***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: CONTEXT Three fourths of US men older than 50 years have been screened with prostate-specific antigen ( PSA ) for prostate cancer . OBJECTIVE To estimate the receiver operating characteristic ( ROC ) curve for PSA . DESIGN , SETTING , AND PARTICIPANTS Calculation of PSA ROC curves in the placebo group of the Prostate Cancer Prevention Trial , a r and omized , prospect i ve study conducted from 1993 to 2003 at 221 US centers . Participants were 18 882 healthy men aged 55 years or older without prostate cancer and with PSA levels less than or equal to 3.0 ng/mL and normal digital rectal examination results , followed up for 7 years with annual PSA measurement and digital rectal examination .  If PSA level exceeded 4.0 ng/mL or rectal examination result was abnormal , a prostate biopsy was recommended . After 7 years of study participation , an end-of- study prostate biopsy was recommended in all cancer-free men . MAIN OUTCOME MEASURES Operating characteristics of PSA for prostate cancer detection , including sensitivity , specificity , and ROC curve . RESULTS Of 8575 men in the placebo group with at least 1 PSA measurement and digital rectal examination in the same year , 5587 ( 65.2 % ) had had at least 1 biopsy ; of these , 1225 ( 21.9 % ) were diagnosed with prostate cancer . Of 1213 cancers with Gleason grade recorded , 250 ( 20.6 % ) were Gleason grade 7 or greater and 57 ( 4.7 % ) were Gleason grade 8 or greater . The areas under the ROC curve ( AUC ) for PSA to discriminate any prostate cancer vs no cancer , Gleason grade 7 or greater cancer vs no or lower- grade cancer , and Gleason grade 8 or greater cancer vs no or lower- grade cancer were 0.678 ( 95 % confidence interval [ CI ] , 0.666 - 0.689 ) , 0.782 ( 95 % CI , 0.748 - 0.816 ) , and 0.827 ( 95 % CI , 0.761 - 0.893 ) , respectively ( all P values < .001 for AUC vs 50 % ) . For detecting any prostate cancer , PSA cutoff values of 1.1 , 2.1 , 3.1 , and 4.1 ng/mL yielded sensitivities of 83.4 % , 52.6 % , 32.2 % , and 20.5 % , and specificities of 38.9 % , 72.5 % , 86.7 % , and 93.8 % , respectively . Age-stratified analyses showed slightly better performance of PSA in men younger than 70 years vs those 70 years or older with AUC values of 0.699 ( SD , 0.013 ) vs 0.663 ( SD , 0.013 ) ( P = .03 ) . CONCLUSION There is no cutpoint of PSA with simultaneous high sensitivity and high specificity for monitoring healthy men for prostate cancer , but rather a continuum of prostate cancer risk at all values of PSA BACKGROUND Although the first laparoscopic radical prostatectomy was performed in 1997 , few midterm oncologic data have been published for the extraperitoneal procedure . OBJECTIVE To determine the oncologic outcome of extraperitoneal laparoscopic radical prostatectomy ( ELRP ) . DESIGN , SETTING , AND PARTICIPANTS From 2000 to 2007 , 1115 consecutive patients underwent ELRP for a localized prostate cancer at our department . Follow-up was scheduled and st and ardized for all patients and recorded into a prospect i ve data base . Median postoperative follow-up was 35.6 mo . INTERVENTION All ELRP were performed by three surgeons at the Department of Urology , Hospital Henri Mondor , Créteil , France . MEASUREMENTS Biochemical recurrence was defined by prostate-specific antigen level > or = 0.2 ng/ml . RESULTS AND LIMITATIONS In pN0/pNx cancers , postoperative stage was pT2 in 664 patients ( 59.5 % ) , pT3 in 350 patients ( 31.4 % ) , and pT4 in 77 patients ( 6.9 % ) . Positive lymph nodes were reported in 24 patients ( 2.2 % ) . Margins were positive in 16.1 % and 34.6 % of pT2 and pT3 cancers , respectively . Final Gleason score was < 7 in 288 men ( 25.8 % ) , = 7 in 701 men ( 62.9 % ) , and > 7 in 126 men ( 11.3 % ) . Overall prostate-specific antigen ( PSA ) recurrence-free survival was 83 % at 5 yr . The 5-yr progression-free survival rates were 93.4 % for pT2 , 74.5 % for pT3a , and 55.0 % for pT3b tumors , respectively . Multivariate Cox model showed that PSA , Gleason score , pT category , nodal status , and surgical margins were significant independent predictors of biochemical recurrence-free survival . CONCLUSIONS This assessment of oncologic results demonstrates that ELRP is a safe and effective procedure . On the basis of