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31.
大肠癌组织中端粒酶活性的研究   总被引:23,自引:0,他引:23  
Zhao D  Zhang W  Jin S 《中华肿瘤杂志》1998,20(3):199-201
目的研究大肠癌组织及相应癌旁组织中的端粒酶活性,探讨其作为肠癌肿瘤标记物的可能性。方法采用TRAP方法研究了40例大肠组织(包括37例大肠癌,3例良性大肠疾病)和20例相应癌旁上皮组织中的端粒酶活性表达。结果20例癌旁上皮和3例良性疾病组织中,端粒酶活性表达均为阴性;而37例大肠癌组织中,35例显示端粒酶活性表达为阳性,阳性率为94.6%。结论端粒酶是特异性较强的恶性肿瘤基因标志,有可能成为大肠癌早期诊断和治疗的理想标志物  相似文献   
32.
BACKGROUND: Positron emission tomographic (PET) scanning utilizing [18F]fluorodeoxyglucose (FDG) is a new method of tumor imaging based on the increased glucose metabolic activity of malignant tumors. In Hodgkin's disease (HD), PET has proven value for the evaluation of residual masses following treatment and for the early diagnosis of relapse. In the initial staging of HD, PET frequently shows a higher stage than conventional methods (upstaging by PET). In the present study, we evaluated the frequency of stage changes by PET in a multicenter setting and determined its prognostic relevance. PATIENTS AND METHODS: A total of 73 patients with newly diagnosed HD were staged with both conventional methods and whole-body PET scanning. All histological types and stages were represented. The median time of follow-up after the initial diagnosis was 25 months (range 1 month to 5 years). The response to treatment was determined by standard clinical and diagnostic criteria. For the purpose of this analysis, data from a PET center associated with a university medical center and a PET center associated with a group oncology practice were combined. RESULTS: A total of 21 patients (28.8%) were upstaged by PET compared with conventional methods. In two cases (2.7%), a lower stage was suggested by PET scanning. With one possible exception, the upstaging had no obvious clinical or biological correlate. Among 12 patients in stage I (A + B) by conventional methods, seven were upstaged by PET (58.3%), four to stage II, one to stage III and two to stage IV. Among 42 patients in stage II, eight were upstaged by PET (19.0%), six to stage III and two to stage IV. Among 12 patients in stage III, six (50%) were upstaged to stage IV by PET. If only early-stage patients and major changes are considered (stages IA-IIB to III or IV), among 49, 10 were upstaged to III or IV, whereas in 39 staging was unchanged following PET. In the former group, three relapsed or were refractory compared with none in the latter group (P<0.006). In advanced stage patients (IIIA or IIIB) a trend toward treatment failure was apparent in patients who were upstaged by PET. CONCLUSIONS: PET scanning is an interesting new modality for the accurate staging of patients with HD and frequently shows a higher stage than conventional methods. PET should be performed at initial diagnosis and should be included in prospective studies of patients with HD. Upstaging by PET may represent a risk factor for a more advanced stage or a biologically more aggressive tumor. Patients with early-stage disease as identified by conventional methods have a significant risk of treatment failure if a more advanced stage is indicated by PET. At present, major stage changes suggested by PET imaging should be confirmed by an independent diagnostic method.  相似文献   
33.
PET在肺癌诊断和分期中的应用   总被引:4,自引:0,他引:4  
林祥通  赵军 《中国癌症杂志》2003,13(5):402-404,415
本文介绍正电子发射断层显像(PET)在肺癌诊断和分期中的应用概况,肯定了其临床应用价值。并简要叙述我国PET目前现状及今后展望。PET系大型医疗设备,我国未纳入医疗保险,其发展要根据社会经济发展和病人承受能力,合理布局,有限量地增加。作者指出,加强核医学科人员培训与临床各科医师(包括放射科,肿瘤科,胸外科,放射治疗等)的合作是提高PET临床应用和研究水平的关键因素。  相似文献   
34.
