187,319 research outputs found
External validation of the preoperative Karakiewicz nomogram in a large multicentre series of patients with renal cell carcinoma
No full textTo perform a formal external validation of the preoperative Karakiewicz nomogram (KN) for the prediction of cancer-specific survival (CSS) using a large series of surgically treated patients diagnosed with organ-confined or metastatic renal cell carcinoma (RCC).
Patient population originated from a series of retrospectively gathered cases that underwent radical or partial nephrectomy between years 1995 and 2007 for suspicion of kidney cancer. The original Cox coefficients were used to generate the predicted risk of CSS at 1, 2, 5, and 10 years following surgery and compared to the observed risk of CSS in the current population. External validation was quantified using measures of predictive accuracy, defined as model discrimination and calibration.
A total of 3,374 patients were identified. Relative to the original development cohort, the current sample population had a larger proportion of patients with localized (40.0 vs. 26.3 %, P < 0.001) and non-metastatic (92.2 vs. 88.1 %, P = 0.03) disease at presentation. Model discrimination for the prediction of CSS was 87.8 % (95 % CI, 84.4-91.4) at 1 year, 87.0 % (95 % CI, 84.4-89.5) at 2 years, 84.7 % (95 % CI, 82.3-87.1) at 5 years, and 85.9 % (95 % CI, 83.2-88.6) at 10 years. The relationship between predicted and observed CSS risk was adequate in the calibration plot.
The use of the KN for the prediction of CSS in patients diagnosed with renal cell carcinoma was validated in the current study. In consequence, this tool may be recommended for routine clinical counseling in patients with various stages of RCC in the preoperative setting
Reply to Michael Staehler's Letter to the Editor re: Pierre I Karakiewicz, Nazareno Suardi, Claudio Jeldres, et al. Neoadjuvant Sutent Induction Therapy May Effectively Down-Stage Renal Cell Carcinoma Atrial Thrombi. Eur Urol 2008;53:845-848
No full textExternal validation of the preoperative Karakiewicz nomogram in a large multicentre series of patients with renal cell carcinoma
No full textPURPOSE:
To perform a formal external validation of the preoperative Karakiewicz nomogram (KN) for the prediction of cancer-specific survival (CSS) using a large series of surgically treated patients diagnosed with organ-confined or metastatic renal cell carcinoma (RCC).
METHODS:
Patient population originated from a series of retrospectively gathered cases that underwent radical or partial nephrectomy between years 1995 and 2007 for suspicion of kidney cancer. The original Cox coefficients were used to generate the predicted risk of CSS at 1, 2, 5, and 10 years following surgery and compared to the observed risk of CSS in the current population. External validation was quantified using measures of predictive accuracy, defined as model discrimination and calibration.
RESULTS:
A total of 3,374 patients were identified. Relative to the original development cohort, the current sample population had a larger proportion of patients with localized (40.0 vs. 26.3 %, P < 0.001) and non-metastatic (92.2 vs. 88.1 %, P = 0.03) disease at presentation. Model discrimination for the prediction of CSS was 87.8 % (95 % CI, 84.4-91.4) at 1 year, 87.0 % (95 % CI, 84.4-89.5) at 2 years, 84.7 % (95 % CI, 82.3-87.1) at 5 years, and 85.9 % (95 % CI, 83.2-88.6) at 10 years. The relationship between predicted and observed CSS risk was adequate in the calibration plot.
CONCLUSION:
The use of the KN for the prediction of CSS in patients diagnosed with renal cell carcinoma was validated in the current study. In consequence, this tool may be recommended for routine clinical counseling in patients with various stages of RCC in the preoperative settin
Assessing the accuracy and generalizability of the preoperative and postoperative Karakiewicz nomograms for renal cell carcinoma: results from a multicentre European and US study.
