Renal Recovery After Liver Transplantation Alone in Patients With Liver Cirrhosis and Severe Chronic Kidney Disease With Normal Kidney Size.

BACKGROUND: Most guidelines recommend simultaneous liver-kidney transplantation (SLKT) in patients with liver cirrhosis (LC) and severe chronic kidney disease (CKD) over liver transplantation alone (LTA). CKD, however, is not irreversible. This study evaluates the reversibility of kidney disease after LTA based on kidney size. MATERIALS AND METHODS: In this single-center retrospective study, we classified 90 patients with LC and severe CKD into 3 groups: the normal kidney (NK)-LTA group (n=39), small kidney (SK)-LTA group (both kidneys <9 cm at the time of LTA, n=40), and SK-SLKT group (n=11). RESULTS: The NK-LTA group had a lower percentage of hepatocellular carcinoma and a higher pre-liver transplantation (LT) estimated glomerular filtration rate. This group, however, was older, received livers from a higher percentage of deceased donors, and had a higher Child-Pugh score. Renal recovery, defined as the return of creatinine to their baseline, or a persistent change from baseline but not persistent (≥3 months) need for renal replacement therapy after LT, was found in 79% in the NK-LTA group, which was higher than 7.5% in the SK-LTA group. Renal and patient survival was found in 56% of the NK-LTA group, which was higher than 2.5% of the SK-LTA group. CONCLUSIONS: There is a high percentage of renal recovery in the NK-LTA group, and accordingly, this does not justify SLKT, since this would result in a "waste" of kidneys. Therefore, KT after LT is recommended over SLKT for the LC patients with NK size.

Characterization and PI-RADS version 2 assessment of prostate cancers missed by prebiopsy 3-T multiparametric MRI: Correlation with whole-mount thin-section histopathology.

OBJECTIVES: To determine the clinical and histopathologic characteristics of missed prostate cancers and their Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) score on a pre-biopsy MRI and subsequent MR-ultrasound (US) fusion biopsy. METHODS: We analysed 59 prostate cancer patients who underwent a 3-T MRI prior to an MR-US fusion biopsy and subsequent radical prostatectomy. A radiologist initially reviewed these cases to correlate target lesions and pathology-proven lesions. The patients were categorized as detected or missed prostate cancer cases. Three radiologists independently assigned the PI-RADS v2 score for each case. The missed lesions were further categorized as suspicious or invisible by consensus. The clinical characteristics, PI-RADS v2 scores, and histopathologic features were thereby obtained. RESULTS: Thirty seven (62.7%) of the 59 study cases had a detected prostate cancer and 22 (37.3%) as having missed cancer. Seventeen (77.3%) of the 22 missed patients had a clinically significant lesion. The missed cancer cases had a smaller tumour volume, and higher ADC ratio than the detected cancer cases. Fourteen (63.6%) of the missed lesions were not visible on MRI, even though 71.4% of these cancers were clinically significant. Invisible but clinically significant cancers had a tumour volume below 1 cm3 in 70% of cases. CONCLUSIONS: A negative MRI result does not rule out the current PI-RADS v2 definition of a clinically significant prostate cancer as these tumours can be missed if their volume is below 1 cm3.

Sonographic Features of Small (< 4 cm) Renal Tumors With Low Signal Intensity on T2-Weighted MR Images: Differentiating Minimal-Fat Angiomyolipoma From Renal Cell Carcinoma.

OBJECTIVE: The purpose of this study is to characterize and assess the diagnostic utility of sonographic features of minimal-fat angiomyolipoma (AML) and renal cell carcinoma (RCC) with regard to small (< 4 cm) renal masses with a predominantly low signal intensity (SI) on T2-weighted MR images. MATERIALS AND METHODS: Fifty small renal masses with a predominantly low SI on T2-weighted MR images and no macroscopic fat, all of which had US images available, were assessed. MRI variables (T2 ratio, signal intensity index [SII], and tumor-to-spleen ratio on chemical-shift images), CT features (enhancement patterns and attenuations values on unenhanced images and images obtained in the corticomedullary and nephrographic phases), and sonographic features (echogenicity, heterogeneity, and the presence of acoustic shadowing, a hypoechoic rim, or an intratumoral cyst) were recorded in a blinded manner. Echo-genicity was classified as hypo-, iso-, or hyperechoic compared with the renal parenchyma or markedly hyperchoic when equivalent to that of the renal sinus fat. RESULTS: Minimal-fat AML and RCC were confirmed in 22 and 28 patients, respectively. T2 ratios were significantly lower for minimal-fat AML versus RCCs (p = 0.044). Minimal-fat AMLs exhibited echogenicities that were considered hypoechoic (31.8%), isoechoic (4.5%), hyperechoic (18.2%), or markedly hyperechoic (45.5%). No RCC showed marked hyperechogenicity. CT attenuation values were significantly higher for the minimal-fat AMLs seen in all imaging phases. When the combination of the T2 ratio, nephrographic phase attenuation, and echogenicity was assessed, the AUC value was 0.93 (95% CI, 0.81-0.98), which was a significant increase over the AUC value of 0.83 (95% CI, 0.69-0.92) for noted the combination of the T2 ratio and nephrographic phase attenuation. CONCLUSION: Additional reviews of the echogenicity of small renal masses with low SI on T2-weighted MR images may aid the diagnosis of minimal-fat AML.

