DCE and DSC perfusion MRI diagnostic accuracy in the follow-up of primary and metastatic intra-axial brain tumors treated by radiosurgery with cyberknife.

BACKGROUND: The differential diagnosis between radiation necrosis, tumor recurrence and tumor progression is crucial for the evaluation of treatment response and treatment planning. The appearance of treatment-induced tissue necrosis on conventional Magnetic Resonance Imaging (MRI) is similar to brain tumor recurrence and it could be difficult to differentiate the two entities on follow-up MRI examinations. Dynamic Susceptibility Contrast-enhanced (DSC) and Dynamic Contrast-Enhanced (DCE) are MRI perfusion techniques that use an exogenous, intravascular, non-diffusible gadolinium-based contrast agent. The aim of this study was to compare the diagnostic accuracy of DSC and DCE perfusion MRI in the differential diagnosis between radiation necrosis and tumor recurrence, in the follow-up of primary and metastatic intra-axial brain tumors after Stereotactic RadioSurgery (SRS) performed with CyberKnife. METHODS: A total of 72 enhancing lesions (57 brain metastases and 15 primary brain tumors) were analyzed with DCE and DSC, by means of MRI acquisition performed by 1,5 Tesla MR scanner. The statistical relationship between the diagnosis of tumor recurrence or radiation necrosis, decided according to clinicoradiologically criteria, rCBV and Ktrans was evaluated by the point-biserial correlation coefficient respectively. RESULTS: The statistical analysis showed a correlation between the diagnosis of radiation necrosis or recurrent tumor with Ktrans (rpb = 0.54, p < 0.001) and with rCBV (rpb = 0.37, p = 0.002). The ROC analysis of rCBV values demonstrated a good classification ability in differentiating radiation necrosis from tumour recurrence as well as the Ktrans. The optimal cut-off value for rCBV was k = 1.23 with 0.88 of sensitivity and 0.75 of specificity while for Ktrans was k = 28.76 with 0.89 of sensitivity and 0.97 of specificity. CONCLUSIONS: MRI perfusion techniques, particularly DCE, help in the differential diagnosis by tumor recurrence and radiation necrosis during the follow-up after radiosurgery.

Presurgical role of MRI tractography in a case of extensive cervicothoracic spinal ependymoma.

BACKGROUND: Intramedullary spinal ependymoma is a tumor, hardly characterizable with conventional magnetic resonance (MR) imaging only. MR diffusion tensor imaging (DTI) with three-dimensional fiber-tracking reconstructions allows the evaluation of the relationship between neoplasm and white matter fiber tracts, being a powerful tool in presurgical planning. We present DTI findings in a case of a young female with an extensive cervicothoracic spinal ependymoma. CASE DESCRIPTION: The patient complained of a 2-month history of acute urinary retention, weakness and numbness on the lower limbs and the upper left limb. She underwent MR imaging that showed an extensive cervicothoracic spinal mass, difficult to characterize with conventional MR sequences. DTI showed peripherally displacement of fibers, without involvement of the spinal cord, findings consistent with an ependymoma. The patient underwent surgery with a complete resection "en bloc" of the lesion, which showed clear cleavage planes, as detected by DTI. Histopathological findings confirmed the diagnosis of ependymoma. CONCLUSIONS: DTI is a useful tool in presurgical planning, helping in differentiating not infiltrating neoplasms, such as spinal ependymomas, from other infiltrative and more aggressive neoplasms, which are considered not resectable.

Perfusion computed tomography of intracranial meningiomas: In vivo correlation of cerebral blood volume and vascular permeability.

BACKGROUND: A noninvasive method to predict the grade of a meningioma would be desirable since it would anticipate information about tumour nature, recurrence and improve tumour management and outcomes. The aim of the present study was to assess the ability of perfusion computed tomography (PCT) technique in predicting the meningioma grade before surgery. Data from PCT, such as cerebral blood volume (CBV) and permeability surface (PS), were correlated with immunohistolopathological information. METHODS: Twenty-three patients with a diagnosis of intracranial meningioma underwent PCT for pre-surgical evaluation of CBV and PS. During surgery, samples from the centre and periphery of the tumour were obtained. Two correspondent regions of interest (ROIs) were drawn on CBV and PS maps. Central and peripheral CBV and PS mean values were calculated. PCT parameters were correlated to CD-34 and endoglin. RESULTS: There was a positive correlation between PS and CD-34. No correlation was found between PS values and endoglin, CBV values and CD-34 and endoglin values. CONCLUSION: Our findings suggest that PCT may support conventional morphological imaging in predicting meningioma grading before surgery.

Thoracic spinal cord cavernous angioma: a case report and review of the literature.

INTRODUCTION: Cavernous angiomas of the spinal cord are rare vascular malformations, which account for approximately 5 to 12 percent of spinal cord vascular lesions. They usually originate in the vertebrae, with occasional extension into the extradural space, and intramedullary cavernomas, even if reported in the literature, are very rare. CASE PRESENTATION: We report the case of a 34-year-old Caucasian woman affected by a thoracic intramedullary cavernous angioma. Our patient complained of 10-day history of acute dorsal pain, progressive weakness of both lower extremities, worse on the right side, a 'pins and needles' sensation in the abdominal region and bladder dysfunction. Magnetic resonance imaging showed, at D5 level, a vascular malformation, which was not documented at spinal angiography. Our patient underwent surgical treatment with total removal of the lesion and her symptoms gradually improved. A histological examination revealed the typical features of a cavernous angioma. CONCLUSIONS: Intramedullary cavernous angioma is a rare lesion that should be diagnosed early and surgically treated before rebleeding or enlargement of the lesion can occur.

