Gliomas tipo astrocytoma pilocítico "atípico recurrente" y gen B-RAF: presentación de caso clínico, discusión / Glioma type pilocytic astrocytoma "atypical recurrent" and gen BRAF: Clinical case presentation, discussion

RESUMEN El astrocitoma pilocítico (AP) es una neoplasia bien diferenciada, grado I OMS,que predomina en la infancia y es raro en la población adulta. Se reportan casos atípicos con una biología tumoral agresiva que continúan preservando la histología benigna o se transforman hacia gliomas de alto grado. Algunos estudios genéticos en esté subtipo de tumor referencian la activación de la vía MAPK/ERK a través de cambios en el gen BRAF. El objetivo del grupo es presentar un caso clínico representativo de un AP con evolución "atípica" y realizar una revisión actualizada desde la biología, genética, las posibilidades terapéuticas emergentes y exponer las controversias del tratamiento desde lo quirúrgico y las terapias complementarias.

SUMMARY The pilocytic astrocytoma (PA), formerly referred to as juvenile pilocytic astrocytomas, are WHO grade I tumors, that commonly occur during childhood and rarely in the adult population. Genetic studies of this tumor report an activation of the MAPK / ERK pathway through changes in the BRAF gene. The aim of this article is to report a series of atypical PA cases with an aggressive tumor biology that continue preserving the benign histology or transformed into high-grade gliomas, and review the biology, genetics, and emerging therapeutic possibilities for these cases. And finally expose controversies from the surgical treatment and complementary therapies.

Linfoma leptomeníngeo primario. Reporte de tres casos y revisión de la literatura / Primary leptomeningeal lymphoma. Report of three cases and review of the literature

El linfoma leptomeníngeo primario (LLMP) es una entidad con baja frecuencia de presentación, representa del 1% al 2,4% de los linfomas primarios del sistema nervioso central; las variedades histológica más observadas son el linfoma de la zona marginal tipo MALT, el linfoma B de célula grande difuso y el linfoma linfoblástico de células B. La localización y su extensión determinan las manifestaciones clínicas; en radiología se prefieren las imágenes con medios de contraste, ya que tienden a confundirse con meningiomas como la primera impresión diagnóstica y son la cirugía y los estudios de patología los que confirman el diagnóstico. La quimioterapia es la base del tratamiento en esta entidad, la radioterapia se deja como una opción secundaria. El propósito de este trabajo es presentar tres casos clínicos representativos de LLMP y las variantes por imágenes de radiología, la revisión enfocada de la literatura y el tratamiento de esta infrecuente patología.

Primary Leptomeningeal lymphmoma (PLML) is a low frequency neoplasm representing 1% to 2,4% of primary lymphomas of the central nervous system (CNS). The most frequent histological variety is the extranodal marginal zone lymphoma (MALT lymphoma), but other variants are reported such as diffuse large cell B-cell lymphoma (DLBCL). The location and extent determine the clinical manifestations. In radiology, images with contrast are preferred to difference from meningiomas which are the main differential diagnosis; nevertheless surgery and histology confirm the diagnosis. Chemotherapy is the mainstay of treatment and radiation therapy is a secondary alternative. The purpose of this paper is to present three cases of PML, the radiological variants and to conduct a focused literature review with treatment of this pathology.

Neuroradiology and histopathology in two cases of adult medulloblastoma.

Medulloblastoma (MB) is the most common central nervous system neoplasm in children and only rarely presents in the adult population. Recent molecular biology findings have characterized MB as a heterogeneous neoplasm distinguished by well-defined tumour subsets each with specific histologic and molecular features. Available immunohistochemical stains can now be used to differentiate the distinct molecular types of MB. This report analyzed the histopathologic and neuroradiologic features of two new cases of adult MB. Imaging studies in these patients revealed the morphological appearance of high-grade, well-circumscribed heterogeneous tumours with necrosis, located laterally within the posterior cranial fossa. Histopathology of resected samples demonstrated high-grade tumours (WHO grade IV) containing sheets of undifferentiated neural cells with high mitotic activity and evidence of necrosis. The histopathologic and molecular characteristics of these cases of MB are reviewed for potential applications in new molecular methods of imaging.

Primary gliosarcoma of the brain: radiologic and histopathologic features.

