Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Malignant astrocytomas often display histopathological heterogeneity. In the present study, we have molecularly characterized different areas within 4 such tumors to determine whether the tissue heterogeneity can be explained by differences in DNA constitution. Two tumors contained low grade areas, and the other 2 had areas with satellitosis. The tumors were examined for loss of heterozygosity with markers from chromosomes 9p, 10, and 17p and for amplification of the epidermal growth factor receptor gene. In each case, the high grade portion of the tumor displayed at least one of these structural alterations. However, identical alterations were found in the associated low grade or satellitosis areas of each tumor. Our data suggest that: (a) genetic alterations associated with tumor progression already occur in histopathologically low grade areas of high grade astrocytoma; (b) satellitosis associated with a high grade astrocytoma has to be considered as part of that tumor; and (c) tissue heterogeneity within a high grade astrocytoma is not a consequence of differences in DNA constitution at the loci that were examined.
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PMID:Molecular characterization of areas with low grade tumor or satellitosis in human malignant astrocytomas. 131 34

Gliomas that arise in the tectal and periaqueductal region of the mesencephalon usually present with hydrocephalus secondary to occlusion of the aqueduct of Sylvius. A review of 486 brain tumors in children treated during a 5-year period revealed 6 children with gliomas of the tectal plate. The 6 children were shunted for hydrocephalus, presumed secondary to aqueductal stenosis, prior to establishing the diagnosis of tectal plate glioma. No abnormalities were noted on the initial, uncontrasted computed tomography (CT) scans. The tumors are isodense without contrast enhancement which makes the CT diagnosis difficult. Magnetic resonance imaging (MRI) is diagnostic and demonstrates the characteristic enlargement of the tectum with increased density on T2 images. T1 density and gadolinium enhancement are variable. Pathological confirmation was obtained by open biopsy in 2 patients, a stereotaxic biopsy was performed on 2 children; 2 children were not biopsied. The tumor histology obtained was that of pilocytic astrocytoma. Two patients were treated with radiation therapy at the time of diagnosis. One child was followed closely and subsequently irradiated after tumor progression. All patients in this series are alive and functioning adequately 2-10 years after the onset of symptoms.
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PMID:Gliomas of the tectum and periaqueductal region of the mesencephalon. 182 88

Between March, 1983, and February, 1989, 19 infants or children with chiasmal/hypothalamic gliomas were treated with chemotherapy after either surgical or radiological diagnosis. The patients ranged in age from 15 weeks to 15.6 years (median 3.2 years) at the start of therapy. Twelve patients were treated immediately after diagnosis because of progressive symptoms, and seven received chemotherapy after either radiographic progression or clinical deterioration, including progressive visual loss or intracranial hypertension. Based on biopsy results, seven of these tumors were classified as juvenile pilocytic astrocytomas, two as astrocytomas, two as highly anaplastic astrocytomas, and one as a subependymal giant-cell astrocytoma. There was associated neurofibromatosis in four patients. The two initial patients were treated with either actinomycin D and vincristine or 5-fluorouracil, hydroxyurea, and 6-thioguanine. The remaining patients received nitrosourea-based therapy; 15 evaluable patients were treated with a five-drug regimen that included 6-thioguanine, procarbazine, dibromodulcitol, 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU), and vincristine and one received 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and 5-fluorouracil. Fifteen of the 18 evaluable patients initially managed with chemotherapy either responded to therapy or their condition stabilized. Median time to tumor progression has not been reached at a median follow-up period of 79 weeks (range 6.6 to 303 weeks), and no tumor-related death has occurred with a median follow-up period of 79 weeks (range 18 to 322 weeks) from the initiation of therapy. The four patients who failed therapy or whose disease progressed after chemotherapy were treated satisfactorily with radiation therapy. Initial improvement or stabilization of visual function was obtained in 16 patients. Endocrine function remained stable in all patients during treatment, although three patients required pharmacological treatment for endocrinopathy that was present at diagnosis. These preliminary results suggest that nitrosourea-based cytotoxic regimens are useful for the initial treatment of children with chiasmal/hypothalamic gliomas, and allow potentially harmful radiation therapy to be deferred until progression of disease.
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PMID:Management of chiasmal and hypothalamic gliomas of infancy and childhood with chemotherapy. 190 97

Sixteen patients who developed CT or MRI scan evidence of recurrent diffuse astrocytoma after radiation therapy and nitrosourea-containing chemotherapy received ifosfamide (2500 mg/m2/day for 3 consecutive days) and mesna (500 mg/m2/dose, 5 doses/day for 3 consecutive days). Toxicity consisted primarily of leukopenia in that 60 percent of patients developed leukocyte nadirs less than 1500/mcL. Excessive somnolence occurred in three patients and may have contributed to a case of fatal pneumonia in one patient but was reversible in the other two. No patient had CT or MRI scan evidence of tumor regression. One patient remains stable at 11.3 + months, but all other patients developed evidence of progressive disease less than 6 months from initiation of therapy. The median times to tumor progression and death were 2.0 and 4.8 months, respectively. In conclusion, while ifosfamide and mesna can be given safely at this dose and schedule, there is no evidence of antitumor effect. The degree of leukopenia observed likely would prevent further dose escalation of ifosfamide or addition of other myelosuppressive agents without additional means of bone marrow support in this population of patients.
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PMID:Phase II study of ifosfamide with mesna in adult patients with recurrent diffuse astrocytoma. 190 6

