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The physical absorbed dose enhancement by the inclusion of gold and bismuth nanoparticles fabricated into water-equivalent PRESAGE dosimeters was investigated. Nanoparticle-loaded water-equivalent PRESAGE dosimeters were irradiated with superficial, synchrotron and megavoltage X-ray beams. The change in optical density of the dosimeters was measured using UV-Vis spectrophotometry pre- and post-irradiation using a wavelength of 630 nm. Dose enhancement was measured for 5 nm and 50 nm monodispersed gold nanoparticles, 5-50 nm polydispersed bismuth nanoparticles, and 80 nm monodispersed bismuth nanoparticles at concentrations from 0.25 mM to 2 mM. The dose enhancement was highest for the 95.3 keV mean energy synchrotron beam (16-32%) followed by the 150 kVp superficial beam (12-21%) then the 6 MV beam (2-5%). The bismuth nanoparticle-loaded dosimeters produced a larger dose enhancement than the gold nanoparticle-loaded dosimeters in the synchrotron beam for the same concentration. For the superficial and megavoltage beams the dose enhancement was similar for both species of nanoparticles. The dose enhancement increased with nanoparticle concentration in the dosimeters; however, there was no observed nanoparticle size dependence on the dose enhancement.

Purpose: Titanium dioxide nanoparticles (TiO 2 NPs) have been investigated for their role as radiosensitisers for radiation therapy. The study aims to increase the efficiency of these NPs by synthesising them with samarium., Methods: Samarium-doped TiO 2 NPs (Ti(Sm)O 2 NPs) were synthesised using a solvothermal method. Transmission electron microscopy (TEM), X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDS) were performed for characterising of the Ti(Sm)O 2 NPs. The intracellular uptake and cytotoxicity were assessed in vitro using A549 and DU145 cancer cell lines. Furthermore, the effect of dose enhancement and generation of reactive oxygen species (ROS) in response to 6 MV X-rays was evaluated. Additionally, the image contrast properties were investigated using computed tomography (CT) images., Results: The synthesised Ti(Sm)O 2 NPs were about 13 nm in diameter as determined by TEM. The XRD pattern of Ti(Sm)O 2 NPs was consistent with that of anatase-type TiO 2 . EDS confirmed the presence of samarium in the nanoparticles. At 200 μg/ml concentration, no differences in cellular uptake and cytotoxicity were observed between TiO 2 NPs and Ti(Sm)O 2 NPs in both A549 and DU145 cells. However, the combination of Ti(Sm)O 2 NPs and X-rays elicited higher cytotoxic effect and ROS generation in the cells than that with TiO 2 NPs and X-rays. The CT numbers of Ti(Sm)O 2 NPs were systematically higher than that of TiO 2 NPs., Conclusions: The Ti(Sm)O 2 NPs increased the dose enhancement of MV X-ray beams than that elicited by TiO 2 NPs. Samarium improved the efficiency of TiO 2 NPs as potential radiosensitising agent., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

This research investigated the dose response and post-irradiation stability of water-equivalent PRESAGE ® dosimeters exposed to synchrotron radiation. Water-equivalent PRESAGE ® dosimeters were irradiated up to 1000 Gy in a synchrotron x-ray beam with a mean energy of 95.3 keV. The change in optical density was measured using UV/visible spectrophotometry pre- and post-irradiation using a wavelength of 630 nm. Dose response was found to be approximately linear from 0-200 Gy with saturation occurring above 300 Gy. The post-irradiation stability was determined by measuring the change in optical density at 10, 30, 60, 180, 420 min and 7, 21 and 33 d post-irradiation for three groups of dosimeters stored at different temperatures. Each group had two dosimeters irradiated at 50, 100, 200 and 300 Gy and each group was stored at a different temperature following irradiation: room temperature (22 °C), 4 °C and  -18 °C. The optimal time for readout of the dosimeters varied with the post-irradiation storage temperature. The room temperature group had an optimal time-to-readout of 10 min for maximum signal before fading, while the 4 °C group was reasonably stable from 90 min to 1 week. The  -18 °C group showed the least amount of ongoing post-irradiation development and fading with an optimal readout window from 30 min to 21 d. The intra-batch variation between the mean of each temperature control group was 4.2% at 10 min post-irradiation.

