1/83. Medulloblastomas with extensive posttherapy neuronal maturation. Report of two cases.The authors report on two patients with classic medulloblastoma, each of whom underwent extensive therapy-associated neuronal maturation. The first patient presented at 3 months of age with hydrocephalus caused by a 5-cm tumor in the cerebellar vermis. He underwent a gross-total resection of a desmoplastic medulloblastoma. No mature elements were identified. Despite adjuvant chemotherapy, a 1.5-cm recurrent tumor developed 6 months later. Sections from the subtotally resected tumor demonstrated exclusively mature neuronal elements, ranging from neurocytes to ganglion cells. Four months later, a second recurrent tumor was resected. The specimen collected this time demonstrated classic medulloblastoma morphological characteristics. The patient was subsequently treated with radiation therapy, which seemed to have an effect; however, the tumor eventually progressed and the patient died. The second patient presented at 3 years of age with a midline medulloblastoma and was treated with subtotal resection, radiation therapy, and chemotherapy. Although the tumor remained stable on radiographic imaging, a second resection was performed 8 years later to alleviate hydrocephalus. Histological examination revealed predominantly small mature neurons with scattered ganglion cells and extensive calcification. No adjuvant therapy was given and the patient is alive and well as of his last follow-up examination. The mature neuronal neoplasms resected in both patients demonstrated negligible proliferative indices and stained appropriately with neuronal immunohistochemical markers. The smaller neuronal population resembled those of a central neurocytoma and medullocytoma/cerebellar neurocytoma. Analogous to neuroblastoma, our cases suggest that adjuvant therapy can induce extensive or complete neuronal maturation in medulloblastoma. Additional cases must be studied to determine the prognostic significance of this rare phenomenon.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
2/83. Adjuvant immunotherapy for malignant brain tumors in infants and children.Immune deficiency of immunocompetent cells or of humoral factors are essential causes of tumor growth. The authors have investigated the transfer of immunocompetent cells - allogeneic bone marrow cell transfusion and white blood cell intracranial infusion - for the treatment of 11 malignant gliomas in infants and children as an adjuvant to surgery, radiation and/or chemotherapy. Ten cases, from 3 months to 11 years, received bone marrow cell transfusion. Two medulloblastomas and 3 pontine gliomas are dead. Five cases are alive and well 37-65 months following surgery. Among these two posterior fossa neoplasms, a medulloblastoma and a glioblastoma have survived 46 and 65 months, respectively. One cerebral glioblastoma received allogeneic white blood cells infused locally into the tumor bed: it recurred 1 year following surgery, chemotherapy, and immunotherapy. Cytolysis of the tumor cells by sensitized lymphoid cells were demonstrated in this case. The role of immunotherapy should be limited at the present time to adjuvant therapy until its effect on tumor growth is statistically confirmed. The results so far are promising, and improvement of the immunological approach in treating malignant brain tumors is under way.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
3/83. herpes simplex encephalitis occurring after chemotherapy, surgery, and stereotactic radiotherapy for medulloblastoma.Reactivation of latent herpes simplex virus (HSV) in the trigeminal ganglion most commonly gives rise to recurrent herpes labialis and rarely to herpes simplex encephalitis. The mechanisms underlying reactivation of latent trigeminal HSV are complex. Here we report the case history of a 25-year-old woman who developed a fatal, bilateral necrotizing destructive temporal lobe lesion following surgical removal of a cerebellar medulloblastoma and combined radiotherapy and chemotherapy for recurrent tumor. Neuropathologic examination of the brain revealed minimal inflammatory changes, but immunohistochemistry was positive for HSV protein, and HSV deoxyribonucleic acid (DNA) was recovered from formalin-fixed paraffin-embedded brain tissue. The temporal proximity of the surgery, chemotherapy, and radiotherapy to the onset of disease suggests that these factors may have acted as triggers that precipitated conversion of latent HSV to overt HSV.- - - - - - - - - - ranking = 0.0032174392722894keywords = complex (Clic here for more details about this article) |
