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991.
Surgical Outcome and Prognostic Factors of Spinal Intramedullary Ependymomas in Adults 总被引:13,自引:0,他引:13
The goal of treatment for spinal ependymoma is complete removal with minimal postoperative neurological deficit. The authors correlated the results of surgical management for spinal cord ependymoma with the rate of postoperative disease progression and the prognostic factors. Thirty-one cases of spinal ependymomas, surgically treated between 1979 and 1998, were retrospectively analyzed. The authors reviewed clinical features, radiological characteristics and operative findings for the surgical outcome analysis. Thirty-five percent of patients with preoperative Nuricks grade better than grade 4 showed improvement in functional status, whereas no improvement was observed in patients with preoperatively poorer functional status (P=0.05). The proportion of complete surgical removals was influenced by tumor location (40% in cases around the conus versus 97% in other regions, P=0.003) and histology (42% in the myxopapillary subtype versus 97% in the non-myxopapillary subtype, P=0.001). Disease progression was observed in six cases, the mean progression free interval after surgical removal was 83 months and the 5-year progression free rate was 70%. Disease progression was found in two out of 23 cases from the complete removal group and in four out of eight cases from the incomplete removal group (P=0.008). In the aspect of disease progression, the only statistically significant factor by multivariate analysis was the surgical extent of removal (P=0.010). Of those patients where there was incomplete removal, radiation therapy lead to improved clinical results, which were not statistically significant (P=0.27). In the surgical treatment of spinal cord ependymoma, preoperative functional status and the extent of removal were the significant prognostic factors influencing postoperative outcome. Early diagnosis is vital and complete removal of the tumor should be attempted in all surgical treatment of spinal ependymoma. 相似文献
992.
Urbach H Scheffler B Heinrichsmeier T von Oertzen J Kral T Wellmer J Schramm J Wiestler OD Blümcke I 《Epilepsia》2002,43(1):33-40
BACKGROUND AND PURPOSE: Focal cortical dysplasia of Taylor's balloon-cell type (FCD-BC) are a frequent cause of pharmacoresistant epilepsy in young patients. In order to characterize FCD-BC, we coupled MRI and histopathology, and analyzed the clinical outcome following epilepsy surgery. METHODS: From an epilepsy data bank with 547 histological specimens, 17 FCD-BC were re-evaluated of which high resolution MRI was available. Five additional FCD-BC were prospectively identified by MRI. Histopathological and immunohistochemical features were related to MRI. Outcome following lesionectomy was analyzed as determined on routine examinations 3, 6 and 12 months following surgery. RESULTS: All but one lesion were located outside the temporal lobe. A markedly hyperintense funnel-shaped subcortical zone tapering towards the lateral ventricle was the characteristic finding on FLAIR MRI. Histopathologically, the subcortical zone of the FCD-BC displayed hypomyelinated white matter with radially oriented balloon cells and gliosis. Dysplastic neurons were found in the adjacent, disorganized cortex. All patients with complete lesionectomy were seizure free one year following surgery. CONCLUSION: Focal cortical dysplasias of Taylor's balloon-cell type (FCD-BC) have characteristic MRI and histopathological findings. MRI recognition is important, since outcome following resective surgery is favorable. 相似文献
993.
Photoimmunosuppression 总被引:3,自引:0,他引:3
Schwarz T 《Photodermatology, photoimmunology & photomedicine》2002,18(3):141-145
Ultraviolet (UV) radiation can exert a variety of biological effects, including induction of skin cancer, premature skin ageing and inhibition of the immune system. The immunosuppressive properties of UV radiation are of major biological relevance since suppression of the immune system by UV radiation is not only responsible for the exacerbation of infectious diseases following UV exposure, but also contributes to the induction of skin cancer. Hence, understanding of the mechanisms by which UV radiation compromises the immune system is of primary importance. UV radiation suppresses the immune system in multiple ways. It inhibits antigen presentation, stimulates the release of immunosuppressive cytokines and induces the generation of lymphocytes of the suppressor subtype. In the following, some of the basic mechanisms underlying UV-induced immunosuppression will be discussed. 相似文献
994.