midterm follow-up data , the prognostic factors of PSA after ELRP failure are the same as those described previously in transperitoneal or open retropubic approaches . The oncologic results of ELRP also are in line with those reported with the use of the retropubic or the transperitoneal laparoscopic approaches PURPOSE To prospect ively evaluate multiparametric magnetic resonance imaging ( MRI ) for accurate localization of intraprostatic tumor nodules , with whole-mount histopathology as the gold st and ard . MATERIAL S AND METHODS Seventy-five patients with biopsy-proven , intermediate , and high-risk prostate cancer underwent preoperative T2-weighted ( T2w ) , dynamic contrast-enhanced ( DCE ) and diffusion-weighted ( DW ) MRI at 1.5 T . Localization of suspicious lesions was recorded for each of 24 st and ardized regions of interest on the different MR images and correlated with the pathologic findings . Generalized estimating equations ( GEE ) were used to estimate the sensitivity , specificity , accuracy , positive , and negative predictive value for every MRI modality , as well as to evaluate the influence of Gleason score and pT-stage . Tumor volume measurements on histopathological specimens were correlated with those on the different MR modalities ( Pearson correlation ) . RESULTS DW MRI had the highest sensitivity for tumor localization ( 31.1 % vs. 27.4 % vs. 44.5 % for T2w , DCE , and DW MRI , respectively ; P < 0.005 ) , with more aggressive or more advanced tumors being more easily detected with this imaging modality . Significantly higher sensitivity values were obtained for the combination of T2w , DCE , and DW MRI ( 58.8 % ) as compared to each modality alone or any combination of two modalities ( P < 0.0001 ) . Tumor volume can most accurately be assessed by means of DW MRI ( r = 0.75 ; P < 0.0001 ) . CONCLUSION Combining T2w , DCE , and DW imaging significantly improves prostate cancer localization PURPOSE The biology of prostate cancer may be influenced by the index lesion . The definition of index lesion volume is important for appropriate decision making , especially for image guided focal treatment . We determined the accuracy of magnetic resonance imaging for determining index tumor volume compared with volumes derived from histopathology . MATERIAL S AND METHODS We evaluated 135 patients ( mean age 59.3 years ) with a mean prostate specific antigen of 6.74 ng/dl who underwent multiparametric 3 T endorectal coil magnetic resonance imaging of the prostate and subsequent radical prostatectomy .  Index tumor volume was determined prospect ively and independently by magnetic resonance imaging and histopathology . The ellipsoid formula was applied to determine histopathology tumor volume , whereas manual tumor segmentation was used to determine magnetic resonance tumor volume . Histopathology tumor volume was correlated with age and prostate specific antigen whereas magnetic resonance tumor volume involved Pearson correlation and linear regression methods . In addition , the predictive power of magnetic resonance tumor volume , prostate specific antigen and age for estimating histopathology tumor volume ( greater than 0.5 cm(3 ) ) was assessed by ROC analysis . The same analysis was also conducted for the 1.15 shrinkage factor corrected histopathology data set . RESULTS There was a positive correlation between histopathology tumor volume and magnetic resonance tumor volume ( Pearson coefficient 0.633 , p < 0.0001 ) , but a weak correlation between prostate specific antigen and histopathology tumor volume ( Pearson coefficient 0.237 , p = 0.003 ) . On linear regression analysis histopathology tumor volume and magnetic resonance tumor volume were correlated ( r(2 ) = 0.401 , p < 0.00001 ) . On ROC analysis AUC values for magnetic resonance tumor volume , prostate specific antigen and age in estimating tumors larger than 0.5 cm(3 ) at histopathology were 0.949 ( p < 0.0000001 ) , 0.685 ( p = 0.001 ) and 0.627 ( p = 0.02 ) , respectively . Similar results were found in the analysis with shrinkage factor corrected tumor volumes at histopathology . CONCLUSIONS Magnetic resonance imaging can accurately estimate index tumor volume as determined by histology . Magnetic resonance imaging has better accuracy in predicting histopathology