4/83. Large cell/anaplastic medulloblastomas and medullomyoblastomas: clinicopathological and genetic features.OBJECT: medulloblastoma is the most common malignant central nervous system neoplasm found in children. A distinct variant designated large cell/anaplastic (LC/A) medulloblastoma is characterized by frequent dissemination of cerebrospinal fluid (CSF) at presentation and a more aggressive clinical course. The authors report on their examination of the clinicopathological and genetic features of seven such cases encountered at their institution. methods: Eighty cases of medulloblastomas were reviewed and seven (8.8%) of these were believed to fit the histological and immunohistochemical criteria for LC/A medulloblastoma. In three cases (43%) either desmoplastic or classic medulloblastoma was the underlying subtype, and in two cases (28%) the LC/A tumor was found within the setting of medullomyoblastoma. fluorescence in situ hybridization was used in six of the seven cases to characterize the presence of isochromosome 17q, deletion of chromosome 22q (a deletion characteristically found in atypical teratoid/rhabdoid tumors), and c-myc amplification. The patients' clinical histories revealed CSF dissemination in all cases and lymph node metastasis in one case. Isochromosome 17q was found in five (83%) of six cases. Evidence of chromosomal gains indicated aneuploidy in three tumors (50%), and amplification of c-myc was found in three tumors (50%). No 22q deletions were encountered. CONCLUSIONS: A high percentage of LC/A medulloblastomas arise within a background of typical medulloblastomas or medullomyoblastomas. As is the case in conventional medulloblastomas, the presence of 17q is a common early tumorigenic event; however, in a significant percentage of specimens there is also evidence of aneuploidy and/or amplification of c-myc. These findings indicate that LC/A morphological characteristics reflect a more advanced tumor stage than that found in pure medulloblastomas or in typical medullomyoblastomas.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
5/83. Trilateral retinoblastoma variant indicative of the relevance of the retinoblastoma tumor-suppressor pathway to medulloblastomas in humans.Results of recent studies have led investigators to suggest that the retinoblastoma tumor-suppressor (rb) gene plays an underappreciated role in the genesis of brain tumors. Such tumors cause significant rates of mortality in children suffering from hereditary retinoblastoma. It has been assumed that the pineal gland, which is ontogenetically related to the retina, accounts for the intracranial origin of these trilateral neoplasms. To address this issue, the authors describe an unusual trilateral retinoblastoma variant. The authors provide a detailed clinicopathological correlation by describing the case of a child with bilateral retinoblastoma who died of a medulloblastoma. The intraocular and intracranial neoplasms were characterized by performing detailed imaging, histopathological, and postmortem studies. karyotype analysis and fluorescence in situ hybridization were used to define the chromosomal defect carried by the patient and members of her family. An insertion of the q12.3q21.3 segment of chromosome 13 into chromosome 18 at band q23 was identified in members of the patient's family. This translocation was unbalanced in the proband. The intraocular and cerebellar neoplasms were found to be separate primary neoplasms. Furthermore, the pineal gland was normal and the cerebellar neoplasm arose within the vermis as a medulloblastoma. Finally, the two neoplasms had different and characteristically identifiable cytolological and immunohistochemical profiles. The findings of the present study, taken together with those of recent molecular and transgenic studies, support the emerging concept that rb inactivation is not restricted to central nervous system regions of photoreceptor lineage and that inactivation of this tumor suppressor pathway may be relevant to the determination of etiological factors leading to medulloblastoma in humans.- - - - - - - - - - ranking = 6keywords = neoplasm (Clic here for more details about this article) |
6/83. Medulloblastomas in neurofibromatosis type 1. Case report and literature review.A 6-year-old girl, previously diagnosed with neurofibromatosis type 1 (NF-1) presented with ataxia and symptoms of raised intracranial pressure. Diagnostic work up disclosed a posterior fossa tumor. Histopathological study of the excised neoplasm showed a cerebellar medulloblastoma. We review the current literature and suggest that the association of medulloblastoma with NF-1 is not a chance occurrence, and that it might be pathogenically related. We propose that medulloblastoma should be added to the list of malignancies that are apt to occur in NF-1.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