BACKGROUND: Punta Arenas, Chile, the southernmost city in the world (53 degrees S), with a population of 154,000, is located near the Antarctic ozone hole (AOH) and has been regularly affected by high levels of ultraviolet-B (UV-B) radiation each spring for the last 20 years. Large increases in UV-B associated with the AOH have been measured with increases in UV-B at 297 nm of up to 38 times those of similar days with normal ozone. Recently we reported significant increases in sunburns during the spring of 1999 on days with low ozone because of the AOH. METHODS: A surveillance of skin cancers occurring from 1987 to 2000 was performed. Age, sex, location, type of skin cancer and skin phototype were recorded. A Brewer Spectrophotometer was used in order to obtain in situ measurements of ozone and UV-B. Total Ozone Mapping Spectrometer (TOMS) data from National Aeronautics and Space Administration (NASA) was used in order to establish pre-ozone hole climatology. RESULTS: Ozone levels as low as 145 DU (Dobson Units) were recorded, a 56% decrease in ozone, and UV-B levels up to 4.947 J/m2. These levels are close to summertime levels at mid latitudes. For the 14-year period--from 1987 to 2000--173 cases of skin cancer were diagnosed, 65 during the first 7 years, 108 during the second, an increase of 66%. Cutaneous malignant melanoma (CMM), 19% of the cases, increased by 56%, raising the rate from 1.22 to 1.91 per 100,000. Non-melanoma skin cancer (NMSC), 81% of the total, increased the rate from 5.43 to 7.94 per 100 000 (P < 0.05), a 46% increase. Patients with CMM and NMSC had skin phototypes I-II in 59% and 54% of cases, respectively. Days with more than 25% ozone loss occurred in 143 days during the last 20 springs. Significant increases of UV-B were observed under ozone hole conditions, especially around 300 nm, the most carcinogenic wavelengths. CONCLUSIONS: Highly unusual ozone loss and UV-B increases have occurred in the Punta Arenas area over the past two decades resulting in the non-photoadapted population being repeatedly exposed to an altered solar UV spectrum with a greater effectiveness for erythema and photocarcinogenesis. This phenomenon has not previously been reported over other populated areas and an additional increase in the skin cancer rate attributable to the AOH may be occurring. Research on the clinical and subclinical impact of these abnormalities is urgently needed. 相似文献
995.
Endoscopy in Patients Receiving Radiation Therapy to the Thorax 总被引:3,自引:0,他引:3
Radiation therapy for thoracic malignancies is often complicated by radiation-induced esophagitis. Symptoms of radiation esophagitis are nonspecific and include dysphagia, odynophagia, and chest pain. Patients receiving radiation therapy are also at risk for infectious esophagitis, which can be indistinguished clinically from radiation-induced esophagitis. We retrospectively reviewed data on patients who had esophagitis symptoms during or after thoracic radiation therapy and were referred for upper endoscopy. We sought to determine how often infectious esophagitis or cancer was present, as compared to radiation-induced esophagitis alone. Twenty-four upper endoscopies were performed on 16 patients over a three-year period to evaluate esophagitis symptoms. Forty-four percent of the patients endoscoped had infectious esophagitis or recurrent cancer diagnosed by endoscopy. No complications occurred from the procedures. Esophagoscopy is a safe procedure that should be considered, to exclude infection or cancer, in patients who develop esophagitis symptoms during or after thoracic radiation. 相似文献
996.
Anderson TD Weber RS Guerry D Elder D Schuchter L Loevner LA Rosenthal DI 《Head & neck》2002,24(12):1068-1071
BACKGROUND: Desmoplastic neurotropic melanoma (DNM) is an uncommon cutaneous melanoma variant with pronounced neurotropism. In contrast to ordinary melanomas, locoregional recurrences are common and distant metastasis are uncommon in patients with DNM. Local control with surgery and radiation therapy may assume a more important role in this variant of melanoma. We present a case of an unresectable skull base recurrence of DNM that was controlled using radiation therapy alone and review the literature. METHODS: Case report with 36-month follow-up. RESULTS: The patient is a 68-year-old with multiple recurrences of a DNM that originated on the forehead. After extensive surgery, including total parotidectomy and temporal bone resection, the patient had an unresectable recurrence of the skull base develop. This was treated with definitive radiation therapy, resulting in a complete response. The patient has had no evidence of recurrence at 3 years. CONCLUSIONS: DNM is a locally aggressive type of melanoma with a high risk of local recurrence that can be radioresponsive. The incidence of distant metastasis is low, so aggressive treatment to control local disease is warranted. This may include surgery plus adjuvant radiation therapy or definitive radiotherapy for unresectable recurrences. 相似文献
997.
