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71.
Yttrium-90 is used for palliative therapy for the treatment of skeletal metastases, but because it is a pure - emitter, data on the pharmacokinetics and radiation doses to metastases and unaffected organs are lacking. To obtain such data, the present study employed yttrium-86 as a substitute for90Y, with detection by positron emission tomography (PET). The study compared the properties of two different86Y complexes —86y-citrate and86Y -ethylene diamine tetramethylene phosphonate (EDTMP) — in ten patients with prostatic cancer who had developed multiple bone metastases (the ten patients being divided into two groups of five). Early dynamics were measured up to 1 h post injection (p.i.) over the liver region, followed by subsequent whole-body PET scans up to 3 days p.i. Absolute uptake data were determined for normal bone, bone metastases, liver and kidney. Radiation doses were calculated according to the MIRD recommendations. Based on the pharmacokinetic measurements of the distribution of the86Y complexes, it was possible to calculate radiation doses for the bone metastases and the red bone marrow delivered by complexes containing90Y. In 1 cm3 of bone metastasis, doses of 26±11 mGy/MBq and 18±2 mGy/MBq were determined per MBq of injected90Y- citrate and90Y- EDTMP, respectively. The doses to the bone marrow were 2.5±0.4 mGy/MBq for90Y- citrate and 1.8±0.6 mGy/MBq for90Y-EDTMP.86Y and PET provide quantitative information applicable to the clinical use of90Y. This method may also be useful for the design of other90Y radiopharmaceuticals and for planning radiotherapy dosages.  相似文献   
72.
Pollen JJ 《The Prostate》1980,1(2):251-258
This report reviews the roles of conventional radiography, computerized axial tomography, and nuclear bone scanning in the diagnosis, staging, follow-up, and management of prostatic cancer. Computed tomography (CT) offers great promise for the better definition of the extent of the primary tumor of prostatic cancer. It contributes positively to the planning of radiation therapy portals in the treatment of localized disease. By means of bipedal lymphangiography and CT scanning, pelvic and periaortic lymphadenopathy may be detected more often than was previously possible without staging pelvic lymphadenectomy, which can be reserved for the discovery of microscopic disease. Soft-tissue metastases that are located deep within the body cavities can now be measured accurately by CT scanning, as can their response to therapy. Skeletal metastases, the most common variety in prostatic cancer, can be detected with a high degree of sensitivity by nuclear bone imaging. Serial bone scans are remarkably useful in following the response of osseous deposits to treatment, as well as in detecting relapsing disease. The management of malignant obstruction of the ureters has been greatly facilitated by the application of angiographic techniques to percutaneous nephrostomy performed under fluoroscopic control.  相似文献   
73.
Summary The density of 3 (peripheral type benzodiazepine) binding sites, a marker of reactive and tumoural cells, has been measured in different types of human brain tumours; 3 sites were quantified autoradiographically in sections from biopsy or autopsy specimens labelled with the specific radioligand3H-PK 11195. Compared to normal brain parenchyma, up to 12-fold increase in 3 site densities were found in appparently viable areas of high grade astrocytoma and glioblastoma specimens, whereas more limited increases (2 to 3-fold) in this marker were observed in areas of necrosis. Low grade gliomas (astrocytomas) and meningiomas exhibited only moderate increases (2 to 3-fold) in this autoradiographic marker. Metastases of lung or kidney origin were characterized by greatly elevated (up to 20-fold) 3 site densities as compared to normal brain parenchyma. In every case, there was a good spatial correspondence between the histopathological limits of the tumour and the anatomical location of the increase in 3 site densities. These results suggest that 3 site densities in human brain tumours reflect their proliferative activity and point to a possible future usefulness of positron or gamma-ray emitting 3 site ligands for the clinical investigation and detection of human brain proliferative diseases.  相似文献   
74.
目的观察小分割分次立体定向放射治疗(fractionated stereotatic radiation therapy,FSRT)脑转移瘤的近期疗效.方法15例病人单纯全脑外照射(WBRT组),中间平面剂量20~40Gy/10~20次/2~4周.17例病人接受FSRT(FSRT组),每次分次剂量为2.5~3.0Gy.其中11病人行单纯FSRT,中心总剂量为30~60Gy/1 0~20次/2~4周;6例病人先行WBRT,然后行FSRT,中心总剂量为46~60Gy/5~6周.结果KSP评分增加10分以上者,WBRT组为5 3.3%,FSRT组为82.4%.(P<0.05).WBRT组有效率(CR PR)为50.0%;FSRT组有效率(CR PR)为80.0%.中位生存率:WBRT组为3.5月,FSRT组为10.0月.结论FSRT能有效地控制脑转移瘤,减轻神经系统症状,提高生存质量,延长病人生存期,而没有增加副作用,值得临床推广应用.  相似文献   
75.