7/83. Organ donor with cerebellar medulloblastoma: a case report and review of the literature.transplantation of organs and tissues procured from brain-dead organ donor (BDOD) is nowadays a common and desirable therapy for end-stag organ failure, especially kidneys, liver and heart. The majority of organs for transplantation are obtained from individuals with massive and irreversible central nervous system injury. This group of organ donors is however unsatisfactory and small according to needs. Significant percentage of multiorgan donors could be found among patients suffering from primary cerebral neoplasms as these rarely metastasize spontaneously outside the central nervous system. The paper presents the case of a 30-year-old male donor with a central nervous system tumor. Histogenesis, pathway of malignant dissemination, prognosis and the use of organ donor with cerebellar medulloblastoma are also discussed.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
8/83. Primitive neuroectodermal tumor in the cerebellopontine angle with isochromosome 17q presenting as meningioma in a woman 26 years of age.An unusual posterior fossa neoplasm in a 26-year-old woman with short history of the cerebellar symptoms is presented. CT and MR images showed the tumor within the cerebellopontine angle, suspected as meningioma. At surgery, the tumor was dura-attached and did not infiltrate the arachnoid. Histologically, the neoplasm was a small blue cell tumor with solid and microcystic pattern, consistent with primitive neuroectodermal tumor (PNET). Immunohistochemically the cells were strongly positive for NCAM and GFAP. fluorescence in situ hybridization (FISH) was performed with the cosmids G9 and F7 (flanking EWSR1/22q12 region) dna probes and dual-color spectrum-orange LSI HER-2/neu (17q11.2)/spectrum green CEP17 (17p11.1-q11.1) DNA probe. The presence of isochromosome 17q within neoplastic cells was found. The tumor was classified as a medulloblastoma. We demonstrate the utility of a multidisciplinary approach to nervous system tumor diagnosis. The clinical features together with histological, immunohistochemical, and characteristic molecular alteration allowed classification of the presented case.- - - - - - - - - - ranking = 2keywords = neoplasm (Clic here for more details about this article) |
9/83. loss of heterozygosity and p53 polymorphism Pro72Arg in a young patient with medulloblastoma.Differently from conventional primary neuroectodermal tumors (PNETs), molecular features of undifferentiated lesions have been poorly studied. medulloblastoma and PNET neoplasms showed a high incidence of loss of heterozygosity (LOH) on chromosome 17p13, in the region of tumor suppressor gene p53. Recent studies have shown a significant correlation between the presence of p53 Arg72Pro polymorphism and several undifferentiated carcinomas. We performed molecular analysis in an anaplastic tumor of posterior fossa in a patient with a constitutional maternal translocation [46,XX,t(5;19)] and a history of headache, nausea and vomiting. We identified the presence of LOH at 17p13 and Pro72Arg polymorphism in tumor DNA. These molecular findings helped us better characterize this undifferentiated tumor and led to a more aggressive therapy.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
10/83. Nevoid basal cell carcinoma syndrome: relation with desmoplastic medulloblastoma in infancy. A population-based study and review of the literature.BACKGROUND: patients with nevoid basal cell carcinoma syndrome (NBCCS) are believed to be predisposed to develop early-onset neoplasms including medulloblastomas (MB). The desmoplastic subtype of MB is associated most commonly with NBCCS. The goals of this study were to demonstrate the relation between desmoplastic MB and NBCCS and to evaluate the concomitant diagnosis of NBCCS and MB. methods: The medical records of 76 consecutive children who received surgical treatment for MB between 1970 and 2000 were studied. A review of the literature was performed based on the National Library of medicine database and bibliographies of selected articles were scanned. RESULTS: The authors reported three patients with NBCCS who received surgical treatment for an MB during infancy. The literature review identified 33 patients with NBCCS who were treated for MB at a mean age of 28 months. The desmoplastic subtype was the only histopathologic subtype of MB reported in the NBCCS population. Although patients with NBCCS are predisposed to develop multiple basal cell carcinomas and intracranial tumors in the field of irradiation, the prognosis for syndromic MBs was much better compared with the prognosis for sporadic MBs. CONCLUSIONS: patients with NBCCS have an increased risk for other malignancies, especially radiation-induced neoplasms. early diagnosis of this syndrome is important for the selection of appropriate adjuvant treatment and family genetic counseling. The authors did not advocate the use of radiotherapy as an adjuvant treatment in desmoplastic MB diagnosed in children younger than 5 years of age. They suggested that the desmoplastic subtype of MB in children younger than 2 years of age is a major diagnostic criterion for the diagnosis of NBCCS.- - - - - - - - - - ranking = 2keywords = neoplasm (Clic here for more details about this article) |
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