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1.
目的:观察支架置入法对食道癌患者的治疗效果及预后情况。方法:选取我院收治的食道癌患者共104例,根据治疗手段分为两组,其中对照组52例采用70 Gγ7/周治疗方案;实验组52例给予支架置入法治疗。对两组患者的梗阻改善情况、生存质量评分、并发症及生存情况进行统计分析。结果:1治疗后,两组患者的梗阻情况以及生存质量均得到有效改善,实验组患者的梗阻总缓解率为92.31%,生存质量评分为42.61±5.23分,均显著高于对照组,差异具有显著性(P0.05);2实验组患者的不良反应发生率(36.54%)与对照组(38.48%)比较无统计学差异(P0.05);3两组患者的3个月及6个月时的生存率相接近,但是实验组患者12个月生存率(71.7%)显著低于对照组(82.7%),差异具有统计学意义(P0.05)。结论:支架置入法能够显著改善食道癌患者的梗阻症状,提高患者生存质量,是较为安全可靠的缓解食道狭窄方法。  相似文献   
2.
PurposeThis study aims at characterizing the dosimetric behavior of an INTRABEAM® miniature accelerator equipped with flat and surface applicators, converting the spherical dose distribution into a flat one.MethodsDosimetric characterization was carried out in two steps. Firstly characterization was made in standard conditions for dermatologic applications, which is with the applicator directly on contact with the skin. Secondly, characterization was made in more clinical conditions, such as obliquities and heterogeneities.ResultsBehaviors of flat and surface applicators are different. Dose distribution for surface applicators is uniform at surface, whereas for flat applicator the maximum homogeneity is shown at a particular depth in water. Some results are different from previously published studies due to differences in the X-ray source design. The study showed that in the absence of a perfect contact between the applicator and the skin of the patient, there is a dose distribution spread on the edge of the irradiation field where the contact is not made. Dose loss due to lack of backscatter radiations is significant. By contrast, influence of a denser material behind the measurement point has no significant influence on the dose at this point. Thickness of tissue treated with flat and surface applicators is only a few millimeters, depending on the applicator's size, making these applicators ideal for superficial lesions, compared to high energy electrons and iridium brachytherapy.ConclusionsThe INTRABEAM® miniature accelerator equipped with surface applicators is a reliable way of treating superficial cutaneous malignancies.  相似文献   
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4.

Objective

To compare and analyze three therapies on patients with primary central nervous system lymphoma (PCNSL), aiming to provide evidences for future treatment and prognosis.

Methods

Clinical data of 26 cases of PCNSL with normal immune system confirmed by postoperative pathology were retrospectively analyzed. Among them there were six cases with operation only, nine cases with operation and radiotherapy, and 11 cases with operation, radiotherapy and chemotherapy, and their survival rate was compared as well.

Results

The survival time of patients with operation only, operation combined with radiotherapy and operation combined with radiotherapy and chemotherapy was 6–11?months, 15–24?months and 24–51?months, respectively. And their median survival time was only nine months, 21?months and 38?months, respectively.