Objective To analyze the effect of pain control with radiotherapy in bone metastases from malig-nancies. Methods A total of 72 lesions in forty-two cases with bone mestastases were received 6my X ray. The con-ventional radiotherapy was performed in 28 lesions in the way of 200cGy/fraction,5 fracties/week,total dose of 3000 ~5000cGy. The hypofractionation radiotherapy was.performed in 44 lesions in the way of 400cGy/fracfion,3 frac-tions/week,total dose of 2400~3600cGy. Results Overal pain relief rate was 90.28%, there were no significant differences between the two groups(P 0.05). The pain relief of hypofractionation radiotherapy was faster than anoth-er. Conclusion Radiotherapy is a very effective way to relieve pain in bone metastases from malignacies.  相似文献   
76.
目的 探索早期检测肝组织多药性耐药基因对结肠癌肝转移的预测价值。方法 取裸鼠 4 0只 ,用人结肠癌SW4 80细胞系制作裸鼠原位结肠癌肝转移模型。模型建立的第 10天肝活检取左右肝叶各2mm3 组织 ,用实时荧光定量PCR方法检测多药耐药基因 (multidrugresistancegene,mdr- 1mRNA)的表达 ;模型建立的第 5周观察裸鼠肝脏是否形成肉眼转移灶。结果 经实时荧光定量RT -PCR检测肝活检组织mdr- 1基因 ,在存活的 36只裸鼠中 2 2例高表达 ,平均CT值 (Cyclethreshold ,即反应管内的荧光信号到达设定的域值时所经历的循环数 )为 2 5 90 1,平均拷贝数为 4 2 7× 10 7/ugRNA ,并高表达的 2 2只裸鼠均有肉眼肝转移灶形成 (10 0 % ) ;mdr - 1基因低表达 (平均CT值 33 36 8,平均拷贝数 2 11× 10 5)及无表达的 14只裸鼠中 ,仅 1例形成肉眼肝转移灶 (7 1% ) ,其余 13例均无肉眼肝转移灶形成 (P <0 0 1)。结论 结肠癌肝活检肿瘤细胞mdr- 1mRNA基因高表达与异时的肝转移灶形成有明显的相关性 ,提示检测结肠癌肝组织多药性耐药基因的高表达可以预测异时的肝转移灶形成。  相似文献   
77.
目的:研究高强度聚焦超声(HIFU)治疗大肠癌肝转移病灶的安全性和有效性.方法:18例大肠癌术后肝转移患者31个病灶行HIFU治疗,观察患者生命体征、主要脏器功能、影像学检查(CT或MRI等)、并发症和肿瘤转归的情况.结果:所有患者生命体征平稳,肝、肾功能正常,平均随访16.1个月(6~38个月),失访2例,生存13例,12、18个月生存率分别为83.3%和66.7%,中位生存期16个月;随访25个病灶中,17个肿瘤块缩小超过50%,有5例出现新的转移灶,8例出现皮肤浅Ⅱ度烧伤.结论:HIFU治疗是一种安全、有效和非侵入性治疗大肠癌肝转移病灶的手段.  相似文献   
78.
 目的 评价食管癌术后锁骨上和纵隔淋巴结转移局部放射治疗的意义。方法 回顾性分析1998年 7月~ 2 0 0 0年 2月间收治的 5 7例食管癌术后锁骨上和纵隔淋巴结转移患者 ,局部放射治疗 ,常规分割放疗剂量 5 0~ 70Gy。结果  82 .4 %左右的肿瘤得到局部控制 ,1、2、3年生存率分别为 5 6 .1%、2 9 .8%、10 .5 % ,72 .5 %的病人死于野外转移。结论 转移淋巴结≤ 3cm者放疗后的局部控制率和生存期优于淋巴结 >3cm者。食管癌术后锁骨上和纵隔淋巴结转移经放射治疗后局部可得到有效控制 ,多数病人死于远处转移  相似文献   
79.
Twenty-five patients with osteolytic metastases had computed tomography (CT) scans before and 3 months after palliative radiotherapy. The median % density change following single 8 Gy, 20 Gy/5#, 30 Gy/10# were: 128 (range 98–255), 141 (79–342), and 145 (65–235), respectively. It is feasible to evaluate remineralization of osteolytic lesions with palliative radiotherapy.  相似文献   
80.
The purpose of this study was to prospectively examine the effectiveness and tolerability of a simple radiotherapy technique for the palliation of symptomatic liver metastases. Twenty‐eight patients with symptomatic liver metastases were enrolled from seven centres, and received targeted (partial or whole) liver irradiation consisting of 10 Gy in two fractions over 2 days. Symptoms at baseline were hepatic pain (27 patients), abdominal distension (19), night sweats (12), nausea (18) and vomiting (eight). Twenty‐two patients (76%) had failed previous treatment with chemotherapy, hormonal therapy and/or high‐dose steroids. Symptoms and potential toxicities were prospectively assessed at the time of treatment, then 2, 6 and 10 weeks later. Individual symptom response rates were 53?66% at 2 weeks. Partial or complete global symptomatic responses were noted in 15 patients (54%) overall. The treatment was well tolerated with two patients (7%) experiencing grade 3 toxicity (one vomiting and one diarrhoea); however, four patients reported temporary worsening of pain shortly after treatment. This simple and well‐tolerated treatment achieves useful palliation.  相似文献   
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