Objective.The aim of this study was to define the clinical–therapeutical approach to endometrial cancer now being followed in some of the most important centers of reference for gynecological cancer in North America by means of a questionnaire.Study design.The questionnaire focused on four principal areas: (1) surgical staging and therapy; (2) adjuvant treatment; (3) treatment modifications; and (4) management of advanced stages (FIGO III–IV).Results.There were 48 evaluable responses (77%) received by the end of December 1994 which were considered for this analysis. Lymphadenectomy is utilized routinely in 26/48 centers (54.2%) and in selective clinical–pathological conditions in another 21/48 centers (43.5%). In the majority of centers (31/48; 64.6%) radical surgery is utilized for selected indications such as cervical involvement. Only 3/48 (6.2%) centers consider the vaginal approach totally inappropriate. The great majority (40/48; 83.3%) of the centers considered postsurgical adjuvant therapy to be necessary in FIGO Stage Ic. Brachytherapy is routinely performed in 3 centers (6.2%) in postsurgical management of Stage I endometrial cancer, while the majority of the centers (31/48; 64.6%) perform brachytherapy of the vaginal vault in certain clinical–pathological conditions. A wide variety of treatments are used for advanced stages (FIGO III–IV).Conclusions.It emerges that some controversial aspects exist on endometrial cancer treatment, and these conflicting data need a large-scale multicenter randomized clinical trial.  相似文献   
35.
目的评价MRI在喉癌术前T分期中的价值。方法对59例喉癌的MRI资料进行回顾性分期,并与纤维喉镜及手术病理对照。结果MRI对各期喉癌分期的准确性分别是:T1:95%(20/21),T2:88%(15/17),T3:85%(11/13)T4:100%(8/8)。纤维喉镜分期的准确性是:T1:91%(19/21),T2:88%(15/17),T3:47%(8/13),T4:13%(1/8)。结论MRI能准确判断会厌前间隙(PES)、喉旁间隙(PGS)浸润及软骨破坏,因而可显著提高喉癌术前分期的准确性,对临床治疗方案选择具有重要意义。  相似文献   
36.
目的 评价腔内超声(EU)对食管癌术前分期的准确性.方法30例食管癌患者术前进行EU(5MH_z直径 10mm)检查,其中8例(26.7%)因狭窄严重未能对肿瘤进行全面探测.全部患者均接受手术治疗,将术前临床分期.EU分期的结果与术后病理分期进行对比分析.结果 术前临床分期正确率仅为40%.EU对肿瘤外侵程度(T)、区域淋巴结受累情况(N)及术前分期的正确率在全组分别为76.7%、66.7%和70.0%,若去除严重狭窄病例后上升为77.7%、77.7%和77.3%.结论 EU能相当准确地对食管癌进行术前分期,提示肿瘤有无外侵或淋巴结转移,为治疗提供指导.病灶周围炎症反应、肿瘤微转移灶及严重狭窄是影响分期正确性的重要因素.  相似文献   
37.
Purpose: The impact of severity of endometriosis on the outcome of in vitro fertilization (IVF) was analyzed in an uncontrolled, retrospective study in an academic IVF program. Methods: Sixty-one patients with a primary diagnosis of endometriosis undergoing 85 cycles of IVF were included in the study. Patients were divided according to the severity of disease based on the revised American Fertility Society (AFS) classification into groups A (stages I/II, or minimal/mild) and B (stages III/IV, or moderate/severe). Group A included 32 patients undergoing 45 IVF-embryo transfer (ET) cycles; group B included 29 patients undergoing 40 IVF cycles. Exclusion criteria were age older than 40 years, basal day 3 follicle stimulating hormone (FSH) greater than 20 IU/L, male-factor infertility, assisted hatching, and gamete intrafallopian transfer cases. Stimulation for IVF cycles was standard using pituitary down-regulation with gonadotropin-releasing hormone agonist in a midluteal protocol. Controlled ovarian hyperstimulation (COH) was achieved using a combination of FSH and human menopausal gonadotropin. Outcomes assessed included response to COH and number, maturity, and quality of oocytes retrieved. Fertilization, implantation, and pregnancy rates after IVF-ET were also analyzed. Results: The response to COH and the number, maturity, and quality of the oocytes was comparable between patients with varying severity of endometriosis. Fertilization rates for oocytes of patients in group B (stages III/IV) were significantly impaired compared to those in group A (stages I/II) (P = 0,004). The rates for implantation, clinical pregnancy, and miscarriage were comparable between the two groups. Conclusions: The reduced fertilization potential of the oocytes obtained from patients with severe endometriosis in the absence of male-factor infertility suggests an adverse biological impact of the advanced disease on the oocytes. The outcome of IVF-ET, however, is unaffected by increasing severity of endometriosis. This suggests that IVF may compensate for or overcome this reduction in the biological potential of the oocytes associated with severe disease, thus accounting for a comparable outcome irrespective of the severity of endometriosis.  相似文献   
38.