Human astrocytoma cells were cultured and inoculated into the rat brain. From the pre-clinical to the terminal state, tumour growth was monitored by in vivo MR imaging and by localized water-suppressed 1H spectroscopy (0.12-0.15 cm3 volumes) and spectroscopic imaging (0.01 cm3 voxels) employing the ACE localization technique. The MR experiments were conducted completely non-invasively, leaving the scalp intact. Brain spectra were obtained, showing distinct resonances for more than five different brain metabolites; they were not contaminated with lipid signals because of the adequate localization. Tumour progression, monitored in a selected volume of interest, was reflected in the corresponding spectra by decreasing intensities for resonances of N-acetyl aspartate and (phospho)creatine and increasing intensities for resonances of choline compounds and lactate. From spectroscopic imaging experiments metabolic heterogeneity could be deduced within the tumorous region. At particular times during tumour development spectra were obtained greatly resembling localized 1H MR spectra obtained from patients with astrocytomas by the use of similar localization methods. This emphasizes the relevance of animal model study for the evaluation of MR spectroscopic investigations in human brain tumour diagnosis and therapy evaluation.
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PMID:Non-invasive in vivo localized 1H spectroscopy of human astrocytoma implanted in rat brain: regional differences followed in time. 191 Oct 99

The effects of radiation therapy on 29 brain stem gliomas in childhood were evaluated by computed tomography (CT). The patients received radiation of 2 Gy/day as a single fraction, 5 day a week with a total dose of 40 to 60 Gy. Initial CT findings of brain stem gliomas were divided into two types: diffuse and localized. Of 29 children, 5 had localized and 24 had diffuse tumor. Histological diagnoses were available for 18 patients, 4 with localized and 14 with diffuse tumor. All of the localized tumors were astrocytomas and diffuse tumors included 13 anaplastic gliomas (glioblastomas), 3 anaplastic astrocytomas, and one astrocytoma. Complete response or partial response to radiation therapy was observed on CT in 100% (5/5) of the localized tumors and 46% (11/13) of the diffuse tumors at the first evaluation. Contrary to expectation, low-grade gliomas responded much better to radiation therapy than high-grade gliomas. The response rates were 80% (4/5) in astrocytoma, 67% (2/3) in anaplastic astrocytoma, and 38% (5/13) in anaplastic glioma. In the follow-up CT after radiation therapy, a delayed effect was observed in only one of the 24 diffuse tumors. Nine of 10 children who had a re-irradiation following the recurrence experienced very little benefit. None of the patients with localized tumors have shown evidence of tumor progression or recurrence, and the quality of their life has been excellent. On the other hand, all of the patients with diffuse tumor died within 20 months after initial treatment. The results of this study suggest that radiation therapy is beneficial for localized tumors but not for diffuse tumors, and new treatments need to be developed for diffuse tumors.
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PMID:[Evaluation of radiation therapy in pediatric brain stem glioma by computed tomography: CT findings and tumor response to radiotherapy]. 202 68

The purpose of this study was to determine the efficacy of 24-hour concomitant infusions of etoposide (100 mg/m2/day, days 1-3) and cisplatin (45 mg/m2/day, days 2-3) in the treatment of patients with recurrent astrocytoma. All 36 patients entered on this trial had histologic proof of astrocytoma with CT scan evidence of tumor progression despite prior radiotherapy and nitrosourea chemotherapy. At initial diagnosis, three patients had low-grade astrocytoma, but 33 (92%) had high-grade astrocytomas. ECOG performance score was 0-1 in 20 patients and 2-3 in 16 patients. The median age of all patients was 45.5 years. Dose-limiting toxicity was myelosuppression with median leukocyte and platelet nadirs of 2,150/mcL and 56,500/mcL respectively. One life-threatening infection occurred, but there were no treatment-related deaths. Vomiting occurred in 78% of patients, but was severe in only 6%. Peripheral neuropathy occurred in 28% but was severe in only 6%. Six patients (17%; 1 CR, 5 REGR) responded to therapy with median time to progression of 6.0 months (range 1.5-17.7 months). Five additional patients (14%) remained stable greater than 6 months and 1 has not progressed at 17.0+ months. Median time to progression and survival in all patients were 2.7 and 5.8 months, respectively. In conclusion, etoposide and cisplatin at this dose and schedule have limited activity in the treatment of recurrent high grade astrocytomas, although durable responses or periods of stability occurred in some patients. Considering the extent of myelosuppression, near maximal doses of the drugs were given.
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PMID:Phase II evaluation of infusional etoposide and cisplatin in patients with recurrent astrocytoma. 208 39