Purpose: Synchrotron Radiation Therapy techniques are currently being trialed and commissioned at synchrotrons around the world. The patient treatment planning systems (TPS) developed for these treatments use simulated data of the synchrotron x-ray beam to produce the dosimetry in the treatment plan. The purpose of this study was to investigate a water equivalent PRESAGE ® dosimeter capable of 3D dosimetry over an energy range suitable for synchrotron x-ray beams., Methods: Water equivalent PRESAGE ® dosimeters were fabricated with a radiological effective atomic number similar to water over an energy range of 10 keV to 10 MeV. The dosimeters were irradiated at various energies, scanned using optical CT (OCT) scanning and compared to ion chamber measurements. Percentage depth dose and beam profiles of the synchrotron beam were compared to Monte Carlo (MC) model simulations., Results: The PDD profiles of the water equivalent PRESAGE ® agreed with ion chamber measurements and MC calculations within 2% for all keV energies investigated. The PRESAGE ® also showed good agreement to the MC model for depths below 5 mm of the synchrotron beam where ion chamber data do not exist. The spatial resolution of the OCT was not sufficient to accurately measure the penumbra of the synchrotron beams compared to MC calculations or EBT3 film; however, the water equivalent PRESAGE ® was able to verify dose profile characteristics of the MC model., Conclusions: The radiological response of a water equivalent PRESAGE ® dosimeter has been validated for synchrotron x-ray beam energies along with the ability to independently verify dose distributions of a MC model., (© 2018 American Association of Physicists in Medicine.)

Purpose: Microbeam radiation therapy (MRT) techniques are under investigation at synchrotrons worldwide. Favourable outcomes from animal and cell culture studies have proven the efficacy of MRT. The aim of MRT researchers currently is to progress to human clinical trials in the near future. The purpose of this study was to demonstrate the high resolution and 3D imaging of synchrotron generated microbeams in PRESAGE® dosimeters using laser fluorescence confocal microscopy., Methods: Water equivalent PRESAGE® dosimeters were fabricated and irradiated with microbeams on the Imaging and Medical Beamline at the Australian Synchrotron. Microbeam arrays comprised of microbeams 25-50 μm wide with 200 or 400 μm peak-to-peak spacing were delivered as single, cross-fire, multidirectional, and interspersed arrays. Imaging of the dosimeters was performed using a nikon a1 laser fluorescence confocal microscope., Results: The spatial fractionation of the MRT beams was clearly visible in 2D and up to 9 mm in depth. Individual microbeams were easily resolved with the full width at half maximum of microbeams measured on images with resolutions of as low as 0.09 μm/pixel. Profiles obtained demonstrated the change of the peak-to-valley dose ratio for interspersed MRT microbeam arrays and subtle variations in the sample positioning by the sample stage goniometer were measured., Conclusions: Laser fluorescence confocal microscopy of MRT irradiated PRESAGE® dosimeters has been validated in this study as a high resolution imaging tool for the independent spatial and geometrical verification of MRT beam delivery.

In vivo dosimetry is recommended as a defence-in-depth strategy in radiotherapy treatments and is currently employed by clinics around the world. The characteristics of a new optically stimulated luminescence dosimetry system were investigated for the purpose of replacing an aging thermoluminescence dosimetry system for in vivo dosimetry. The stability of the system was not sufficient to satisfy commissioning requirements and therefore it has not been released into clinical service at this time.

Complex intensity-modulated radiation therapy (IMRT) treatment plans require rigorous quality assurance tests. The aim of this study was to independently verify the delivered dose inside the patient in the region of the treatment site. A flexible naso-gastric tube containing thermoluminescent dosimeters (TLDs) was inserted into the oesophagus via the sinus cavity before the patient's first treatment. Lead markers were also inserted into the tube in order that the TLD positions could be accurately determined from the lateral and anterior-posterior electronic portal images taken prior to treatment. The measured dose was corrected for both daily linac output variations and the estimated dose received from the portal images. The predicted dose for each TLD was determined from the treatment planning system and compared to the measured TLD doses. The results comprise 431 TLD measurements on 43 patients. The mean measured-to-predicted dose ratio was 0.988 +/- 0.011 (95% confidence interval) for measured doses above 0.2 Gy. There was a variation in this ratio when the measurements were separated into low dose (0.2-1.0 Gy), medium dose (1.0-1.8 Gy) and high dose (>1.8 Gy) measurements. The TLD-loaded, naso-oesophageal tube for in vivo dose verification is straightforward to implement, and well tolerated by patients. It provides independent reassurance of the delivered dose for head and neck IMRT.

