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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The sarcomatous component of gliosarcomas is thought by many to originate from the vascular proliferation seen in glioblastoma multiforme and has, therefore, been assumed to be endothelial. Immunohistochemical staining of four gliosarcomas has led us to an alternate theory. Pathologically all four tumors were composed of at least two cell types; the first had a stellate, glial appearance and the second was either spindled or polygonal in shape. Polygonal cells were associated with glomeruloid vascular structures in some areas. Both components of each neoplasm were cytologically malignant. Glial fibrillary acidic protein and S-100 antibodies stained most of the glial-appearing cells and some of the spindled cells, but not the polygonal cells. Muscle specific alpha-actin and smooth muscle specific alpha-actin antibodies stained only the malignant spindled and polygonal cells and normal vascular smooth muscle. Ulex europaeus agglutinin I and anti-factor VIII/related antigen antibody stained only cells lining vascular lumina. The staining results suggest that the malignant mesenchymal component of these tumors is of smooth muscle origin. Having demonstrated elsewhere that glomeruloid vascular structures of glioblastoma multiforme contain smooth muscle cells, we propose here that gliosarcomas can represent one end of the spectrum of glioma-induced vascular smooth muscle proliferation.
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PMID:Smooth muscle can comprise the sarcomatous component of gliosarcomas. 138 14

Pleomorphic xanthoastrocytomas (PXA) are classically supratentorial, peripherally located, well-circumscribed, partially cystic neoplasms, which can enhance on CT following the administration of intravenous contrast agents. Focal calcification may also be seen. Although the CT appearance has been described, we report the MR findings in two cases of histologically documented temporal lobe PXA. The two well-circumscribed lesions were predominantly cystic and both contained a Gd-DTPA enhancing mural nodule. The latter was isointense with gray matter on T1-weighted images and hyperintense on T2-weighted scans. Minimal surrounding edema was present. Histologically, PXA may be confused with glioblastoma multiforme (GBM) due to the pronounced cellular pleomorphism. Because of their potentially more indolent behavior compared with GBM, it is important to recognize the gross morphologic characteristics of this rare tumor on MR. The MR pattern of a cystic lesion with enhancing mural nodule is characteristic of PXA, but not diagnostic, and other lower grade gliomas such as ganglioglioma and pilocytic astrocytoma need to be considered. The MR and CT appearance of PXA can provide critical information for the pathologist, especially when only a small amount of tissue is obtained for histologic evaluation.
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PMID:MRI of temporal lobe pleomorphic xanthoastrocytoma. 138 98

A retrospective review of the records of the Division of Neuropathology at the New York University Medical Center between 1977 and 1988 revealed 53 cases of adult supratentorial astrocytomas. Fifty were fibrillary, and three were gemistocytic. Two additional patients had pilocytic tumors and were not included in the study. The majority of patients had either a subtotal (64%) or gross total resection (19%). Biopsy (17%) was performed for deep-seated lesions and for those lesions confined to eloquent cortex. Forty-eight patients (91%) received postoperative radiation therapy. The median survival was 7 1/4 years with a 5-year survival of 64%. Multivariate regression analysis demonstrated that the most important prognosticators for improved survival were young age, absence of contrast enhancement of the original tumor on computed tomography (CT) and the performance status of the patient. Patients with hemispheric tumors died from dedifferentiation into an anaplastic astrocytoma or a glioblastoma multiforme, with a median time to recurrence of 4.5 years from the original surgery. Survival from the time of recurrence was 12 months. Subsequent operations confirmed progression towards malignancy in six of seven (86%) recurrent tumors. CT contrast enhancement of the original tumor was associated with a 6.8-fold increase in risk for later recurrence. Patients with thalamic tumors (six patients) had a poor prognosis with a median survival of less than 2 years. A review of their CT scans suggest that four died of progressive low-grade disease; however, confirmatory autopsy data were available for only one patient. This study supports others that have shown improved survival for adult patients with astrocytomas treated in the CT era.
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PMID:Treatment and survival of low-grade astrocytoma in adults--1977-1988. 140 48

We wondered whether second line chemotherapy in recurrent GBM patients might be useful for debulking the tumor mass and improving patient performance status to prepare the way for second surgical intervention. We have treated 18 recurrent glioma patients with high dose methotrexate (HDMTX) plus 5-fluorouracil (5FU). 5 Patients were responders, 6 had stable disease, and 7 disease progression. 5 patients, 3 PRs and 2 SDs, underwent a second operation after two chemotherapy cycles. Disease progression resumed at 11.5 +/- 7 weeks in the non reoperated patients, and at 32.6 +/- 9.3 weeks in the reoperated group from initiation of neoadjuvant treatment. Survival time in reoperated patients was 82.6 weeks. Although our experience with this policy is still limited, we believe that reoperation in selected recurrent GBM patients can be worthwhile.
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PMID:Neoadjuvant chemotherapy in the treatment of recurrent glioblastomas (GBM). 142 92

