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91.
92.
PURPOSE: A prior report suggested that radical prostatectomy may confer a survival advantage to patients with metastatic castration recurrent prostate cancer. Therefore, a pooled analysis of 9 trials performed by Cancer and Leukemia Group B was done to determine if men with metastatic castration recurrent prostate cancer who underwent prior prostatectomy had improved clinical outcomes, such as overall, prostate specific, progression-free and PSA progression-free survival, than men who did not undergo prior prostatectomy. MATERIALS AND METHODS: Data from 9 multi-institutional trials performed by Cancer and Leukemia Group B were combined. Eligible patients had progressive prostate cancer during androgen deprivation therapy, Eastern Cooperative Oncology Group performance status 0-2, and adequate hematological, renal and hepatic functions. The proportional hazards model was used to assess the prognostic importance of radical prostatectomy for predicting clinical outcomes. RESULTS: Of 1,238 men 310 (25%) underwent prostatectomy. Median survival was 14.7 (95% CI 12.9-16.7) and 14.5 months (95% CI 13.5-15.7) in men who did and did not undergo prostatectomy, respectively. The HR for death was 1.03 (95% CI 0.90-1.19, p = 0.65) in men with vs without prostatectomy. CONCLUSIONS: Prior prostatectomy in men with metastatic castration recurrent prostate cancer who were subsequently enrolled on clinical trials for cancer treatment had similar survival compared to men who did not undergo prior prostatectomy. These data do not support another report suggesting that prior prostatectomy confers a subsequent survival advantage in men with castration recurrent prostate cancer.  相似文献   
93.
For decades, options for the treatment for metastatic renal cancer have been limited and mostly ineffective. During this time, immunotherapy agents, such as IFN-alpha and IL-2, have represented the major treatment options. Over the last 3 years, advances in cancer biology have characterized important signaling pathways that regulate blood vessel growth and cell proliferation. These studies have identified a number of novel 'druggable' targets. Since 2004, this has resulted in regulatory approval of four additional agents that are active against renal cancer (bevacizumab, sorafenib, sunitinib and temsirolimus). A large number of additional candidate molecules that block the vascular endothelial growth factor and mTOR pathways have subsequently been identified. These agents are rapidly progressing through clinical testing in renal cancer and in other malignancies. This paper overviews the status of these investigational agents and anticipates areas of future research and development.  相似文献   
94.
OBJECTIVE: Catheter-based intraarterial injections of gadolinium are useful during MR imaging-guided endovascular procedures to generate rapid vascular road maps. Using an animal model of renal artery stenosis, we tested the hypothesis that intraarterial gadolinium-enhanced MR angiography is as accurate as IV gadolinium-enhanced MR angiography and digital subtraction angiography (DSA). We also tested the hypothesis that intraarterial MR angiography uses less gadolinium than IV MR angiography. MATERIALS AND METHODS: We induced bilateral renal artery stenosis in five pigs. All pigs underwent comparative imaging with DSA, IV MR angiography, and aortic catheter-directed intraarterial MR angiography. For IV and intraarterial MR angiography, we used the same three-dimensional acquisition. We assessed differences in quantitative stenosis measurements among DSA, IV MR angiography, and intraarterial MR angiography using the Wilcoxon's signed rank test. RESULTS: Mean stenosis measurements (+/-SD) were as follows: DSA, 58% +/- 12%; IV MR angiography, 63% +/- 9.3%; and intraarterial MR angiography, 64% +/- 11%. There were no statistically significant differences in accuracy between DSA and IV MR angiography (p = 0.06), DSA and intraarterial MR angiography (p = 0.16), or IV and intraarterial MR angiography (p = 0.70). Intraarterial MR angiography used a mean gadolinium dose of 5.6 mL, compared with 9 mL for IV MR angiography. CONCLUSION: In swine, IV and intraarterial MR angiography have a similar accuracy for detecting renal artery stenosis. Intraarterial MR angiography uses smaller doses of injected gadolinium.  相似文献   
95.
Controversy currently exists over the use of CT versus aortography in initial evaluation of blunt chest trauma. A case is described in which CT expeditiously diagnosed cardiac rupture and ruled out aortic trauma.  相似文献   
96.
The prognostic value of the pathological response to combination chemotherapy of deeply invasive transitional cell cancer of the bladder was retrospectively assessed in 147 patients. Data were collected from 8 different centers. Patients were eligible if they had received intravenous combination chemotherapy followed by partial, total or radical cystectomy, and if they had a minimum followup of 2 years after the start of chemotherapy. Of the patients 90% received methotrexate, vinblastine, doxorubicin and cisplatin (M-VAC) or cisplatin plus methotrexate for a median of 3 courses (range 1 to 6). Of the 83 patients who were alive at analysis actuarial median followup was 30.5 months (range 13.2 to 85.6 months). A major pathological response (stage P0, Pis, Pa or P1) was achieved in 41.5% of the patients. Patients with a major pathological response (p stage less than 2) had a 5-year survival of 75% in contrast to 20% for the remaining nonresponding patients (p stage 2 or more). The survival of patients with a major pathological response was independent of whether the response was induced by 2 or more courses of chemotherapy, or whether it was induced by M-VAC in comparison with cisplatin plus methotrexate. Preoperative clinical assessments can identify nonresponding patients correctly and in these cases alternative treatment programs are required, since 80% will die of the disease. Moreover, if neoadjuvant chemotherapy is proved to increase survival, the data emphasize the importance of the response rate of the primary tumor and the need to investigate the optimal number of courses to induce the best response, preferably in the individual patient.  相似文献   