Combined gene therapy and ionizing radiation is a novel approach to treat human esophageal adenocarcinoma 总被引:19,自引:0,他引:19
Gupta VK Park JO Jaskowiak NT Mauceri HJ Seetharam S Weichselbaum RR Posner MC 《Annals of surgical oncology》2002,9(5):500-504
Background The ability to infect tumor cells limits the antitumor effects of gene therapy. The addition of radiotherapy to treatment
with Ad.Egr.TNF.11D, a replication-deficient adenovirus containing a radiation-inducible promoter, early growth response-1,
and the tumor necrosis factor-α (TNFα) complementary DNA may enhance the therapeutic ratio.
Methods Seg-1 human esophageal adenocarcinoma cells were treated with Ad.Egr.TNF.11D with or without radiation. TNFα levels were quantified
with enzyme-linked immunosorbent assay. Athymic nude mice bearing Seg-1 tumors were randomized to buffer, ionizing radiation,
Ad.Egr.TNF.11D, and combination therapy. Tumor growth delay was used to compare treatment regimens. TNFα levels were measured
in tumor homogenates and plasma.
Results Seg-1 cells treated with Ad.Egr.TNF-11D and ionizing radiation demonstrated increased TNFα levels at 72 hours compared with
cells exposed to vector alone (124±0 pg/mL vs. 31.11±22 pg/mL;P=.008). In vivo, Ad.Egr.TNF.11D-treated tumors expressed low TNFα levels (151.5 ±107.11 pg/mg protein) compared with tumors
receiving combined treatment (793.92±489.13 pg/mg protein;P=.067). Increased TNFα levels were associated with increased tumor growth delay after combined treatment (P<.05).
Conclusions Radiotherapy enables focal stimulation of TNFα expression in Ad.Egr.TNF.11D-infected cells and thus improves local tumor control. 相似文献
998.
A case of radiation-induced sarcoma of the chest wall is reported. Twenty-seven years 11 months after orthovoltage radiotherapy of the right breast a 69-year-old woman developed a radiation-induced osteosarcoma of the right thoracic wall. Initial diagnosis has been T-cell lymphoma of the skin. The right breast was irradiated with tangential fields and a total dose of 40 Gy, 2 Gy/day, 5 days a week. Orthovoltage treatment was performed in two courses of 20 Gy, 3 months apart. The clinical appearance of the secondary sarcoma was a diffuse infiltrated area in the irradiated breast which seemed to be fixed to the chest wall. Magnetic resonance imaging (MRI) demonstrated a mass in the right anterior thoracic wall which destroyed the fourth to the sixth rib. The tumor infiltrated the thoracic wall, including subcutaneous tissue and pericardium, as well as extending into the subphrenic space. Biopsy of the lesion revealed a poorly differentiated osteosarcoma. The patient's general condition precluded surgical or chemotherapeutic intervention; she died due to a cerebral stroke 6 months later. This case fulfilled all criteria for radiation-induced sarcoma, as there was a prior history of radiotherapy, latency period of several years, development of sarcoma within the irradiated field, and histologic confirmation of sarcoma. 相似文献
999.
Burmeister BH Smithers BM Davis S Spry N Johnson C Krawitz H Baumann KC 《ANZ journal of surgery》2002,72(5):344-348
Background: The role of adjuvant radiation therapy following resection of malignant melanoma involving regional lymph nodes remains controversial. There is no published randomized trial comparing surgery alone to surgery with postoperative radiation therapy that shows a benefit in terms of local control. Some retrospective studies, however, suggest that radiation given postoperatively reduces local recurrence. One of the obstacles to patients routinely being offered radiation therapy is the concern over the added late toxicity that may occur. The present article is a report of the first 130 patients of a prospective phase II multicentre study in Australia and New Zealand. Methods: The study was aimed at patients who had had a resection of melanoma in regional nodes or in a regional node basin. The patients were given adjuvant radiation therapy to a recommended dose of 48 Gy in 20 fractions over 4 weeks using accepted radiation techniques for each of the major node sites. This report describes the late toxicity of the treatment received by these patients. Results: The results of late toxicity experienced in the study were acceptable. Conclusion: The regimen of radiation therapy used could form the basis for the treatment arm of a randomized trial. 相似文献
1000.
Changes in the practice of radiation oncology have been significant over the last decade and continue to develop at an exciting rate. These advances range from our understanding of the increasingly important role of radiotherapy in the adjuvant and definitive settings to huge technological progress in the areas of tumour delineation, treatment planning, delivery and verification. In many cases, benefits have resulted from the ability of modern radiotherapy to deliver high doses with great accuracy and increasing safety in a highly individualized manner. This has impacted favourably on the management of all major malignancies as discussed in this paper. A good understanding of what can be achieved with modern radiotherapy has never been more important in ensuring an effective multidisciplinary approach to cancer management. 相似文献