taking up extracellular GFA protein derived from the adjacent reactive astrocytes. The last of these hypotheses is the most consistent with the collective evidence derived from the histological findings. It implies that the presence of GFA protein in the cytoplasm of a cell does not necessarily establish that the cell is glial. The possibility of uptake of GFA protein by non-glial cells must be considered if dense gliosis is present in the vicinity.

Determination of plasma erythropoietin levels: an early marker of tumor activity

A young female patient developed erythrocytosis during the third recurrence of a cerebellar hemangioblastoma. Elevated erythropoietin levels were found in the patient's plasma with normalization after resection of the tumor. High erythropoietin titers were also found in the tumor saline extract. A fourth recurrence of the tumor was heralded by a rising plasma erythropoietin level and gradual erythrocytosis despite the absence of change in the clinical picture or the brain scan. In this case, serial plasma erythropoietin determinations served as a useful early marker of the tumor activity.

The complementary nature of computed tomography and angiography in the diagnosis of cerebellar hemangioblastoma

Cerebellar hemangioblastomas were seen in seven persons, five being members of the same family. All were studied with constrast enhanced CT scans and vertebral angiograms. The CT scans were superior for demonstrating the cystic component of the tumors and associated hydrocephalus, features not usually evident on the angiograms. The angiograms were superior for revealing the vascular nature, supply and drainage of the tumors. In several patients the angiograms revealed more tumors than could be seen by CT. Both CT and angiography contribute important information in the diagnosis of these neoplasms.

Clinical and surgical aspects of posterior fossa haemangioblastomata

A retrospective study has been carried out on 67 patients with posterior fossa haemangioblastomata. Clinical details are presented, and the problems of diagnosis discussed. A fresh definition of the von Hippel-Lindau complex is put forward. The results of surgery are good for patients with solitary and sporadic tumours.