1/52. Radiation-induced brain calcification: paradoxical high signal intensity in T1-weighted MR images.BACKGROUND: Irradiation to the central nervous system (CNS) in childhood is known to induce cerebral calcification after a latent period. Calcification has been generally found to show nil or a reduction in signal intensity in magnetic resonance (MR) images. However, we have studied three patients with radiation-induced brain calcification, who manifested increased signal intensity on T1-weighted MR images. METHOD: Three girls had each been diagnosed as having a suprasellar germ cell tumour and were treated with conventional fractionated radiotherapy in their childhood. In one case, chemotherapy was given prior to the CNS irradiation. FINDINGS: All three patients survived their disease, and a follow-up CT scan revealed calcification in the brain, which has shown an increased signal intensity in the T1-weighted images of MR. INTERPRETATION: Cerebral calcification may be presented as a high signal intensity in the T1-weighted MR images. This may be explained by a surface-relaxation effect by the calcium salt particle, precipitated in the brain due to radiation-induced mineralising microangiopathy.- - - - - - - - - - ranking = 1keywords = central nervous system, brain, nervous system (Clic here for more details about this article) |
2/52. Transverse sinus-tentorium splitting approach for pineal region tumors--case report.A 15-year-old boy with a large pineal region mass was admitted to our institute. The tentative diagnosis was mixed germ cell tumor. Tumor resection was carried out via a transverse sinus-tentorium splitting approach. The tumor tissue was completely resected, and no operative complication other than transient vertical gaze paresis was noted. The histological diagnosis was mixed germ cell tumor composed of mature and immature teratoma, germinoma, and embryonal carcinoma. After three courses of chemotherapy, the patient underwent external irradiation. He remained asymptomatic with no signs of recurrence 42 months after the surgery. The combination of the infratentorial supracerebellar approach and the occipital transtentorial approach provides excellent views and work space above and below the tentorial notch. Transverse sinus section is not mandatory for this approach, but sectioning of the unilateral transverse sinus and the tentorium along the rectal sinus allows retraction of the falx and the underlying brain to the opposite side. Thus, a much wider horizontal and vertical projection is obtained. This approach enables safer and more extensive tumor removal for large pineal region tumors.- - - - - - - - - - ranking = 0.10325749629105keywords = brain (Clic here for more details about this article) |
3/52. Intracranial germ cell tumours: I. Experience with platinum based chemotherapy and implications for curative chemoradiotherapy.The results of treatment with platinum based combination chemotherapy in ten patients with intracranial germ cell tumours (GCT) are presented. Two patients, treated for relapse within the central nervous system (CNS), attained partial responses of short duration. One patient with systemic relapse was successfully salvaged with chemotherapy. Seven patients received primary chemotherapy, six of whom received a 'CNS friendly' regimen consisting of vincristine, etoposide, carboplatin (VEJ) prior to craniospinal axis (CSA) irradiation. Three complete and three partial responses, and one patient with stable disease, were seen prior to irradiation. All seven patients are alive and remain disease-free at a median time of 12 months after treatment. Current treatment policy for germinomas attaining complete response to two courses of VEJ is a lowered CSA dose prescription, while non-germinomatous germ cell tumours (NGGCT) receive standard total dose CSA irradiation.- - - - - - - - - - ranking = 0.27719752596264keywords = central nervous system, nervous system (Clic here for more details about this article) |
4/52. Congenital mixed malignant germ cell tumor involving cerebrum and orbit.Congenital intracranial tumors are rare and only account for 0.5 to 1.5% of all pediatric brain tumors. teratoma is the most frequently encountered intracranial tumor at birth. Cephalomegaly and hydrocephalus are the usual clinical presentations. Advances in imaging techniques have improved diagnostic accuracy in congenital brain tumors. But the prognosis of a massive intracranial teratoma is always dismal. We report a congenital mixed malignant germ cell tumor in a male fetus at 27 weeks of gestation, with massive involvement of cerebrum and orbit. According to histological and immunohistochemical studies, the tumor was made up of predominantly immature teratoma combined with a yolk sac tumor. To our knowledge, such a combination has not been well documented in the literature.- - - - - - - - - - ranking = 0.2065149925821keywords = brain (Clic here for more details about this article) |
5/52. Primitive neuroectodermal tumors after prophylactic central nervous system irradiation in children. association with an activated K-ras gene.Three patients had supratentorial malignant brain tumors 7 to 9 years after prophylactic central nervous system (CNS) treatment for acute lymphocytic leukemia or malignant T-cell lymphoma. Therapy was administered at the age of 3 to 8 years and included cranial irradiation (total dose, 1800 to 2400 cGy) and intrathecal methotrexate. The brain tumors had histologic and immunohistochemical features of primitive neuroectodermal tumors (PNET), including neuroblastic rosettes, rhythmic arrangement of tumor cells, and immunohistochemical expression of glial, and in one patient neuronal, marker proteins. Using polymerase chain reaction-mediated dna amplification from paraffin-embedded tissues and subsequent dna sequence analysis, an activating point mutation was detected in the K-ras protooncogene in one tumor. This mutation was a G to A transition in position 2 of codon 12, substituting aspartate (GAT) for glycine (GGT). This type of mutation has not been observed before in human brain tumors, but it is frequent in radiation-induced murine lymphomas. These observations suggest that PNET can be induced after completion of the embryonal and fetal development of the human CNS. Oncogene-activating point mutations may represent a pathogenetic mechanism involved in the genesis of radiation-induced brain tumors.- - - - - - - - - - ranking = 1.7990176149774keywords = central nervous system, brain, nervous system (Clic here for more details about this article) |