We report our remarks on 22 patients, 80 years of age and older, who were treated for glioblastoma multiforme. The 16 patients who underwent a multimodality treatment (surgery + radiotherapy + chemotherapy) had an average survival of 16.7 months versus the 5.8 months of the 8 patients treated with biopsy followed by radiotherapy and/or chemotherapy (log-rank test, P < 0.001). Moreover, we point out the importance of MGMT hypermethylation as a significant prognostic factor: the 9 patients with nonmethylated MGMT had a mean survival of 7.7 months vs. 17.9 months of the 13 patients with the MGMT promoter methylated (log-rank test, P = 0.0006). Several studies have pointed out age as an important negative factor for the outcome of elderly patients affected by glioblastoma multiforme. Elderly patients with a diagnosis of glioblastoma multiforme are thus generally excluded from clinical trials of treatment for the neoplasm, because it is a common opinion that the prognosis for such patients is particularly poor. On the contrary, according to our clinical and surgical experience, we firmly believe that patients older than 80 years with a histologically proven diagnosis of glioblastoma multiforme and in good health conditions (Karnofsky performance status >60) should be treated in the same way as younger patients.

Brain metastases from renal carcinoma may appear even a long time after surgical treatment of the primary tumor. The authors present 2 series of patients, one of which has already been published and the other new, for a total of 4 cases of brain metastasis from renal carcinoma with late onset, which occurred 13, 17, 26 and 12 years after primary surgical treatment. The other cases described in the literature were also critically reviewed.

Background: The primary aim of surgical treatment for falcotentorial meningiomas is gross total excision. The vital surrounding brain structures make this a complex task. Seeking elements that might facilitate presurgical planning we reviewed our surgical records of falcotentorial meningiomas treated during the past 20 years., Methods: Between 1975 and 1996, in the Neurosurgical Unit at the University of Rome, "La Sapienza," 13 consecutive patients underwent surgery for falcotentorial meningiomas that had been localized on preoperative imaging and confirmed by histology. The surgical approach varied according to the site of the tumor., Results: Nine meningiomas were totally removed and 4 subtotally. Three patients (23.0%), all treated early in the series, died after the operation. Ten patients (76.9%) survived: 3 (23.0%) had postoperative neurologic complications necessitating reintervention, and 7 patients (53.8%) had an uneventful postoperative course. Two of the 4 patients who had subtotal resections had regrowth at 1 year that responded to radiosurgery., Conclusions: The ideal surgical approach to falcotentorial meningiomas should allow gross total removal and minimum brain retraction while safeguarding the galenic system and other vital neighboring structures. Toward achieving this aim we propose detailed preoperative imaging studies to classify falcotentorial meningiomas according to their site and direction of growth-craniocaudal or anteroposterior-in relation to the cerebellar tentorium.

Background: Continuous research into new strategies and chemotherapy agents for the treatment of malignant high-grade gliomas have led to the synthesis of a new chemotherapy drug, temozolomide (TMZ), with a lower toxicity profile compared to conventional chemotherapy agents, such as nitrosoureas. Temozolomide is an oral alkylating chemotherapy agent licensed for the treatment of recurrent high-grade gliomas, anaplastic astrocytoma (AA) and glioblastoma multiforme (GBM). Because of its favorable pharmacokinetic and pharmacodynamic properties and improved tolerability, TMZ is now under investigation for concomitant use with radiotherapy in patients with newly-diagnosed GBM. We present a phase II clinical trial investigating the efficacy and safety of radio-chemotherapy combined treatment using TMZ, followed by six cycles of adjuvant chemotherapy with TMZ, in patients with newly-diagnosed GBM who have undergone debulking surgery or biopsy only., Patients and Methods: Twenty-one patients with newly histologically-diagnosed GBM were enrolled into this phase II clinical trial. In phase I of the study, TMZ (75 mg/m2/day per 7 days/wk for 6 weeks) was orally administered to patients concomitantly with radiotherapy (RT) (2 Gy per fraction once daily, per 5 days/wk for 6 weeks). In phase II of the study, four weeks after completion of RT, a monochemotherapy using TMZ was administered at the dosage of 200 mg/m2/day per 5 days every 28 days for 6 cycles. Primary end-points were the safety and tolerability profile of this two-phase combined treatment and secondary end-points were the objective response and survival rates at twelve months and eighteen months from study entry., Results: The one-year survival rate of patients treated with the investigated multimodality treatment was 58% and median survival time was 15.7 months. Concomitant RT plus TMZ (phase I) followed by adjuvant TMZ (phase 2) were well-tolerated; indeed, nonhematological adverse events were rare and mild to moderate in severity; grade 3 and 4 neutropenia and thrombocytopenia were the major-related hematological side-effects observed in only 2 and 3 of all patients in phase I and 4 patients in phase II. We found that the combination of radio- and chemo-therapy, in phase I of the study did not significantly increase the incidence and severity of hematological toxicity caused by the adjuvant TMZ-based chemotherapy administered in phase II of the study., Conclusion: The investigated multimodality treatment regimen was well-tolerated and prolonged survival while improving patients' quality of life.