Gliosarcoma is a rare central nervous system (CNS) neoplasm with biphasic glial and non-glial malignant components. Here we describe the radiologic and histopathologic features observed in five cases of primary gliosarcoma. The mean age at diagnosis in the studied patients was 54.2 years; these patients were predominantly males (male:female ratio = 4:1). At diagnosis all patients had several clinical deterioration. The most common symptoms of presentation were: headache (5/5 cases), seizures (4/5 cases) and hemiparesis (1/5 cases). All the tumors were large (mean major diameter= 4.12±1.64 cm) at diagnosis as evidenced in computer tomography (CT) scans and magnetic resonance images (MRIs), with preferential involvement of the temporal lobe and frequent associated deviation of the midline structures. Other common characteristics identified on CT scans and MRIs were partial contrast medium uptake with annular pattern (5/5 cases), peripheral edema (5/5 cases), and central calcification (3/5 cases). In additional a peak of dye uptake was observed (4/5 cases) on MRI spectrometry. In the histopathology, the glial component showed malignant astrocytes, with high Ki67 (>60%) and p53 positivity; the sarcomatous components displayed pleomorphic spindle cells similarly with p53 positivity and high Ki67 (75-90%) in all cases. Dedifferentiation to pleomorphic sarcoma (two cases), fibrosarcoma (one case), leiomyosarcoma (one case) and MPNST (one case) were documented. All patients received radiotherapy/chemotherapy and had a median overall survival of ten months. The study of radiologic and histopathologic features in primary gliosarcomas of the brain is a priority to achieve early diagnosis that can be translated to better outcomes. Here we describe the radiologic and histopathologic features observed in a group of gliosarcoma patients with variable histopathologic dedifferentiation.

Desmoplastic infantile ganglioglioma with late presentation. A clinical, radiological and histopathological analysis.

Desmoplastic infantile ganglioglioma (DIG) is a rare supratentorial tumor in the central nervous system. Definitive diagnosis of this neoplasm is based on histopathologic analysis evaluating distinctive findings such as the fibroblastic differentiation. Here we present a clinical case of DIG with a long follow-up in an eight-year-old boy with a six-month history of recurrent emesis, psychomotor hyperactivity and generalized tonic-clonic seizures. Computed tomography scan and magnetic resonance imaging (MRI) showed a cystic, heterogeneous, mass on the right temporal uncus. A histopathological diagnosis of late presentation DIG was made. We documented the immunohistochemical expression of a molecular soft tissue / muscle differentiation marker (h-CaD) in addition to a low proliferative index (Ki-67) in this case. After surgical intervention, a control MRI showed changes of right frontal-temporal craniotomy and a persistent mass in the anterior and medial temporal lobe with basal extension. Further surgical intervention was performed, completely removing the tumor, which had the same characteristics. The patient is asymptomatic while receiving anticonvulsant therapy (phenytoin) with no evidence of tumor recurrence on MRI after a follow-up of five years. The low grade and soft tissue appearance in images are correlated with the histopathologic and immunohistochemical profile of this tumor, but the rarity of this tumor makes a presumptive diagnosis by images a challenge. The above-mentioned molecular markers or new ones could be used as molecular targets for molecular imaging studies to increase the probability of a pre-operative diagnosis based on molecular features through images.

Histopathological and immunohistochemical profile in anaplastic gangliogliomas

ANTECEDENTES: El ganglioglioma anaplásico (GA) es la contraparte de alto grado del ganglioglioma, un raro tumor compuesto por una mezcla de células neuronales/ganglionares y gliales. MATERIALES Y MÉTODOS: Se describe la histopatología y la inmunohistoquímica en 7casos de GA. RESULTADOS: Los casos de GA correspondieron al 2,5% de los tumores del SNC evaluados en nuestra institución. La edad media de presentación fue 25,7 años, con predominio del género masculino. La presentación más frecuente fue como convulsiones generalizadas tónico-clónicas (3/7casos), en correlación con una frecuente localización cortical/subcortical (6/7casos). Histopatológicamente todos los casos mostraron características de alto grado en las células gliales (GFAPpositivas) y ganglio/neuronales (sinaptofisina, PG-9.5, neurofilamentos, NSE y CD56-positivo), además de celularidad moderada, figuras mitóticas frecuentes y Ki-67>5%. Todos los pacientes mostraron baja supervivencia. CONCLUSIÓN: Se describe el perfil histopatológico e inmunohistoquímico en GA, el cual es constante y posee utilidad para el diagnóstico precoz de estos tumores agresivos