Conclusions

Operation combined with radiotherapy and chemotherapy can dramatically extend PCNSL patients’ survival time, therefore, it can be regarded as the first-line therapy.  相似文献   
5.
PurposeTo define a method and investigate how the adjustment of scan parameters affected the image quality and Hounsfield units (HUs) on a CT scanner used for radiotherapy treatment planning. A lack of similar investigations in the literature may be a contributing factor in the apparent reluctance to optimise radiotherapy CT protocols.MethodA Catphan phantom was used to assess how image quality on a Toshiba Aquilion LB scanner changed with scan parameters. Acquisition and reconstruction field-of-view (FOV), collimation, image slice thickness, effective mAs per rotation and reconstruction algorithm were varied. Changes were assessed for HUs of different materials, high contrast spatial resolution (HCSR), contrast-noise ratio (CNR), HU uniformity, scan direction low contrast and CT dose-index.ResultsCNR and HCSR varied most with reconstruction algorithm, reconstruction FOV and effective mAs. Collimation, but not image slice width, had a significant effect on CT dose-index with narrower collimation giving higher doses. Dose increased with effective mAs. Highest HU differences were seen when changing reconstruction algorithm: 56 HU for densities close to water and 117 HU for bone-like materials. Acquisition FOV affected the HUs but reconstruction FOV and effective mAs did not.ConclusionsAll the scan parameters investigated affected the image quality metrics. Reconstruction algorithm, reconstruction FOV, collimation and effective mAs were most important. Reconstruction algorithm and acquisition FOV had significant effect on HU. The methodology is applicable to radiotherapy CT scanners when investigating image quality optimisation, prior to assessing the impact of scan protocol changes on clinical CT images and treatment plans.  相似文献   
6.
The hprt T-lymphocyte cloning assay, which detects mutations occurring in vivo in humans, has been used to examine mutants induced in patients receiving radioimmunoglobulin therapy (RIT) for cancer. Samples from 13 patients before treatment (controls) and 15 samples from 12 patients after treatment were studied for both mutant frequencies and molecular changes in the hprt mutant T-cell clones. Patients were studied up to 48 months after treatment. Post-RIT patients showed increased mutant frequencies as compared to pre-treatment values. T-cell receptor (TCR) gene analysis of mutant T-cell clones demonstrated that 84% arose independently, both pre- and post-treatment, which is the same proportion as seen in normal individuals. However, several individuals did show large sets of mutants with the same TCR gene rearrangement patterns. Molecular analysis of mutants demonstrated a greater proportion of mutations with hprt gene changes on Southern blots after RIT treatment than before (40% versus 20%). RIT increases the proportion of mutations with total rather than partial gene deletions or other gross structural changes compared to normal individuals or pre-treatment patients. These studies are defining the spectrum for radiation-induced hprt gene mutations in vivo in human T-lymphocytes.  相似文献   
7.
We predict, for the first time, that by using United States Food and Drug Administration approved concentrations of cisplatin, major radiosensitization may be achieved via photoelectric mechanism during concomitant chemoradiotherapy (CCRT). Our analytical calculations estimate that radiotherapy (RT) dose to cancer cells may be enhanced via this mechanism by over 100% during CCRT. The results proffer new potential for significantly enhancing CCRT via an emerging clinical scenario, where the cisplatin is released in-situ from RT biomaterials loaded with cisplatin nanoparticles.  相似文献   
8.
Background/AimTo analyse clinical response, overall (OS) and disease free survival (DFS) and toxicity in patients with unresectable oesophageal cancer treated by concomitant chemo-radiotherapy (CRT).Materials and methodsForty patients with stage IIa–IVa biopsy proven oesophageal carcinoma were treated with CRT. All patients were studied with endoscopy and CT and judged unresectable after multidisciplinary discussion. CRT consisted of 3 cycles of cisplatin 100 mg/m2 or carboplatin 300 mg/m2 on day 1 and 5-fluorouracil 1000 mg/m2 as a continuous infusion of 96 h associated with concurrent 3D-conformal RT. By using 15 MeV X-rays, a total dose of 60–66 Gy was delivered with daily fractions of 1.8–2.0 Gy.ResultsComplete response (CR), partial response (PR) and no response (NR) were observed in 50%, 20% and 20% of cases, respectively. Of the 20 patients with CR, 15 developed loco-regional recurrent disease. OS and DFS rates at 3 and 5 years were 38%, 8%, 49% and 10%, respectively. Total radiation dose ≥60 Gy improved loco-regional control and complete response (CR vs. PR + NR; p = 0.004) influenced both DFS and loco-regional control. Grade 3 gastrointestinal and haematological acute toxicity occurred in 3/40 patients (7.5%). One patient developed grade 4 renal failure. Late toxicity was reported in 2/40 patients (5.0%), consisting of grade 3 radiation pneumonitis.ConclusionsConcomitant CRT for unresectable oesophageal cancer can result in an acceptable loco-regional control with limited toxicity. Response after treatment and total radiation dose influenced the outcome.  相似文献   
9.
Alveolar echinococcosis is caused by the metacestode stage of the fox tapeworm Echinococcus multilocularis. Current chemotherapeutical options for the treatment of echinococcosis are not satisfactory, and novel drugs and/or other potential means of therapy are needed. E. multilocularis metacestodes are characterized by almost potentially unlimited growth, and also display other features of cancerous tumours. In this study, we exposed metacestodes that were generated in vitro to 50–100 Gy ionizing irradiation, and subsequently investigated the short-term (10–12 days post-treatment) and long-term (14 weeks post-treatment) effects. We found, that in the short-term, no release of alkaline phosphatase (EmAP) activity as a measure for potentially induced damage and loss of viability could be detected, and that the protein expression pattern and protease activities in vesicle fluids and medium supernatants did not alter dramatically following irradiation. However, irradiation was associated with distinct morphological and ultrastructural alterations in the tissue of metacestodes, affecting most notably cell–cell contacts, mitochondrial shape, glycogen-storage cells and lipid droplet formation. These could be detected already at 10 days following treatment and remained as such also in the long-term. In addition, as determined after 14 weeks of culture, irradiation affected the proliferation and the growth of E. multilocularis metacestodes. Thus, we demonstrate that radiotherapy does not have a clear-cut parasitocidal effect, but can lead to metabolic impairment of E. multilocularis metacestodes, as reflected by the distinct morphological and structural alterations induced by irradiation treatment.  相似文献   
10.
BackgroundRadiotherapy is among the most efficient treatment methods of cancer. However, a radiotherapy base needs a substantial financial investment, especially before the beginning of its operation, and in some cases, in developing countries such a huge investment may cause some financial disturbances for a hospital concerned.AimTo assess the influence of investments modernizing the radiotherapy base in the period between 2000 and 2007 on the financial condition of the oncology hospital in the region with population of about 3 million.Material and methodsFinancial reports and medical statistics for the period between 2000 and 2007 from the studied oncology hospital and a recognized staffing model, as well as data on epidemiological situation of the region have been used to calculate the economic effects of financial investment in the radiotherapy base.ResultsThe growth of RT therapeutic potential has been driven by two cost-effective investment programmes. The total amount invested in both programmes was PLN 127,191,000.The number of radiotherapy patients treated in the hospital increased from 2301 in 2000 to 4799 in 2007 with a the same number of five therapeutic machines, although all five of them were replaced over that period. Investments modernizing the radiotherapy base lead to a significant increase in depreciation and operating costs, which adversely affects financial results of the hospital.ConclusionLong term trends showed that investments had positive influence on hospital performance shown both in increased income and larger number of patients treated.  相似文献   
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