Brain metastasis from hepatocarcinoma are a decidedly rare occurrence in countries where this pathology is most frequent. The authors describe a case of metastases from hepatocellular carcinoma in a patient suffering from post-HBV hepatic cirrhosis with hemorrhagic onset. The "stroke-like" presentation of the cerebral localization of the disease can be explained by both the important vascularization of the tumor and the frequent hemocoagulative alterations caused by the cirrhosis. The importance of diagnostic neuroradiology is briefly addressed, with reference to the fundamental role played by MRI. Surgery of these lesions does not present any particular technical problems as long as they are located in accessible areas and the patient's general and neurological conditions allow it. Postoperative radiotherapy seems to improve the quality and quantity of residual life, although the number of patients described in the literature is too small to draw any definite conclusion. Promising molecular biology studies are under way to evaluate the role of oncosuppresor gene expression in hepatocarcinogenesis and in the way the disease spreads.

Background: The purpose is to highlight the usefulness of CT angiography (CTA) in the diagnosis and surgical treatment of cerebral aneurysms., Methods: Thirty-one patients with subarachnoid haemorrhages were subjected to CT angiography and in those cases where this test did not reveal the aneurysm or did not supply sufficient information relating to it, subsequently a digital subtraction angiography was also performed. Each aneurysm-positive CTA was re-processed using the 3-D techniques, with the neuro-radiologist and the neuro-surgeon working in close co-operation., Results: In 27 cases the CTA diagnosed an aneurysm, and in the 4 cases where no vascular malformations were revealed, also the traditional angiography did not show any pathology. In 17 out of 18 cases operated on in order to clip the aneurysm, the CTA supplied all the information needed for the surgery and it was possibile to reconstruct images similar to those of the surgical field. This led to improvement in the programming of the surgical intervention; in 1 case only was it also necessary to perform the DSA before the operation., Conclusions: CT angiography, because it is non-invasive, easy to perform, diagnostically reliable, and because the 3-D re-constructions offer the chance to create images of the possible operating field, is the first-choice test to be adopted in the treatment of subarachnoid haemorrhages, even though in some cases the use of the traditional angiography is still necessary and should be carried out whenever the CTA does not reveal vascular malformations.

Purpose: EGR-1 is an immediate early gene with diverse functions that include the suppression of growth. EGR-1 is down-regulated many cancer cell types, suggesting a tumor suppressor role, and may critically involve the p53 pathway. The aim of this work was to measure the expression of EGR-1 and the p16/INK4a/ARF-Mdm2-p53 pathway status in fresh human gliomas., Experimental Design: Thirty-one human gliomas with different grades of malignancy were investigated for Egr-1 mRNA and the protein expression, frequency, and spectrum of p53 gene mutations, mdm2 gene amplification, and p16/INK4a/ARF allele loss., Results: The amplification of Mdm2 and the deletion of the p16/INK4a gene was found in 3 and 5 cases, respectively, whereas mutations of p53, including two novel mutations, were observed in 10 other cases. The three types of changes occurred strictly mutually exclusively, emphasizing that these genes operate in a common pathway critical to glioma progression. EGR-1 mRNA was significantly down-regulated in astrocytomas (14.7 +/- 5.1%) and in glioblastomas (33.6 +/- 10.0%) versus normal brain. Overall, EGR-1 mRNA was strongly suppressed (average, 15.2 +/- 13.9%) in 27 of 31 cases (87%), independent of changes in p16/INK4a/ARF and Mdm2; whereas 4 of 31 cases with residual EGR-1 expression as well as the highest EGR-1 variance segregated with p53 mutations. Immunohistochemical analyses confirmed the suppression of EGR-1 protein., Conclusions: These results indicate that EGR-1 is commonly suppressed in gliomas independent of p16/INK4a/ARF and Mdm2 and that suppression is less crucial in tumors bearing p53 mutations, and these results implicate an EGR-1 growth regulatory mechanism as a target of inactivation during tumor progression.