A total of 307 adult patients with glioma were treated with high-activity removable iodine-125 interstitial brain implants at the University of California at San Francisco from December 1979 to June 1990. Recurrent gliomas underwent brain implant alone whereas previously untreated (primary) tumors underwent brain implant boost after external beam radiotherapy. Of these patients, 106 had primary glioblastoma multiforme, 68 had primary non-glioblastoma glioma, 66 had recurrent glioblastoma multiforme and 67 had recurrent nonglioblastoma glioma. Median follow-up for living patients was 143 weeks. Median survival from diagnosis for primary glioblastoma multiforme and high and low grade nonglioblastoma glioma was 88 weeks, 142 weeks, and 226 weeks, respectively. Median survival measured from the date of implant for recurrent glioblastoma multiforme and high and low grade nonglioblastoma glioma was 49 weeks, 52 weeks, and 81 weeks, respectively. Ninety-two percent of patients had no toxicity or transient acute side effects. Severe acute toxicity was seen in 6% of patients, life threatening acute toxicity in 1% of patients, and fatal toxicity in less than 1% of patients. Forty percent of patients with malignant glioma underwent reoperation at a median of 33 weeks after brain implant, with tumor found in 95% of specimens at reoperation. This large experience demonstrates that interstitial implant is well-tolerated and prolongs survival in patients with primary and recurrent glioblastoma multiforme, as evidenced by the 3-year survival rates of 22% and 15%, respectively.
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PMID:High activity iodine-125 interstitial implant for gliomas. 142 79

Although interstitial brachytherapy appears to be effective in treating recurrent malignant gliomas, it has been studied less extensively in patients with newly diagnosed tumors. To examine the effect of this treatment when used at the time of primary diagnosis, we retrospectively reviewed the records of 88 patients who received temporary interstitial implants of 125I for newly diagnosed malignant gliomas. This brachytherapy was preceded by a course of external radiation therapy and followed, in some cases, by chemotherapy. The median duration of survival after the beginning of external radiation therapy was 87 weeks in patients with glioblastoma multiforme and 160 weeks in those with anaplastic gliomas. In 46% of patients with glioblastoma multiforme and 56% of those with anaplastic gliomas, a second operation was necessary to remove symptomatic radiation necrosis, recurrent tumor, or both. Our results support the conclusion that interstitial brachytherapy used at the primary diagnosis lengthens survival in selected patients with glioblastoma multiforme. However, the toxicity is significant in terms of the need for surgical resection of symptomatic necrosis. In patients with anaplastic gliomas, the toxicity associated with the treatment probably outweighs its advantages.
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PMID:Interstitial brachytherapy for newly diagnosed patients with malignant gliomas: the UCSF experience. 142 80

Between February 1984 and September 1990, 60 patients with brainstem gliomas were treated with hyperfractionated radiotherapy in the Department of Radiation Oncology at the University of California, San Francisco. Forty-one children (< or = 18 years) and 19 adults were treated with 100 cGy twice daily with 4-8 hr between doses. Thirty-one patients (21 children and 10 adults) received total doses of 66-72 Gy and 29 patients (20 children and nine adults) received 74-78 Gy. Median follow-up was 208 weeks for all patients (214 weeks for children, 157 weeks for adults). Twenty-three patients (14 children and nine adults) were alive at the time of analysis, surviving 59-359 weeks following treatment. Median actuarial survival was 73.6 weeks overall (72 weeks for children, 190 weeks for adults; p = 0.43). Survival at 12 and 24 months was 65% and 38%, respectively (63% and 32%, for children; 68% and 53% for adults). All patients had pretreatment magnetic resonance imaging by which tumors were classified as either focal or diffuse. No significant pretreatment prognostic factors for adults were identified. In children, significant favorable prognostic factors on univariate analysis were older age (p = 0.001), tumor location in thalamus or midbrain (p = 0.002), focal appearance on MRI scan (p < 0.001) and duration of symptoms > 2 months prior to treatment (p < 0.001). Thirty-five patients had tumor biopsies, leading to a diagnosis in 33 (22 children and 11 adults). Children with moderately anaplastic astrocytomas survived significantly longer than those with glioblastoma multiforme or unbiopsied tumors (p < 0.001). Only duration of symptoms > 2 months remained significant as a favorable prognostic indicator for children on multivariate analysis (p < 0.001). Survival was not significantly different for patients receiving < or = 72 Gy and those receiving > 72 Gy (p = 0.18). No subgroup of patients showed significantly better survival with the higher dose. These findings indicate that hyperfractionated radiotherapy is effective treatment for adults and a subgroup of better prognosis children with brainstem gliomas. There is a subgroup of pediatric patients with extremely poor prognosis for whom even this aggressive treatment does little to extend survival. We conclude that there is no benefit to increasing total dose above 72 Gy for any of the groups analyzed.
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PMID:Hyperfractionated radiation therapy for gliomas of the brainstem in children and in adults. 142 81