Our previous investigations correlated the degree of cytogenetic and immunophenotypic heterogeneity of cultured normal glia, astrocytomas and malignant gliomas. The possible significance was suggested by the statistical correlation of individual antigens with diagnosis and patient survival. The present study has established the patterns of covariation of titers of monoclonal antibody reactivity with a panel of cell surface antigens among normal glia (8), astrocytomas (4), anaplastic astrocytomas (12), mixed malignant gliomas (8) and glioblastomas (21). A mean aggregate titer across 43 antigens was computed for each culture and then subtracted from the observed individual titers. Factor analysis was performed to determine a small number of Factors, derived as the weighted average of the 43 mean-adjusted antigens, which accounted for a significant proportion of the covariation of immunophenotypic expression in the sample of 53 cultures. Clusters of antigens were found to independently segregate in their deviation from the aggregate phenotype. Adjusting for age and diagnosis, Factors 1 and 4 correlated with patient survival among recurrent and primary neoplasms, respectively. Factor 2 additionally discriminated between primary and recurrent gliomas. Factor 3 was associated with age at diagnosis. Factors 1 and 2 correlated with the histopathologic grade of glial tumor. Scatter plots of Factor 1 vs. 2 revealed the minimal immunophenotypic diversity of the normal glia. Astrocytomas were similar but not identical. Progressive divergence was evident between the immunophenotypes of anaplastic astrocytomas, mixed gliomas and glioblastomas. These data suggest that qualitative and quantitative differences in antigenic heterogeneity may identify stages in glial tumor progression.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Factor analysis of the immunophenotypes of astrocytomas and malignant gliomas: correlations with tumor grade and patient survival. 208 40

Quantitative determination of human glioma-associated antigen in cerebrospinal fluids (CSFs) obtained from 66 patients with a variety of neurological diseases was performed by solid-phase radioimmunoassay with a monoclonal antibody (G-22). In this system, the minimum detectable amount of the antigen in the CSF was 8 ng/ml. It was demonstrated that CSF diagnosis of glioblastoma might be possible in the case of small tumors with a diameter of less than 2 cm. CSFs obtained from all 18 patients with glioma were positive and the level varied from 11.2 to 186.1 ng/ml. The antigen level in the cystic fluid of the tumor was higher than that in CSF. There was a tendency for the antigen level in CSF to be correlated with the tumor size and the type of histology. The malignant types of glioblastoma or medulloblastoma showed higher levels than the benign type of ependymoma and astrocytoma. Most types of non-gliomatous brain tumor were negative except immature teratoma, meningioma with central neurofibromatosis, and metastatic brain tumor from lung cancer. We also noted that tumor progression or regression of malignant glioma could be predicted by the monitoring of the antigen in the CSF.
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PMID:Radioimmunoassay of glioma-associated antigen in cerebrospinal fluid and its usefulness for the diagnosis and monitoring of human glioma. 191 50

The authors believe that the preferred treatment for pineal region tumors in children requires definitive surgery with a histological diagnosis and that a conservative approach consisting of shunting and radiation therapy no longer seems to be appropriate. The results are reported of a retrospective review of the presentation, treatment, and outcome of 36 children under the age of 18 years treated between 1974 and 1986. Eleven children had germinomas (two-cell type), seven had astrocytomas, and the remaining 18 had 15 histologically different tumor types. Surgery was performed on 30 patients; there were no deaths, but a 10% rate of persistent morbidity was found. The median follow-up period was 4 years. Nine (82%) of 11 patients with germinomas are alive without evidence of recurrence; one child died from recurrent tumor in the pineal region and another is presently being treated for recurrent tumor of the spinal cord. Six (86%) of the seven patients with astrocytoma are well after biopsy and radiation therapy. Of the remaining 18 children, five (28%) died from tumor progression. The cerebrospinal fluid (CSF) tumor markers alpha-fetoprotein and beta-human chorionic gonadotropin were helpful in determining the presence of malignant germ-cell tumors, particularly those with a poor prognosis. Magnetic resonance imaging was useful for diagnosis and for planning the operative approach. Magnetic resonance images showed the presence of pineal region tumors in four children with hydrocephalus who had no evidence of tumor on computerized tomography scans. Because the great variety of tumor types found in the pineal region must be treated in different ways and because improved microsurgical and stereotaxic surgical techniques have made mortality and morbidity rates acceptably low, a biopsy diagnosis should be obtained in all patients. Preoperative assessment of CSF tumor markers and cytology is useful for the identification of patients who have a poor prognosis.
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PMID:Pineal region tumors in children. 245 17


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