The presence and variant distribution of human herpesvirus 6 (HHV-6) was investigated by a nested polymerase chain reaction (PCR) in 118 biopsies from patients affected by nervous tissue tumor (115 primary tumors and 3 metastasis) and in 31 autopsy samples from the brain of healthy individuals. HHV-6 DNA sequences were detected in normal and neoplastic nervous tissue at a frequency of 32% and 37%, respectively. In both tissues, variant A was three times more frequent than the variant B. Peripheral blood lymphocytes (PBLs) derived from seven tumor affected patients contained the same variant as their respective brain sample, as judged by PCR. The expression of HHV-6 encoded immediate early protein p41 was detected by immunohistochemistry in neoplastic but not in normal brain. This may reflect viral reactivation from latency in immunocompromised patients. The seroepidemiological data indicated a frequency distribution of anti-HHV-6 antibodies in patients with brain tumors similar to that found in healthy donors.

Brain metastases from thyroid carcinoma is unusual, with a frequency of 1%. We report twelve patients, with single brain metastases and with a karnofsky performance scale score >60 at admission. No metastasis was seen during the uptake of iodine-131, even in the cases from differentiated thyroid carcinoma, suggesting absence of differentiation between primary and metastasic disease. The histopathology of thyroid carcinomas was anaplastic in five cases, differentiated in six, and medullary in one. Only in four patients, brain was the unique site of metastatic spread; in others, bones and lungs were also involved. All metastases were surgically removed, and all patients were treated with radiotherapy (45 Gy) in the postoperative course. The survival average was 19.8 months, and the quality of life was satisfactory in all patients. One patient remained alive till 5 years. Anaplastic histopathology and size of the primitive, and also bone involvement of thyroid disease were significant risk factors in our cases (p < 0.05). According to the literature, surgery is the best therapeutical choice. Alternative strategies in the management of brain metastasis, such as iodine-131 therapy, are discussed, paying particular attention to the relevant side effects.

We performed a clinical and genetic study of patients affected by cavernous angiomas (CA) of the nervous system. We examined initial signs and symptoms in sporadic and familial cases. We obtained clinical, neuroimaging and genetic data on 15 Italian patients with CA of the nervous system with positive, doubtful or apparently negative family history. Genetic markers surrounding three different gene regions (7q, 3q and 7p) were analysed. In one small family, genetic linkage was consistent with all chromosome loci. In another family with the unusual association of cerebral and spinal CA, linkage with chromosome 7q and, likely, 7p was excluded, while linkage with locus 3q was possible. Our results indicate that Italian families with CA may show genetic heterogeneity. Non-specific and subtle onset symptoms hide the presence of CA within families. Patients with multiple CA may have silent cerebral lesions confirming the low penetrance of clinical signs in spite of radiological ones.

Systemic metastases from ovarian carcinoma are frequent, but they rarely affect the central nervous system. The treatment of this type of metastases in not clear. Two cases of solitary cerebral metastasis from ovarian carcinoma are reported. Two patients, submitted to therapeutic protocol established for ovarian carcinoma, presented after 17 and 25 months respectively the appearance of symptoms from brain solitary metastasis without other metastases. They underwent surgery, radiotherapy and chemotherapy for solitary cerebral metastasis. Treatment of the brain lesion resulted in KPS improvement (KPS = 90) and survival was 16 and 30 months, respectively. From the 2 cases presented and the review of the literature, it appears that a better outcome may be obtained by a combined treatment of metastases, including surgery, radiotherapy and chemotherapy.