A Phase I study of interstitial thermoradiotherapy for high-grade supratentorial gliomas has been completed. The objective of this trial was to test the feasibility and toxicity of hyperthermia induced by ferromagnetic implants in the treatment of intracranial tumors. The patient population consisted of 16 males and 12 females, with a median age of 44 years and a median Karnofsky score of 90. Nine patients had anaplastic astrocytoma while 19 had glioblastoma multiforme. Twenty two patients were treated at the time of their initial diagnosis with a course of external beam radiotherapy (median dose 48.4 Gy) followed by an interstitial implant with Ir-192 (median dose 32.7 Gy). Six patients with recurrent tumors received only an interstitial implant (median dose 40 Gy). Median implant volume for all patients was 55.8 cc and median number of treatment catheters implanted per tumor was eighteen. A 60-minute hyperthermia treatment was given through these catheters just before and right after completion of brachytherapy. Time-averaged temperatures of all treatments were computed for sensors located within the core of (> 5 mm from edge of implant), and at the periphery of the implant (outer 5 mm). The percentage of sensors achieving an average temperature > 42 degrees C was 61% and 35%, respectively. Hyperthermia was generally well tolerated; however, there have been 11 minor toxicities, which resolved with conservative management, and one episode of massive edema resulting in the death of a patient. In addition, there were three major complications associated with the surgical implantation of the catheters. Preliminary survival analysis shows that 16 of the 28 patients have died, with a median survival of 20.6 months from diagnosis. We conclude that interstitial hyperthermia of brain tumors with ferromagnetic implants is feasible and carries significant but acceptable morbidity given the extremely poor prognosis of this patient population.
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PMID:Treatment of malignant gliomas with interstitial irradiation and hyperthermia. 142 88

Beginning in 1986, using software to optimize radiation dosimetry, we have stereotactically placed removable catheters containing high activity I-125 sources into malignant gliomas in 56 patients. There were 32 men and 24 women, age 7 to 73. Forty-four had glioblastoma multiforme, and 12 anaplastic astrocytoma. Mean Karnofsky performance score was 75, range 50-100. Twenty patients (all with glioblastoma) were implanted after resection before further therapy, and 36 were implanted at recurrence following resection, external irradiation and chemotherapy. Six thousand cGy was delivered to the enhancing tumor contour on CT scan. Mean dose rate was 37 cGy/hr. Mean tumor volume was 41 cc, range 5-187 cc. Mean volume of brain that received 60 cGy was 67 cc, range 11-184 cc. Of 20 patients treated after resection alone, 8 are alive, 3-43 months after implantation; median survival is 22 months. Of 36 patients treated at recurrence, 14 are alive, 0-19 months after implantation; median survival is 10 months. The most common side effect of the procedure, which occurred in five patients, was catheter misplacement. Twenty-four patients (43%) required 27 reoperations, 1-25 months after implantation. In 25 pathologic specimens available for review, microscopic tumor foci with substantial radiation necrosis were found in 18, radiation necrosis only was noted in 5, and glioma alone was seen in 2.
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PMID:Interstitial irradiation of malignant gliomas. 144 65

Malignant gliomas are characteristically surrounded by marked gliosis. To assess whether glioma-derived products contribute to the proliferation of astrocytes, a feature of the gliosis response, we evaluated the influence of culture supernatants from malignant human glioma lines and tumor cyst fluids collected from two patients with glioblastoma multiforme on the proliferation of non-transformed adult human astrocytes. Both the culture supernatants and cyst fluids significantly increased DNA synthesis in astrocytes as assessed by a double immunofluorescence glial fibrillary acidic protein-bromodeoxyuridine technique. The net proliferative effect mediated by glioma cell line supernatants was tumor growth phase-dependent, being preferentially expressed during the logarithmic phase of glioma cell growth. Specific growth factor molecules and cytokines known to be secreted by gliomas (epidermal growth factor, fibroblast growth factor, platelet-derived growth factor, transforming growth factor-beta, interleukin-6, and tumor necrosis factor-alpha) could not reproduce the mitogenic effects of the glioma-derived soluble factors. Cytokines which can induce DNA synthesis by adult human astrocytes in vitro, gamma-interferon and interleukin-1, were not detected in the culture supernatant of glioma lines used in this study. In conjunction with the documented effects of glioma products on endothelial and lymphoid cells, the current study suggests that soluble glioma products can contribute to the production of surrounding gliosis observed in vivo.
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PMID:Malignant glioma-derived soluble factors regulate proliferation of normal adult human astrocytes. 151 71


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