Cyberknife radiosurgery for cranial plasma cell tumor.

Cranial and intracranial involvement by myelomatous disease is relatively uncommon. Furthermore, systemic manifestations of multiple myeloma are present in the majority of these cases at the time of symptom onset. The authors report the case of a patient with serial appearance of multiple intracranial plasma cell tumor localizations as the first manifestations of a multiple myeloma. The patient was treated with CyberKnife radiosurgery for a lesion localized at the clivus and sella turcica with complete local control. With such a technique, based on high-dose conformality, the tumor was centered with an ablative dose of radiation and, at the same time, with a low dose spreading to the surrounding critical structures. The radiosensitivity of plasma cell tumors renders this treatment modality particularly advantageous for their localized manifestation. A technical description of this case is provided. To our knowledge, this is the first case of successful Cyberknife radiosurgery of multifocal intracranial plasmacytoma.

Sporadic cerebral cavernous malformations: report of further mutations of CCM genes in 40 Italian patients.

Cerebral cavernous malformations (CCMs) are vascular lesions characterized by abnormally enlarged capillary cavities, affecting the central nervous system. CCMs can occur sporadically or as a familial autosomal dominant condition with incomplete penetrance and variable clinical expression attributable to mutations in three different genes: CCM1 (K-Rev interaction trapped 1 (KRIT1)), CCM2 (MGC4607), and CCM3 (PDCD10). CCMs occur as a single or multiple malformations that can lead to seizures, focal neurological deficits, hemorrhagic stroke, and headache. However, patients are frequently asymptomatic. In our previous mutation screening, performed in a cohort of 95 Italian patients, both sporadic and familial, we have identified several mutations in CCM genes, three of which in three distinct sporadic patients. In this study, representing further molecular screening of the three CCM genes, in a south Italian cohort of CCM patients enrolled by us in the last three years, we report the identification of other four new mutations in 40 sporadic patients with either single or multiple CCM.

Interleukin-8 overexpression in astrocytomas is induced by prostaglandin E2 and is associated with the transcription factors CCAAT/enhancer-binding protein-ß and CCAAT/enhancer-binding homologous protein.

BACKGROUND: The upregulation of microsomal prostaglandin E synthase-1 (mPGES-1) and the overexpression of interleukin-8 (IL-8) have been separately linked to glioma malignancy. OBJECTIVE: To evaluate (1) the correlation between the mRNA levels of IL-8, mPGES-1, and the main transcription factors (TFs) activating the IL-8 promoter in human brain tumors of different grades; (2) the role of prostaglandin E2 (PGE2) on IL-8 activation and the expression of these TFs in tumor-derived cells; and (3) the biological impact of PGE2 treatment and mPGES-1 silencing on IL-8 synthesis and tumorigenesis. METHODS: Quantitative real-time polymerase chain reaction, transfection experiments, and cell proliferation and apoptosis assays were performed. RESULTS: Regardless of histological grade, a significant positive association between IL-8 expression and mPGES-1, CCAAT/enhancer-binding protein-ß (C/EBP-ß) and C/EBP Homologous Protein (CHOP) mRNA levels was found only in astrogliomas (P < .001). The correlation was not significant in the other brain tumors. PGE2-treated astroglioma cells showed a marked upregulation of IL-8, C/EBP-ß, and CHOP, as well as increased proliferation and decreased apoptosis compared with untreated cells. mPGES-1-silenced astroglioma cells displayed decreased IL-8 synthesis, accompanied by reduced cell growth and an increased rate of apoptosis. The other brain tumor cells were unaffected either by PGE2 treatment or by mPGES-1 knockout. CONCLUSION: (1) PGE2 is responsible for IL-8 overexpression, independently of the malignancy grade, in astrogliomas only. (2) C/EBP-ß and CHOP may be involved in mediating PGE2-induced IL-8 activation in these tumors. (3) mPGES-1 inhibition may have potential as a form of adjuvant therapy for astrogliomas.

Clinical presentation of trigeminal neuralgia and the rationale of microvascular decompression.

Among the facial pain syndromes, trigeminal neuralgia has a special position for many reasons. Already described in the Romans age, the specific features of its severe symptoms, the therapeutic debate and the recent curative possibilities, make this complex pain syndrome a unique entity. The clinical onset is predominantly unilateral and is described as an electric, lancinating, focal and sharp pain. It can last seconds to minutes initially, and sometimes can last as long as 1 hour. Usually the patient is symptom-free between attacks. Later in the course of the disease, patients report dull, aching, constant pain in the same distribution as the paroxysms. The pain can be triggered by non-noxious stimuli like chewing, talking, swallowing, wind on the face, cold and light touch. Thought to be attributable to fifth cranial nerve dysfunction, the first surgical attempts aimed to interrupt nerve continuity by means of a rizothomy, with disappearance of both pain and sensory disturbances. Further investigations claimed nerve compression by vascular structures as responsible of nervous dysfunction. Hence the attempt to perform a decompression in order to relieve the symptoms and maintain physiologic nerve function. From the successful attempts of first microvascular decompression descends the now standardised and widespread technique that is commonly used today to treat trigeminal neuralgia.