Methods: We report on 15 patients surgically treated for intraparenchymal brain metastases from sarcoma, including six osteosarcomas, five leiomyosarcomas, two malignant fibrous histiocytomas, and two alveolar soft-part sarcomas (ASPS)., Result: Median survival after craniotomy was 9.3 months. Patients with a preoperative Karnofsky performance score of > 70 survived for 12.8 versus 5.3 months for those with a Karnofsky performance score < 70 (p=0.03). Patients with evidence of only lung metastases at the time of surgery (nine cases) survived 8.6 months, which was similar to the 10.4-month survival for patients with disease limited to the brain (p=0.1). The two patients with alveolar soft-part sarcomas are alive at 15 and 20 months after surgery., Conclusion: We conclude that surgery is effective in treating selected patients with sarcoma metastatic to the brain and that patients with metastasis from ASPS may have a relatively good prognosis if they are surgically treated. The complete removal of all brain metastases and a Karnofsky performance score > 70 are associated with a favorable prognosis; the presence of concurrent lung metastases is not a contraindication to surgery.

Aim: Intradiploic epidermoid cyst is a slow-growing tumor affecting only rarely the cranial bones., Patient: The authors describe a case of intradiploic epidermoid cyst of the cranial vault in which there was a predominantly intracranial extension. Roentgenographic and CT findings do not permit a differential diagnosis. Complete removal of the cyst and its capsule was accomplished, with complete recovery., Conclusion: Total removal oft the tumor and its capsule is associated with a very good long-term prognosis without recurrences.

A case of intraparenchymal schwannoma is presented. A 61-year-old woman, with stigmata of von Recklinghausen's neurofibromatosis (NF-2), presented with a history of weakness of the right lower limb for 2 months. She was investigated by MR which showed a circular mass with a maximum diameter of 5 cm in the right parieto-occipital lobe. The tumor was removed in toto via a left parieto-occipital craniotomy. The patient was discharged two weeks after the operation and remains well now 2 years later. The clinical and neuroradiological findings of reported intraparenchymal schwannomas, including the case reported here, are discussed.

The authors report 11 patients with cerebral glioblastoma who lived at least 5 years after their initial diagnosis. There were 6 female and 5 male; the mean age was 39 years (range 24-55 years). All patients were treated surgically and postoperatively received whole-brain radiotherapy and chemotherapy. Five patients (45%) presented local recurrences after an average interval of 3.9 years from treatment. At average follow-up of 9 years (range 5-14 years), 7 patients (64%) were alive after an average interval of 8.1 years; 4 patients (36%) died from local relapse. Survival was influenced by patient age and, to a lesser degree, by treatment. A review of the literature, together with our own series, suggest that death from recurrence disease is unusual in glioblastoma patients who survive more than 5 years.

A retrospective review of 603 cases of intradural benign tumors of the cauda equina are presented (283 schwannomas and 320 ependymomas). For each tumor, the clinical course and long-term postoperative results were analyzed: it emerged that differential diagnosis between neurinomas and non tumoral lesions is not possible if based on clinical findings alone and that neuroradiological diagnosis is more accurate when MRI is employed. Long-term prognosis of neurinomas was always favourable, while in the ependymomas, early diagnosis gives excellent results because prognosis is apparently directly correlated to the length of preoperative clinical history.

Background: Numerous neoplasms within the CNS have been reported as radiogenic in origin; radiation-induced meningiomas are at least five times more numerous than gliomas or sarcomas in the world literature., Methods: The authors review 10 cases of cerebral meningiomas following high-dose radiotherapy in patients operated for neoplasm of the nervous system. The pathologic and clinical aspects of this unusual complication are analyzed in all cases in the world literature., Results: There is a female predominance (F-M ratio: 3:2) and the patients are young (mean age: 33.1 years; median: 29 years). The average latency period is 14.4 years (range: 9-21 years). The first disease is acute lymphocytic leukemia (ALL) in 40% of cases. Radiation induced meningiomas are atypical in four cases. Recurrence was observed in one case without malignant transformation., Conclusion: High-dose radiation-induced meningiomas have the following characteristics: (1) children appear particularly sensitive to the development of this tumor; (2) there is a female predominance, otherwise than is observed in low-dose meningioma; (3) these tumors present a peak frequency in the third decade of life; and (4) frequently, these tumors are atypical and recur. Finally, it is essential that every new case be reported to throw light on this particular pathologic correlation with its many grey areas.