97.
PURPOSE: The Testicular Cancer Intergroup Study (TCIS) was undertaken to evaluate the pathologic findings in early-stage testicular cancer as determined by central pathology review, to compare these findings with the interpretation by the contributing pathologists, and to make correlations with various clinical parameters and outcomes. PATIENTS AND METHODS: The prospective study of non-seminomatous germ cell testicular cancer staged surgically involved 459 eligible patients with stage I (node-negative) or stage II (node-positive) disease. Pathologic materials from both the orchiectomy and lymphadenectomy specimens were submitted to a central laboratory for evaluation. RESULTS: Central and local pathologists differed significantly in their identification of certain cellular histologies (primarily yolk sac tumors [YST]) and recognition of invasion into vascular structures. In contrast to our prior findings with local pathologic assessment, venous/lymphatic invasion as determined by central review predicted relapse in both stages. In pathologic stage I disease, the relapse rate was 19.4% (12 of 62 cases) for those with invasion versus 6.0% (10 of 168 cases) for those without invasion. In pathologic stage II disease, the respective relapse rates were 63.5% (40 of 63 cases) and 24.0% (six of 25 cases). Vascular invasion was jointly predictive with nodal stage for risk of relapse. The percentage of embryonal carcinoma (EC) in the primary tumor was predictive of nodal stage and relapse in a univariate, but not a multivariate, analysis. In a large substudy, immunohistochemical staining identified a correlation between stain intensity in YST and serum alpha-fetoprotein (AFP) levels. In a similar fashion human chorionic gonadotropin (HCG) staining reactivity occurred exclusively in patients with syncytiotrophoblasts and correlated with serum levels of beta-HCG. CONCLUSIONS: A number of tumor histology correlates with clinical parameters have been identified or confirmed. Careful pathologic scrutiny of the primary testicular tumor, especially for vascular invasion, provides important prognostic information.  相似文献   
98.
Summary. Background: Recent studies indicate that arterial cardiovascular diseases and venous thromboembolism (VTE) share common risk factors. A family history of myocardial infarction (MI) is a strong and independent risk factor for future MI. Objectives: The purpose of the present study was to determine the impact of cardiovascular risk factors, including family history of MI, on the incidence of VTE in a prospective, population‐based study. Patients and methods: Traditional cardiovascular risk factors and family history of MI were registered in 21 330 subjects, aged 25–96 years, enrolled in the Tromsø study in 1994–95. First‐lifetime VTE events during follow‐up were registered up to 1 September 2007. Results: There were 327 VTE events (1.40 per 1000 person‐years), 138 (42%) unprovoked, during a mean of 10.9 years of follow‐up. In age‐ and gender‐adjusted analysis, age [hazard ratio (HR) per decade, 1.97; 95% confidence interval (CI), 1.82–2.12], gender (men vs. women; HR, 1.25; 95% CI, 1.01–1.55), body mass index (BMI; HR per 3 kg m?2, 1.21; 95% CI, 1.13–1.31), and family history of MI (HR, 1.31; 95% CI, 1.04–1.65) were significantly associated with VTE. Family history of MI remained a significant risk factor for total VTE (HR, 1.27; 95% CI, 1.01–1.60) and unprovoked VTE (HR, 1.46; 95% CI, 1.03–2.07) in multivariable analysis. Blood pressure, total cholesterol, HDL‐cholesterol, triglycerides, and smoking were not independently associated with total VTE. Conclusions: Family history of MI is a risk factor for both MI and VTE, and provides further evidence of a link between venous and arterial thrombosis.  相似文献   
99.
The objective was to produce a cascade of care for Catalonia to gain a public health perspective on the overall quality of HIV services and allow comparison with other countries. It was constructed using the Integrated Epidemiological Surveillance System of HIV in Catalonia and data from the PISCIS Cohort. Estimates of the number of people living with HIV in Catalonia are modelled using Spectrum Projection Package 2011 (UNAIDS/WHO). Totals for each stage in the cascade are obtained by applying to the preceding stage a proportion estimated from available surveillance and cohort data. Undiagnosed HIV was estimated from the European literature. The proportions retained in care, on ART and virally suppressed were derived from the PISCIS cohort. Programmatic data on ART consumption was used to validate estimates. By the end of 2011 there were about 33,000 people living with HIV in Catalonia, 71% of which had been both diagnosed and linked to care. We estimate that 61% of all HIV infected persons were retained in care, 56% were on ART and 48% were virally suppressed. These figures data are comparable, although slightly lower, than that of France or the UK. The Cascade of HIV Care in Catalonia is similar to other western European countries such as France and the UK. Direct estimates of the undiagnosed HIV population and linkage to care are desirable but the contribution of cohort data to the cascade highlights their continued importance in HIV surveillance and design of evidence-based health strategies.  相似文献   
100.