tumor volume in tumors larger than 0.5 cm(3 ) than prostate specific antigen and age . Index tumor volume as determined by magnetic resonance imaging may be helpful in planning treatment , specifically in identifying tumor margins for image guided focal therapy and possibly selecting better active surveillance c and i date A variety of malignant neoplasms have been shown to induce capillary neovascularization , and in some cases the degree of vascularization appears to correlate with aggressive behavior and risk of metastasis . We hypothesized that carcinoma of the prostate also induces the formation of new capillaries , and we developed a method to quantify the relative density of microscopic vessels in carcinoma of the prostate compared with benign prostatic gl and ular tissue . The number of microvessel profiles in tissue sections was quantified by marking the vascular endothelial cells with antibodies to factor VIII-related antigen using st and ard immunohistochemistry techniques and comparing fields of adenocarcinoma with benign gl and ular tissue in 15 radical prostatectomy specimens . The analysis was facilitated by using the Optimas computerized image analysis system ( Bioscan , Seattle , WA ) with software written for this investigation . Fourteen of the 15 cases demonstrated significantly higher vascular density in the areas of carcinoma than in the benign tissues . Overall , the ratio of vessels per unit area in sections of carcinoma versus benign tissue was approximately double ( ratio = 2.02 ; P < .001 ) . In benign tissues the capillaries are restricted for the most part to the perigl and ular stroma immediately adjacent to the epithelium , whereas the distribution in carcinoma appears to be more r and om . The data demonstrate the increased density of capillaries in prostatic carcinoma when compared with benign prostate tissue BACKGROUND The prostate component of the Prostate , Lung , Colorectal , and Ovarian ( PLCO ) Cancer Screening Trial was undertaken to determine whether there is a reduction in prostate cancer mortality from screening using serum prostate-specific antigen ( PSA ) testing and digital rectal examination ( DRE ) . Mortality after 7 - 10 years of follow-up has been reported previously . We report extended follow-up to 13 years after the trial . METHODS A total of 76 685 men , aged 55 - 74 years , were enrolled at 10 screening centers between November 1993 and July 2001 and r and omly assigned to the intervention  ( organized screening of annual PSA testing for 6 years and annual DRE for 4 years ; 38 340 men ) and control ( usual care , which sometimes included opportunistic screening ; 38 345 men ) arms . Screening was completed in October 2006 . All incident prostate cancers and deaths from prostate cancer through 13 years of follow-up or through December 31 , 2009 , were ascertained . Relative risks ( RRs ) were estimated as the ratio of observed rates in the intervention and control arms , and 95 % confidence intervals ( CIs ) were calculated assuming a Poisson distribution for the number of events . Poisson regression modeling was used to examine the interactions with respect to prostate cancer mortality between trial arm and age , comorbidity status , and pretrial PSA testing . All statistical tests were two-sided . RESULTS Approximately 92 % of the study participants were followed to 10 years and 57 % to 13 years . At 13 years , 4250 participants had been diagnosed with prostate cancer in the intervention arm compared with 3815 in the control arm . Cumulative incidence rates for prostate cancer in the intervention and control arms were 108.4 and 97.1 per 10 
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These use quantitative elasticity values to differentiate benign from malignant areas of the prostate .
This method of assessment has shown that the elasticity changes for differing Gleason grade s and T stages of disease within the prostate .
Quantitative elasticity values offer the potential of using ' threshold ' elasticity values under which the prostate is benign .
Tissue elasticity has great potential as a diagnostic and prognostic biomarker for prostate cancer and can be assessed using various methods .
Currently transrectal sonoelastography has the most evidence supporting its use in clinical practice