Forty patients with multifocal and multicentric cerebral tumours were retrospectively studied. The patients were divided into two groups: ten patients with multicentric tumours (group A), and 30 patients with multifocal tumours. As far as their preoperative clinical history and the incidence of the various symptoms and signs are concerned, there were no significant differences between the two groups. CT permitted a correct diagnosis in 90% of the cases. All of the patients underwent the removal of the tumour(s) and received radiotherapy; 30 patients also received chemotherapy. In group A, nine patients died and one was lost to follow-up one year after treatment; the average survival was ten months from the appearance of the multicentric tumour. In group B, 29 patients died and one is still alive two years after treatment; the average survival was six months. We consider the problems of diagnosis and the long-term follow-up of patients.

The authors report 8 cases of central neurocytoma with a minimum follow-up of 3 years. Five patients were males and 3 females with average age of 21 years. All patients underwent surgical removal of tumor, and radiotherapy was delivered to 2 of the 3 patients in whom removal had been partial. At an average follow-up of 5 years, all patients are alive and none of them has presented signs of recurrence or progression of the disease. Some typical clinical and histological features of this tumor are pointed out.

Aims and Background: Gliomas of the conus medullaris often show characteristic clinical, radiological, and intraoperative features which differ from gliomas involving other parts of the spinal cord., Methods: Eight patients with histologically verified gliomas of the conus medullaris were diagnosed and studied., Results: There were five men and three women ranging in age from 21 to 59 years. Predominant initial symptoms were back pain (4 cases) and leg weakness (4 cases). The most common findings on admission were flaccid paraparesis with impaired sensation and bladder dysfunction. Postoperative magnetic resonance (MR) images with more than 95% removal of a tumour were defined as "subtotal removal" (noted in 4 of 8 cases), and less than 95% as "partial removal" (4 of 8 cases). All patients had postoperative radiotherapy. During the follow-up period ranging from 3 to 10 years, there was no tumour recurrence or regrowth on MR images., Conclusions: The postoperative radiotherapy in gliomas of the conus medullaris where total resection is not possible seems provide a beneficial effect on preventing tumour regrowth.

The authors report 19 cases of solitary cerebral metastases from malignant melanoma. In 15 patients, the primary lesion was known at the time the metastasis was diagnosed; deltoid-scapular in 4 cases, thoracic in 5, inguinal in 4 and neck in 2. The primary location was unknown in 4 patients. Presenting symptoms were: epileptic seizures in 9 cases, headache in 8, strength deficit of the limbs in 2. In 3 patients (16%) neurological symptoms were the first clinical sign of the systemic tumor; in 16 cases (84%) there was a long interval between treatment of the primary and appearance of the cerebral metastasis (average 3.8 years; median 3.4 years). All patients were submitted to surgery and radiotherapy (whole-brain in 14 and radiosurgery in 5). In 10 cases the lesion was removed 'en bloc' (no internal touch technique). Average survival was 9 months (median 8 months) and was influenced by 'en bloc' resection and whole-brain irradiation. None of the patients operated by the 'no touch technique' presented a recurrence.

The authors present a case of post-traumatic intracranial meningioma, selected according to the criteria specified in the relevant literature. Assessment of the clinical characteristics of our patient and those reported in the literature seems to confirm that, in some cases, head trauma may be a factor contributing to the development of meningioma.

The authors report 2 cases of cerebral meningiomas following high-dose radiotherapy in elderly patients treated for skull basaloma. These two are the first cases over 65 years old cases reported in the literature. The pathological and clinical characteristics of high-dose radio-induced meningiomas are the following: 1) children appear particularly sensitive to the development of this tumor; 2) there is a female patient predominance, in contrast to the male dominance observed in low-dose meningioma, 3) these tumors present a peak frequency in third decade of life; 4) frequently, these tumors are atypical and recur.

Two cases of intradural cavernous angioma of the cauda equina are reported, one of which presented with symptoms of subarachnoid hemorrhage. The clinical and therapeutic aspects of intradural angiomas, in particular those of the cauda equina, are discussed.

Four cases of ependymoma of the filum terminale occurring in childhood are reported. The clinical, therapeutic and prognostic features seen at this age and in adults were compared.

The features of histamine-induced headache and its associated vascular responses were studied in 52 patients with different surgical lesions of the gasserian ganglion and in 12 control subjects. Certain features of headache (eg, intensity, type, and duration) were similar in patients and control subjects. However, the pain was absent on the side of the trigeminal lesion in 26 (50%) of the patients. This unilateral absence of pain was not related to the hypoesthesia that was caused by the operation, and it was associated with a decrease in vascular responses (histamine-induced facial flushing and increase in temperature) on the side operated on. These abnormalities were more prevalent in patients who had undergone thermocoagulation and presented with more severe damage of the trigeminal ganglion than in those who were subjected to trigeminal compression or glycerolization. The trigemino-vascular system seems to control headache of a vascular type and associated craniofacial vasodilatation in human subjects.