6/52. Establishment and characterization of a human primitive neuroectodermal tumor cell line from the cerebral hemisphere.The primitive neuroectodermal tumors (PNET) comprise a class of malignant nervous system neoplasms that afflict children. These tumors consist of cells that are morphologically identical to the primitive neuroepithelial cells normally seen in early stages of neural embryogenesis, supporting the notion that PNET result from a disturbance in the process of normal neuronal or glial differentiation. In the central nervous system, PNET occur most commonly in the cerebellum (medulloblastomas), but only occasionally in the cerebral hemispheres. We report here the establishment and characterization of a new human cell line (PFSK) derived from a PNET from the cerebral hemisphere of a child. The growth characteristics of PFSK cells were typical of an immortalized, transformed cell line. Cytogenetic and molecular genetic studies showed that three different sublines were present. In one of these sublines, sequences from chromosome 17 had been lost during establishment in culture. Immunocytochemical studies showed that PFSK cells expressed nestin, an intermediate filament protein normally expressed by neuroepithelial stem cells during neurulation. The PFSK cells did not express antigens typically found in terminally differentiated neurons or glia, indicating that this tumor cell line might represent neuroepithelial stem cells prior to commitment to a neuronal or glial lineage.- - - - - - - - - - ranking = 0.34307068305986keywords = central nervous system, nervous system (Clic here for more details about this article) |
7/52. Melanotic neuroectodermal tumor of the skull and meninges in infancy.Three cases of melanotic neuroectodermal tumors of infancy are presented. Two were localized on the midline, involving the skull and extending subdurally. One was located on the inner aspect of the dura and developed intracranially. Two had a benign course following gross total removal. One had a malignant course, recurring locally and spreading within the brain. The difficulties of removing these tumors when they are implanted on the midline are stressed. Histological features of prognostic value are pointed out. Further support for neural crest origin of these tumors is given.- - - - - - - - - - ranking = 0.10325749629105keywords = brain (Clic here for more details about this article) |
8/52. pulmonary blastoma--a rare tumour.A 57-year-old man was found to have a tumour in the right lower lobe of the lungs, which was not classifiable by biopsy. The tumour could only be partially removed by surgical resection. The diagnosis of a pulmonary blastoma was made from the resected tissue. Clinically, rapid progress occurred with invasion in the mediastinal space and the epigastrium. In spite of radiation therapy, the patient died about 2 1/2 months after surgery of respiratory insufficiency. autopsy confirmed a pulmonary blastoma with extensive infiltration of the mediastinal space and upper abdomen as well as metastases in the regional lymph nodes, pleura, peritoneum, thyroid gland, heart and central nervous system. The present report of a pulmonary blastoma should draw attention to this extremely rare tumour. It should be included in the differential diagnosis, because the survival time can be increased if the correct diagnosis is made very early.- - - - - - - - - - ranking = 0.27719752596264keywords = central nervous system, nervous system (Clic here for more details about this article) |
9/52. A case of sudden infant death due to massive hemorrhage in primitive neuroectodermal tumor.A case of the sudden death of a 14-month-old girl due to massive hemorrhage in a primitive neuroectodermal tumor (PNET) is presented along with a review of the relevant literature. PNET is a rare, malignant brain neoplasm occurring predominantly in children.- - - - - - - - - - ranking = 0.10325749629105keywords = brain (Clic here for more details about this article) |
10/52. Sanctuary site relapse in chemotherapy-treated testicular cancer.The testis and central nervous system (CNS) may act as sanctuary sites for testicular germ cell tumours, as cytotoxic drugs penetrate these areas less well than systemic sites. We describe three patients who relapsed in the testis (one patient) or CNS (two patients) after receiving chemotherapy for responsive systemic disease. All three were asymptomatic at relapse, which was first manifest by rising tumour marker levels. These sanctuary site relapses were managed locally with surgery /- radiotherapy. Two patients were rendered disease-free; one died of progression of his local disease only. Sanctuary site tumour should be considered when relapse occurs in the setting of otherwise chemosensitive disease; local therapy may be curative.- - - - - - - - - - ranking = 0.27719752596264keywords = central nervous system, nervous system (Clic here for more details about this article) |
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