***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: OBJECTIVES To compare the accuracy of transvaginal sonography ( TVS ) and magnetic resonance imaging ( MRI ) in the preoperative staging of endometrial carcinoma . METHODS This was a prospect i ve study in which 74 women consecutively diagnosed with endometrial carcinoma were examined using TVS by physicians trained in  gynecological sonography  and MRI by radiologists with a special interest in gynecology . All patients underwent surgical-pathological staging after removal of the uterus , adnexa and pelvic lymph nodes .  Sensitivity , specificity , and positive and negative predictive values were calculated for each imaging modality with regard to detection of neoplastic invasion of the outer half of the myometrium and cervical involvement . RESULTS TVS and MRI performed equally well in the preoperative staging of endometrial cancer , with no statistically significant differences between the two techniques . The sensitivity , specificity , positive and negative predictive values , and overall diagnostic accuracy for TVS in the evaluation of myometrial infiltration were 84 % , 83 % , 79 % , 88 % and 84 % , respectively . Respective values for  MRI  were 84 % , 81 % , 77 % , 87 % and 82 % . The corresponding statistics for detection of cervical involvement were 93 % , 92 % , 72 % , 98 % and 92 % for TVS ; and 79 % , 87 % , 58 % , 95 % and 85 % for MRI . CONCLUSIONS When carried out by expert practitioners , TVS shows good accuracy in the local staging of endometrial carcinoma . Because of its high costs , MRI should be offered only to those in whom TVS produces images of poor quality The depth of myometrial infiltration by endometrial cancer is an important prognostic factor . The examination of the depth of infiltration classifies the patients in the low- and high-risk groups , which influences the therapeutic approach . Transvaginal ultrasonography represents a first-choice diagnostic test for the assessment of the depth of myometrial infiltration as the time consumption and financial dem and s of magnetic resonance imaging need to be taken into account . In comparison with the MRI , the diagnostic accuracy of the transvaginal ultrasound depends more on the individual experience and professional potential of the examining physician . This fact can contribute to the heterogeneity of published results of transvaginal ultrasound on the determination of infiltration depth . Having in mind the aim to verify these indicators in our local conditions and environment , we decided to prospect ively study 150 endometrial cancer patients who were examined with the transvaginal ultrasound in the period 1/2009 - 10/ 2011 . Correlated firstly with the preoperative and then secondly with the definitive histopathological examination was the depth-of-infiltration-related data that had been taken from the ultrasound findings . The output being monitored was the exclusion or confirmation of the invasion exceeding half the thickness of myometrium . In our study , the diagnostic accuracy of the method reached 82.67 % , while the other indicators were as follows : sensitivity 92.31 % , specificity 79.28 % , positive predictive value ( PPV ) 61.02 % , negative predictive value ( NPV ) 96.7 % , the likelihood ratio of a positive test 4.455 and the likelihood ratio of a negative test 0.097 . The results of the depth of myometrial infiltration examination and their comparison with the data from similarly oriented clinical studies entitle us to include this examination in the set of st and ard preoperative methods used for the examination of patients with endometrial cancer ( Tab . 3 , Fig. 5 , Ref . 20 ) OBJECTIVE The purpose s of this study were to compare transvaginal sonography ( TVS ) , intraoperative sonography ( IOS ) , and gross visual inspection of the uterus with the histopathologic findings in patients with endometrioid adenocarcinoma , and to compare the accuracies of TVS , IOS , and gross visual inspection in staging of the tumor . SUBJECTS AND METHODS Sixteen patients with endometriod carcinoma were prospect ively evaluated with TVS and IOS . Intraoperative gross visual inspection was also performed . Gray-scale , duplex , and color Doppler findings were used to stage patients . The location and depth of myometrial invasion and the presence of cervical involvement were recorded . At gross visual inspection , only the absence or presence and the depth of