We report one case of haemangiopericytoma and two cases of meningioma whose presenting symptom was subarachnoid haemorrhage. We discuss the etiopathogenetic factors involved in this rare mode of onset in the light of the published work.

Twenty-nine cases of single cerebral metastases from renal carcinoma were the object of a retrospective and prospective study covering a period of 15 years (1975-1988). The best diagnostic means were NMR imaging with paramagnetic contrast medium and CAT scans after intravenous injection of a double dose of contrast medium. All patients underwent total surgical removal of the cerebral lesion. Radiotherapy was useful but had less influence on further reproduction than in metastases from tumors of other sites. The median survival was 28.1 months in patients who received radiotherapy and 23 months in the others. No significant difference in survival was found between the group of patients with unknown primary tumors and the other group with diagnosed primary neoplastic disease.

Thirty-four breast cancer patients with single brain metastases were reviewed: 9 underwent surgical removal only and 25 surgical removal and radiotherapy. A longer survival was seen in patients who underwent surgical removal and radiotherapy, with a mean survival of 28 months. In the 9 patients who did not receive whole brain radiotherapy, the mean survival was 15 months and there was an higher frequency of brain relapse.

Intramedullary meningioma is a rarely reported clinical entity. As far as we know, only three cases have been reported to date. We describe a further case at the cervical level and review the few published cases.

Clinical features and surgical outcome of 16 patients with dermoid or epidermoid cysts on the midline of the posterior cranial fossa are compared. Salient points in the comparison are the younger age, presence of associated malformations and better prognosis of dermoid cyst.

Solitary cerebral metastases from lung cancer are not uncommon clinical events. Whatever treatment is adopted, long-term survival is rare. Very rare indeed are reports of patients surviving the discovery of lung cancer and brain metastasis for 10 years or more. Indeed, only 16 cases have been reported to our knowledge. We report two further cases, stressing the importance of correct clinicopathological staging so that treatment may be conducted in the way most likely to ensure longer and better survival and, pending a therapeutic breakthrough, to increase the number of long-term survivors.

Cavernous angiomas represent 5 to 12% of spinal vascular malformations and usually are located at the vertebral body level with possible extension into the extradural space. The intradural intramedullary cavernoma occurs in about 3% of cases, whereas extramedullary localization is extremely rare. A new case of an intradural extramedullary cavernous angioma is reported, and the clinical, diagnostic, and therapeutic aspects of this rare malformation are analyzed.

Two cases of intracranial facial schwannoma growing from the labyrinthine portion of the facial nerve are reported. The clinical, pathological and diagnostic features and treatment of these rare lesions are discussed in the light of the most important literature on this topic.

Benign osteoblastoma is a rare tumour of bone with a predilection for the spinal column and appendicular skeleton. The skull is an unusual site. We report a case in which the lesion affected the lesser wing of the sphenoid bone and extended from the middle cranial fossa to the orbital region. We discuss the distinguishing features of the tumour, reviewing the literature, and the treatment.

Epidermoid tumors occur very rarely in the 4th ventricle. We discuss the history, clinical course, and the surgical results for seven patients. One patient had a remittal of symptoms, probably due to the emergence of the tumor from the 4th ventricle into the cisterna magna. Total removal of the capsule was possible only in the youngest patient. At present, four patients (mean follow-up, 6 years) enjoy good general and neurological health.

Dermoids of the posterior cranial fossa in children are rare. We report the clinical and pathological data on nine children with these lesions. A mean follow-up of 17.3 years after total removal confirms the excellent prognosis irrespective of whether the presenting symptom is meningitis or intracranial hypertension. A brief review of 39 published cases follows.

Intradiploic epidermoid cysts, fairly uncommon lesions in neurosurgical practice, are, as a rule, benign and slow-growing. Some attain great size, producing major neurological signs. Correct radiological assessment and complete removal of the tumour and its capsule are essential for adequate surgical treatment and good long-term prognosis. We report ten cases of intradiploic epidermoid cysts of the skull, three of which were giant lesions and one malignant, and analyze the clinicopathological and radiological features and treatment of these lesions in the light of the most important published data.