Background and Rationale:

Ensuring research participants’ autonomy is one of the core ethical obligations of researchers. This fundamental principle confers on every participant the right to refuse to take part in clinical research, and the measure of the number of consent refusals could be an important metric to evaluate the quality of the informed consent process. This audit examined consent refusals among Indian participants in clinical studies done at our center.

Materials and Methods:

The number of consent refusals and their reasons in 10 studies done at our center over a 5-year period were assessed. The studies were classified by the authors according to the type of participant (healthy vs patients), type of sponsor (investigator-initiated vs pharmaceutical industry), type of study (observational vs interventional), level of risk [based on the Indian Council of Medical Research (ICMR) “Ethical Guidelines for Biomedical Research on Human Participants”], available knowledge of the intervention being studied, and each patient''s disease condition.

Results:

The overall consent refusal rate was 21%. This rate was higher among patient participants [23.8% vs. healthy people (14.9%); P = 0.002], in interventional studies [33.6% vs observational studies (7.5%); P < 0.0001], in pharmaceutical industry-sponsored studies [34.7% vs investigator-initiated studies (7.2%); P < 0.0001], and in studies with greater risk (P < 0.0001). The most common reasons for consent refusals were multiple blood collections (28%), inability to comply with the study protocol (20%), and the risks involved (20%).

Conclusion:

Our audit suggests the adequacy and reasonable quality of the informed consent process using consent refusals as a metric.KEY WORDS: Autonomy, consent, India, reason, refusal, risk  相似文献   
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