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991.
The purpose of this study was to assess the feasibility of imaging of bladder cancer with fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scanning. We studied 12 patients with histologically proven bladder cancer who had undergone surgical procedures and/or radiotherapy. Retrograde irrigation of the urinary bladder with 1000–3710 ml saline was performed during nine of the studies. Dynamic and static PET images were obtained, and standardized uptake value images were reconstructed. FDG-PET scanning was true-positive in eight patients (66.7%), but false-negative in four (33.3%). Of 20 organs with tumor mass lesions confirmed pathologically or clinically, 16 (80%) were detected by FDG-PET scanning. FDG-PET scanning detected all of 17 distant metastatic lesions and two of three proven regional lymph node metastases. FDG-PET was also capable of differentiating viable recurrent bladder cancer from radiation-induced alterations in two patients. In conclusion, these preliminary data indicate the feasibility of FDG-PET imaging in patients with bladder cancer, although a major remaining pitfall is intense FDG accumulation in the urine. Present address: Department of Radiology, National Defense Medical College, 3-2 Namiki, Tokorozawa 359, Japan  相似文献   
992.
Abstract: Coagulation leading to fibrosis of mammo-graphically detected breast cancers by interstitial laser therapy was tested as an alternative to surgical removal. Availability of computerized stereotaxic digital imaging allows the precise placement of laser and thermal needles into the target tumor and its controlled ablation by heat. The methodology of interstitial laser therapy (ILT), evolution of the subsequently removed tumors, and their histologic appearance are outlined.
Eight patients with mammographically well-defined tumors were selected. Definitive diagnosis and receptor evaluation were made on core biopsies. Under local anesthesia, stereotaxically guided diode laser energy at 5–10 w was delivered via a 400 xm fiber in a 19-gauge needle placed into the center of the tumor until the peripheral temperature exceeded 60°C. Patients experienced transient pain and pyrexia. Subsequent to ILT, seven invasive carcinomas were excised while one case of multiple papillomas was kept under surveillance. Histologic study revealed central necrosis but some peripheral residual tumor in the first five cases. In the last two, central necrosis surrounded by concentrically arranged, recognizable but severely injured, focally "windswept" and "ghostlike" tumor and granulation tissue were noted. The multiple papillomas showed radiologic shrinkage at 5 months and extensive fibrosis on needle biopsy.
ILT is an attractive new method of treating small, well-defined breast tumors and offers a potentially significant alternative to surgical removal; further exploration is warranted.  相似文献   
993.
The ovarian and pituitary functions of 64 operable breast cancer patients undergoing adjuvant therapy with cytotoxic chemotherapy and/or tamoxifen were investigated. The post menopausal patients, divided into 3 treatment groups, one with tamoxifen alone, one with tamoxifen and chemotherapy and the other with chemotherapy alone had serum estradiol 17-β (E2) and progesterone levels lower than the evaluable limits. Although there was no significant difference in the level of estrone sulfate (E1-S) between these three groups, the level of lutainizing hormone (LH) and follicle stimulating hormone (FSH) in the patients treated with tamoxifen alone and tamoxifen and chemotherapy were significantly lower than those treated with chemotherapy alone. The decrease in gonadotropin levels induced by tamoxifen treatment was reversible as it appeared after the initiation of tamoxifen and recovered after its cessation. In the premenopausal patients, a group treated with tamoxifen and chemotherapy had significantly higher E1-S, E2 and progesterone levels and significantly lower gonadotropin levels than a group treated with chemotherapy alone or one treated with a cyclophosphamide regimen. These increases in the levels of estrogen and progesterone were also reversible, and induced by tamoxifen. Thus, adjuvant endocrinochemotherapy causes profound alteration in the hypothalamo-pituitary-ovarian axis and therefore, monitoring a variety of hormonal levels is thought to be necessary for assessing the consequences of adjuvant therapy in breast cancer patients, especially in premenopausal patients using tamoxifen.  相似文献   
994.
The present paper critically appraises two recent overviews of the literature on rectal cancer and quality of life (QL). These reviews focus on the Anglo-American literature, largely neglect research from other countries, and provide little stimulus regarding future research directions. As an alternative perspective we propose the concept of problem-solving oriented QL research. The major theme is that the QL concept must be integrated into the clinical arena. To begin with, QL researchers must make themselves understandable. We outline several ways in which this can be achieved: (a) placing QL in a broader concept together with outcomes that are more familiar to clinicians; (b) depicting individual patients in the form of QL profiles; (c) clarifying the psychosocial/clinical correlates of particular QL scores of interest; and (d) conducting studies with a definitive practical goal in mind and integrating practitioners and patients into the study group. We illustrate the feasibility of such a research program by performance data from our Marburg-Biedenkopf field trial. Pursuing an ambitious research strategy that integrates experimental and applied research, the QL movement will have the chance to show that it is not merely l'art pour l'art, but indeed is beneficial to society. Received: 28 September 1998 / Accepted: 14 October 1998  相似文献   
995.
作者对结节性甲状腺肿及其非典型结节与甲状腺癌细胞核直径、面积及 DNA 含量检测,发现核直径与面积的(?)和 S 为甲状腺癌组>非典型结节组>对照组(P<0.01);随着细胞增生异型程度的加重,核直径、面积及离散程度随之增加、DNA 含量也显著增加,显示Ⅲ级 DNA 含量细胞出现频率越高恶性的可能性就越大;同时发现各组细胞核不同 DNA 含量的核直径、面积均明显增加,与对照组相比差异生非常显著(P<0.01)。  相似文献   
996.