myometrial invasion ( < or = 50 % or > 50 % ) were recorded . The data were analyzed three ways . First , in uterine specimens with myometrial invasion , a site-by-site comparison was made among the TVS and IOS findings and the final histologic results regarding location and depth of tumor invasion . Next , to determine tumor stage , myometrial invasion was defined in two ways : ( 1 ) absent , 50 % or less , or greater than 50 % ; and ( 2 ) 50 % or less or greater than 50 % . Then imaging findings , gross visual inspection , and the final histologic results were compared . RESULTS Of the 16 uterine specimens , eight had myometrial invasion , with 13 separate sites of tumor invasion . IOS correctly identified the location and depth ( + /- 10 % of the histologic depth ) of tumor invasion at four ( 31 % ) sites , and TVS at one ( 8 % ) site . TVS and IOS overestimated myometrial invasion due to adenomyosis , bulky intraluminal tumor , and lymphovascular invasion . When myometrial invasion was defined as absent , 50 % or less , or greater than 50 % , TVS was correct in 60 % of cases , IOS in 56 % , and gross visual inspection in 53 % . When myometrial invasion was defined as 50 % or less or greater than 50 % , TVS was correct in 93 % of cases , IOS in 81 % , and gross visual inspection in 80 % . CONCLUSION TVS and IOS are inaccurate in predicting the precise location and depth of myometrial tumor invasion . However , when a less rigorous definition of invasion is used , the accuracies of TVS and IOS are comparable to gross visual inspection in staging of the tumor OBJECTIVES To develop and vali date strategies , using new ultrasound-based mathematical models , for the prediction of high-risk endometrial cancer and compare them with strategies using previously developed models or the use of preoperative grading only . METHODS Women with endometrial cancer were prospect ively examined using two-dimensional ( 2D ) and three-dimensional ( 3D ) gray-scale and color Doppler ultrasound imaging .  More than 25 ultrasound , demographic and histological variables were analyzed . Two logistic regression models were developed : one ' objective ' model using mainly objective variables ; and one ' subjective ' model including subjective variables ( i.e. subjective impression of myometrial and cervical invasion , preoperative grade and demographic variables ) . The following strategies were vali date d : a one-step strategy using only preoperative grading and two-step strategies using preoperative grading as the first step and one of the new models , subjective assessment or previously developed models as a second step . RESULTS One-hundred and twenty-five patients were included in the development set and 211 were included in the validation set . The ' objective ' model retained preoperative grade and minimal tumor-free myometrium as variables . The ' subjective ' model retained preoperative grade and subjective assessment of myometrial invasion . On external validation , the performance of the new models was similar to that on the development set . Sensitivity for the two-step strategy with the ' objective ' model was 78 % ( 95 % CI , 69 - 84 % ) at a cut-off of 0.50 , 82 % ( 95 % CI , 74 - 88 % ) for the strategy with the ' subjective ' model and 83 % ( 95 % CI , 75 - 88 % ) for that with subjective assessment . Specificity was 68 % ( 95 % CI , 58 - 77 % ) , 72 % ( 95 % CI , 62 - 80 % ) and 71 % ( 95 % CI , 61 - 79 % ) respectively . The two-step strategies detected up to twice as many high-risk cases as preoperative grading only . The new models had a significantly higher sensitivity than did previously developed models , at the same specificity . CONCLUSION Two-step strategies with ' new ' ultrasound-based models predict high-risk endometrial cancers with good accuracy and do this better than do previously developed models OBJECTIVE A prospect i ve study was design ed to compare transvaginal sonography with contrast-enhanced MR imaging to determine preoperatively the depth of myometrial invasion in patients with early-stage endometrial carcinoma . SUBJECTS AND METHODS In 40 patients , findings on transvaginal sonograms , unenhanced T2-weighted MR images , and contrast-enhanced T1-weighted Mr images were compared with histologic findings . The depth of myometrial invasion was classified as stage E ( tumor limited to endometrium , n = 12 ) , stage S ( superficial invasion : tumor invades up to 50 % of the myometrium , n = 15 ) , or stage D ( deep invasion : tumor invades more than 50 % of the myometrium , n = 13 ) . RESULTS Findings on transvaginal sonograms were accurate in 27 of 40 patients ( accuracy , 68 % ) ; the depth of invasion was overestimated in five patients and underestimated in eight patients . The results of unenhanced T2-weighted MR images were accurate in 27 patients ( accuracy , 68 % ) , with four overestimations and nine underestimations . The results of contrast-enhanced T1-weighted MR images were accurate in 34 patients ( accuracy , 85 % ) , with five underestimations and one overestimation . In the assessment of each stage of myometrial invasion , the sensitivity and specificity of contrast-enhanced T1-weighted imaging were higher than those of T2-weighted MR imaging and transvaginal sonography . The false-positive diagnoses based on transvaginal sonograms and T2-weighted images , respectively , involved polypoid tumors ( n = 4 and 2 ) , distension of the endometrial cavity by pyometra ( n = 2 and 1 ) , the presence of myoma ( n = 2 and 1 ) , atrophy of the myometrium ( n = 1 and 0 ) , and poor tumor/myometrium contrast ( n = 0 and 2 ) . On contrast-enhanced MR images , accuracy was influenced only in a case of polypoid tumor , because tumor , endometrial cavity , and myometrium were clearly distinguished and residual myometrium was clearly visualized . With all imaging techniques , false-negative diagnoses were caused mainly by tumors with superficially spreading growth or microscopic invasion . With transvaginal sonography , infiltrative tumor also tended to be understaged ( n = 3 ) . CONCLUSION Contrast-enhanced MR imaging is significantly superior to transvaginal sonography and unenhanced T2-weighted MR imaging for detecting myometrial invasion In recent years , the incidence of carcinoma of the endometrium has shown an upward trend , such that it is currently the most frequently encountered malignant tumor of the female genital tract . An accurate preoperative diagnosis of the extent and spread of such carcinomas is of crucial importance for the selection of a therapeutic approach appropriate to the stage and infiltration of each particular tumor . In a prospect i ve study of 80 patients with a carcinoma of the endometrium , performed at the Department of Obstetrics and Gynecology of the University of Mainz , we compared the preoperative findings of transvaginal sonography with the postoperative histological results with respect to the following parameters : endometrial thickness , demarcation of the boundary of the endometrium , myometrial infiltration depth and staging . In all of these patients , sonography revealed a distinct increase in the thickness of the endometrium . In all cases , the structure of the endometrium was found to be heterogenous , with an irregular and poorly delineated boundary . Assessment s of the depth of tumor infiltration and the tumor staging obtained by  transvaginal sonography  were found to correlate with the histological findings in 85 % and 87.5 % of the cases , respectively . Thus , in cases of endometrial carcinoma , transvaginal sonography has an essential role to play in devising an individualized operative treatment program that takes into account the extent , spread and stage of the tumor OBJECTIVE To compare the ability of transvaginal sonography and serum CA 125 levels to predict myometrial invasion in patients with endometrial carcinoma . DESIGN AND METHODS Prospect i ve study in 50 consecutive patients ( mean age 60 years , SD 10.5 , range 29 - 77 years ) diagnosed as having endometrial cancer and scheduled for surgical staging . All patients were evaluated by transvaginal ultrasonography .  Endometrial thickness was measured in all cases and myometrial invasion was estimated as < 50 % or > or = 50 % . Serum CA 125 level was determined in each patient . A cut-off level of > or = 35 IU/ml was considered to predict myometrial invasion of > or = 50 % . All patients underwent surgical staging , and definitive histopathological findings regarding myometrial invasion were used as the ' gold st and ard ' . Sensitivity , specificity and positive predictive value ( PPV ) and negative predictive value ( NPV ) were calculated for transvaginal ultrasonography and CA 125 and compared . RESULTS On histopathological analysis 
    Output:
    
Diagnostic performance of TVS  for detecting deep myometrial infiltration in women with endometrial cancer is moderate