BACKGROUND: The anaplastic ganglioglioma (AG) is the high-grade counterpart of ganglioglioma, a rare mixed tumor composed of neuronal/ganglion and glial cells. MATERIALS AND METHODS: We describe the histopathology and immunohistochemistry in 7 cases of AG and correlate them with the clinical and radiological features. RESULTS: Our AG patients correspond to 2.5% of the central nervous system tumor patients evaluated in our institution. The mean age at presentation was 25.7 years, with a malepredominance. The most common clinical presentation was generalized tonic-clonic seizures (3/7 cases), in correlation with frequent cortical/subcortical location (6/7 cases).Histopathologically, all our cases showed high-grade features in glial (glial fibrillary acid protein-positive) and neuron-ganglion cells (synaptophysin, PGP-9.5, neurofilament, NSE and CD56-positive), as well as moderate cellularity, frequent mitotic figures and a Ki-67labeling index >5%. All our patients had poor survival. CONCLUSION: We found that a typical histopathological and immunohistochemical profile is constant and can be useful in early diagnosis of these aggressive neoplasms

Histopathological and immunohistochemical profile in anaplastic gangliogliomas.

BACKGROUND: The anaplastic ganglioglioma (AG) is the high-grade counterpart of ganglioglioma, a rare mixed tumor composed of neuronal/ganglion and glial cells. MATERIALS AND METHODS: We describe the histopathology and immunohistochemistry in 7 cases of AG and correlate them with the clinical and radiological features. RESULTS: Our AG patients correspond to 2.5% of the central nervous system tumor patients evaluated in our institution. The mean age at presentation was 25.7 years, with a male predominance. The most common clinical presentation was generalized tonic-clonic seizures (3/7 cases), in correlation with frequent cortical/subcortical location (6/7 cases). Histopathologically, all our cases showed high-grade features in glial (glial fibrillary acid protein-positive) and neuron-ganglion cells (synaptophysin, PGP-9.5, neurofilament, NSE and CD56-positive), as well as moderate cellularity, frequent mitotic figures and a Ki-67 labeling index >5%. All our patients had poor survival. CONCLUSION: We found that a typical histopathological and immunohistochemical profile is constant and can be useful in early diagnosis of these aggressive neoplasms.

Glioblastoma metastasis to parotid gland and neck lymph nodes: fine-needle aspiration cytology with histopathologic correlation.

Glioblastoma (GBM) is one of the most highly aggressive neoplasms of the central nervous system. Extra-cranial metastases in GBM are rare. Here we present the case of a 26-year-old man with extra-cranial metastasis of a frontal lobe GBM to the parotid gland, cervical lymph nodes, and bones, with initial diagnosis made by fine needle aspiration cytology (FNAC) of the parotid gland. FNAC is a reliable technique in the study of primary and secondary parotid gland neoplasms, allowing a presumptive diagnosis in difficult cases. We correlate the cytologic, histopathologic, and immunohistochemical findings in this case and discuss previous literature reports.

Changes in electromyographic results of patients with lumbar radiculopathy: a follow-up study.

OBJECTIVE: To assess the neurophysiologic changes in a group of patients with lumbar radiculopathy 5 to 12 months after their first electromyographic examination. DESIGN: A prospective group of patients with a case definition of lumbar radiculopathy was reassessed between 5 and 12 months after their first clinical, functional, imaging, and neurophysiologic evaluation. Both the lumbar paraspinals (in which the mini-mapping technique was used) and the same lower limb muscles were explored in every patient. Relevant abnormalities were (1) positive sharp waves/fibrillation potentials, (2) polyphasic motor unit potentials, and (3) large-amplitude/long-duration motor unit potentials. Patients were sorted into 5 groups based on the type and distribution of neurophysiologic abnormalities: from 0 (no abnormalities) to 4 (denervation signs in 2 lower limb muscles and paraspinals). Patients' subjective perception of any improvement or worsening of their condition was also recorded. SETTING: A referral center for neurophysiologic evaluation. PARTICIPANTS: A consecutive sample of patients (N=91) with a clinical definition of lumbar radiculopathy (lumbar pain radiating down the leg and below the knee) referred for neurophysiologic assessment was selected for an initial clinical, functional, and neurophysiologic evaluation. Patients were called for a second evaluation (between 5 and 12mo). Thirty-eight (42% of the initial sample) were willing/eligible for the second evaluation. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Changes in (1) electromyographic results; (2) patients' subjective perception of pain; and (3) quality of life, based on the Roland-Morris Questionnaire and Medical Outcomes Study 36-Item Short-Form Health Survey scores. RESULTS: Paraspinal muscles were most frequently affected. Neurophysiologic abnormalities had improved on reassessment. Clinical improvement was more significant for those patients with initially abnormal electromyographic results. CONCLUSIONS: There was clinical as well as electromyographic improvement in patients with lumbar radiculopathy within the first year of the initial diagnosis.