血清肿瘤标志物联合检测在肺癌诊断中的应用   总被引:4,自引:0,他引:4  
张伟  陈瑛  张鹏 《天津医科大学学报》2003,9(2):209-210,222
目的:探讨血清19片段角蛋白((2YFRA21-1)、神经元特异性烯醇化酶(NSE)、癌胚抗原((CEA)、β2微球蛋白(β2-MG)联合检测提高肺癌的阳性率,为临床提供早期诊断、治疗的依据。方法:采用电化学发光和免疫比浊法检测155例肺癌、72例肺良性疾病和50例正常人血清CYFRA21-1、NSE、CEA和β2-MG的水平。结果:肺癌4项标志物联合检测阳性率明显高于肺良性疾病组和健康人正常对照组,其中CYFRA21-1阳性率以鳞癌最高(77.7%),与其它型肺癌存在显著差异。NSE阳性率以小细胞性肺癌最高(78.4%),与其它型肺癌存在显著差异。结论:CYFRA21-1、NSE、CEA、β2-MG是诊断肺癌有价值的肿瘤标志物组合,有助于提高肺癌诊断的阳性率、特异性和准确性。  相似文献   
997.
The most common cause of death in patients with colorectal cancer is metastatic liver disease. In order to identify patients at a high risk of developing hepatic secondaries from colorectal cancers, DNA content was measured in metastasizing colorectal primaries (Group I, n= 32) as well as in their subsequently resected liver secondaries and in sections of non-metastasizing colorectal cancers (Group II, n= 25). A modified interpretation system involving both a DNA index and percentage of cycling cells (those in S and G2 + M phases) was developed. DNA content was measured in paraffin-embedded sections by flow cytometry using internal controls (human peripheral blood mononuclear cells) and non-malignant tissue controls (19 patients with diverticular disease). In Group I there were significantly more tumours with both abnormal ploidy (aneuploid or abnormal tetraploid peak) and > 15% cycling cells compared with Group II (Chi-squared; P= 0.034). The combination of abnormal ploidy and > 15% cycling cells was superior to Dukes’ classification for identifying metastasizing tumours (Logistic Regression; P= 0.047). However, it was not possible to discriminate between the two groups using either DNA ploidy or the percentage of cycling cells alone. The metastasizing colorectal cancers exhibited similar DNA ploidy characteristics and had a similar percentage of cycling cells compared with their liver metastases. These results suggest that tumour DNA ploidy plus the percentage of cycling cells may predict the development of liver metastases and thus survival in patients with colorectal cancer.  相似文献   
998.
John T. Leith 《The Prostate》1994,24(3):119-124
Because there is extremely limited information on the intrinsic radiosensitivity of human prostatic cancer cells, we have investigated the in vitro radiation response of exponentially growing LNCaP cells. Due to the very poor colony-forming potential of the LNCaP cells, radiation survival was investigated using the dose-dependent (0-6 Gy) changes seen after X-irradiation in the shapes of regrowth curves. Survival was described using both the single-hit, multitarget (SHMT) equation and the linear-quadratic (LQ) equation. The values and 95% confidence limits of the extrapolation number (n), quasi-threshold dose (Dq), and mean lethal dose (Do) in SHMT terminology were respectively: 0.9 (0.7-1.0), 0.0 Gy, and 1.39 (0.11) Gy. The LQ alpha and beta parameters were respectively 6.80 (1.13) and -0.53 (2.89). The X-ray dose response of the LNCaP line is, therefore, purely exponential. The mean survival at the clinically relevant dose of 2 Gy (S2) was 51.2% for the LNCaP line. Comparison of the S2 value for the LNCaP line with previous investigations with other human prostatic cancer cell lines (DU145 and PC-3) indicates a mean S2 value of 47.6%, which suggests that human prostate cancer cells might lie toward the resistant side of the spectrum for various classes of human neoplasms. © 1994 Wiey-Liss, Inc.  相似文献   
999.
目的研究α1AT(α1-antitrypsin)在肺癌组织中的表达及其病理学意义。方法检测141例肺癌患者及162例正常对照血清α1AT活性。通过免疫组化方法研究α1AT在肺癌组织中的表达,分析其与肺癌组织分型、分化程度及临床分期的关系。结果α1AT活性在肺癌患者中明显降低,α1AT活性低者肺癌发生的危险性升高。肺癌组织α1AT表达显著升高,α1AT表达与肺癌的临床分期相关,但与肺癌组织类型无关。结论α1AT在肺癌的发展与演进中可能具有重要的意义。  相似文献   
1000.
趋化因子在免疫调节、血管新生以及介导肿瘤的器官特异性转移中发挥重要作用。其中CXC趋化因子超家族由于N-端谷氨酸-亮氨酸-精氨酸基序(Glu-Leu-Arg,ELRmotif)的有无使其在血管新生过程中具有了促进或者抑制血管新生的不同作用:含有ELR(ELR )的CXC趋化因子经血管内皮组织上CXCR2介导血管新生促进作用;而不含有ELR(ELR-)的CXC趋化因子通过血管内皮组织上CXCR3介导血管新生抑制作用。  相似文献   
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