腔内超声对直肠癌术前分期诊断的应用价值   总被引:6,自引:1,他引:6  
目的:评价腔内超声(ELUS)对直肠癌术前分期诊断的准确性及局限性.方法:对58例直肠癌术前行ELUS检查,参考TNM分期标准进行术前分期诊断,并与手术及术后病理结果对照.结果:ELUS对58例直肠癌浸润深度诊断符合率达79.3%,T1、T2、T3、T4各期诊断灵敏度分别为100%、58.8%、87.5%、83.3%.对T2期诊断灵敏度最低,误诊7例中6例过深判断为T3期,且均为溃疡型腺癌.ELUS对54例直肠癌淋巴结转移诊断灵敏度、特异度、准确度分别为76.9%、75.0%、75.9%.淋巴结转移ELUS漏诊6例,淋巴结转移ELUS诊断假阳性7例.结论:ELUS对直肠癌浸润深度及肠周淋巴结转移诊断准确度较高,可成为直肠癌术前分期诊断良好的方法.对T2期的过深判断为影响诊断符合率的重要因素,肿瘤导致肠腔明显狭窄或肿瘤位于直肠上段也影响ELUS的准确性.  相似文献   
39.
目的研究肝癌组织、癌旁组织中乙型肝炎表面抗原(HBsAg)、丙型肝炎病毒(HCV)抗原表达与肝组织纤维化分期的相关性.方法采用免疫组织化学方法对肝癌组织及癌旁组织中的HBsAg、HCV抗原表达进行了标记和分析,同时对肝癌组织及癌旁组织进行肝组织纤维化分期.结果肝组织纤维化程度与HBV、HCV感染有明显相关性(rs=0.32,P=0.001);HBsAg和HCV抗原在癌组织及癌旁组织中表达有差异,HBsAg主要在癌旁组织表达(79%),高于癌组织(23%);而HCV抗原在癌组织(15%)与癌旁组织表达(23%)水平相当.结论有病毒感染背景的肝癌组织,其纤维化程度高于无病毒感染的肝癌组织;病毒的感染是肝癌发生的原因,长期的病毒血症会加速肝纤维化的进展.  相似文献   
40.
The ultrasonographic appearances of osteosarcomas and the roles of ultrasonography in the diagnosis and surgical staging of osteosarcomas were investigated. A comparative study was performed on 45 cases of osteosarcomas by ultrasonography and radiography. Bony changes, periosteal reaction and soft tissue mass were evaluated for each lesion. The results showed that ultrasonography revealed a solid mass around bone in 42 patients, bone destruction in 24 patients and periosteal reaction in 16 patients. Plain radiographs showed bony changes in 44 patients and no bony change in remaining one patient, shadowing of soft tissue swelling in 30 patients, and pulmonary metastases in 3 patients. Surgical biopsy and pathological examination confirmed osteosarcoma in all 45 patients. Soft tissue mass was confirmed in 42 patients surgically. The diagnostic accuracy of soft tissue masses by ultrasonography and radiography was 100 % (42/42) and 71.4 % (30/42), respectively. The positive rate of ultrasonography and radiography in displaying bony changes was 53.3 % (24/45) and 97.8 % (44/45), respectively. In conclusion, in the detection of soft tissue mass of osteosarcoma, ultrasonography is superior to radiography, and in displaying bony changes of osteosarcomas, radiography is superior to ultrasonography. So it may come to a conclusion that plain radiography combined with ultrasonography can completely display the bony and soft tissue lesion of osteosarcomas.  相似文献   
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