No full textTo assess the accuracy and generalizability of the pre- and postoperative Karakiewicz nomograms for predicting cancer-specific survival (CSS) in patients with renal cell carcinoma (RCC). This retrospective study included 3231 patients from European and US centres, who were treated by radical or partial nephrectomy for RCC between 1992 and 2010. Prognostic scores for each patient were calculated and the primary endpoint was CSS. Discriminating ability was assessed by Harrell's c-index for censored data. The 'validation by calibration' method proposed by Van Houwelingen was used for checking the calibration of covariate effects. Calibration was graphically explored. Local and systemic symptoms were present in 23.2% and 9.1% of the patients, respectively. The median follow-up (FU) was 49 months. At the last FU, 408 cancer-related deaths were recorded, Kaplan-Meier estimates of CSS (with 95% confidence intervals [CIs]) at 5 and 10 years were 0.86 (0.84-0.87) and 0.77 (0.75-0.80), respectively. Both nomograms discriminated well. Stratified c-indices for CSS were 0.784 (95% CI 0.753-0.814) for the preoperative nomogram, and 0.842 (95% CI 0.816-0.867) for the postoperative one, with a significant difference between the two values (P < 0.001). The covariate-based predictions on our data for both nomograms were valid. The calibration plots showed no relevant departures from ideal predictions. The results suggest that the postoperative Karakiewicz nomogram discriminates substantially better than the preoperative one. These nomogram-based predictions may be used as benchmark data for pretreatment and postoperative decision-making in patients at various stages of RCC. © 2013 BJU International
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Neoadjuvant sutent induction therapy may effectively down-stage renal cell carcinoma atrial thrombi
No full textA 75-yr-old previously healthy woman presented with gross hematuria, European Cooperative Oncology Group 0, and an 11-cm renal mass with right atrial thrombus. The patient refused the sternotomy. She was offered two cycles of sunitinib maleate (Sutent) induction therapy to down-stage the thrombus and to reduce the extent of the surgery. (C) 2007 European Association of Urology. Published by Elsevier B.V. All rights reserved
The effect of comorbidities and socioeconomic status on sexual and urinary function in men undergoing prostate cancer screening
No full textIntroduction. Comorbidities and socioeconomic status (SES) represent known confounders of baseline health-related quality of life. Aim. To assess the effect of comorbidities and of SES variables on urinary function (UF) and sexual function (SF) and on associated bother items. Methods. A cohort of 1,162 men without an established diagnosis of prostate cancer (PCa) completed questionnaires addressing SES characteristics, the lifetime prevalence of 12 comorbid conditions, SF and UF as well as their associated bother. Main Outcome Measures. Crude and adjusted logistic regression models tested the association between the predictors, SES and comorbidity, and four separate outcomes, namely SF and UF and their associated bother. Results. Of all men, aged 40-79 years, 172 (14.8%) reported poor or very poor ability to have an erection, and for 165 (14.2%), erectile function (EF) was a big or moderate problem. Daily or weekly urinary incontinence was reported by 98 (8.4%) men, and for 94 (8.1%) men, UF was a big or moderate problem. One or more comorbidities were present in 437 (37.6%) men. In age- and SES-adjusted analyses, major depression and diabetes had the most detrimental effect on EF (5.8 [P < 0.001] and 4.8 [P < 0.001], respectively) and on sexual bother (4.3 [P < 0.001] and 7.2 [P < 0.001], respectively). Stroke (4.7 [P = 0.004]) and drug problems (4.8 [P = 0.002]) had the most detrimental effect on urinary incontinence. Alcoholism and alcohol-related problems (3.1 [P = 0.004]) had the most detrimental effect on the urinary bother scale. Finally, SES only affected urinary incontinence, which was poorer in men who lived with a spouse or partner (2.1 [P = 0.03]). Conclusion. Select comorbidities have very strong effects on UF and EF. Conversely, for most SES variables, the effect was weak and insignificant. In consequence, when patients are assessed for definitive PCa therapy, comorbidities require an adjustment, whereas SES assessment may potentially be omitted, especially if questionnaire brevity is a consideration
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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