Gastric-Type Adenocarcinoma of the Uterine Cervix: Magnetic Resonance Imaging Features, Clinical Outcomes, and Prognostic Factors.

OBJECTIVE: Gastric-type mucinous adenocarcinoma (GAS) of uterine cervix has been suggested as distinct clinicopathologic behavior. Our study aimed to investigate the distinguishing imaging features and clinical outcomes of GAS. METHODS: Fifteen cases of GAS and 45 cases of 3:1 age-matched usual-type endocervical carcinoma (UEA) were assessed. Clinical parameters (age, tumor size, clinical stage, and time to recurrence [TTR] or death) and pathologic results confirmed by surgery were recorded. Imaging features (tumor shape, margin, presence of vaginal involvement, or cyst) on magnetic resonance T2-weighed images were evaluated by consensus reading. Parametrial invasion was assessed by 2 independent readers on a 4-point scale system. RESULTS: Gastric-type mucinous adenocarcinomas were associated with a higher stage at presentation and higher rates of deep cervical stromal invasion, parametrial invasion, and lymphovascular invasion. On magnetic resonance images, GASs also demonstrated a more infiltrative shape (93.3% vs 22.2%; P < 0.001) with/without cysts, ill-defined margin (93.3% vs 31.8%; P < 0.001), endocervical location (46.7%) or extension to the entire cervix (46.7%), higher rates of vaginal involvement (40.0% vs 4.4%; P = 0.002), and higher grade of parametrial invasion by both readers (66.7% vs 22.2%; P = 0.003) compared with UEAs. Patients with GAS had a significantly shorter TTR compared with UEA cases (P < 0.001) by log-rank test. A multivariate Cox proportional hazards model revealed that an infiltrative tumor shape (hazard ratio, 5.92; P = 0.004) and stage II or greater (hazard ratio, 4.19; P = 0.011) were prognostic indicators of a shorter TTR. CONCLUSIONS: Gastric-type mucinous adenocarcinoma may have characteristic imaging features and poorer outcomes compared with UEA.

The characteristics and spatial distributions of initially missed and rebiopsy-detected prostate cancers.

PURPOSE: The purpose of this study was to analyze the characteristics of initially missed and rebiopsy-detected prostate cancers following 12-core transrectal biopsy. METHODS: A total of 45 patients with prostate cancers detected on rebiopsy and 45 patients with prostate cancers initially detected on transrectal ultrasound-guided biopsy were included in the study. For result analysis, the prostate was divided into six compartments, and the cancer positive rates, estimated tumor burden, and agreement rates between biopsy and surgical specimens, along with clinical data, were evaluated. RESULTS: The largest mean tumor burden was located in the medial apex in both groups. There were significantly more tumors in this location in the rebiopsy group (44.9%) than in the control group (30.1%, P=0.015). The overall sensitivity of biopsy was significantly lower in the rebiopsy group (22.5% vs. 43.4%, P<0.001). The agreement rate of cancer positive cores between biopsy and surgical specimens was significantly lower in the medial apex in the rebiopsy group compared with that of the control group (50.0% vs. 65.6%, P=0.035). The cancer positive rates of target biopsy cores and premalignant lesions in the rebiopsy group were 63.1% and 42.3%, respectively. CONCLUSION: Rebiopsy-detected prostate cancers showed different spatial distribution and lower cancer detection rate of biopsy cores compared with initially diagnosed cancers. To overcome lower cancer detection rate, target biopsy of abnormal sonographic findings, premalignant lesions and medial apex which revealed larger tumor burden would be recommended when performing rebiopsy.

Does Computer-Aided Diagnosis Permit Differentiation of Angiomyolipoma Without Visible Fat From Renal Cell Carcinoma on MDCT?

OBJECTIVE: The purpose of this study was to evaluate the diagnostic value of computer-aided diagnosis (CADx) in differentiating angiomyolipoma without visible fat from renal cell carcinoma (RCC) on MDCT. MATERIALS AND METHODS: The study included 406 patients who had 47 angiomyolipomas without visible fat and 359 RCCs smaller than 4 cm, all of which were diagnosed on the basis of findings from nephrectomy or percutaneous biopsy performed at our institution between 2000 and 2011. MDCT (slice thickness, 2.5 mm for corticomedullary phase image or 5 mm for the other phase images) and clinical findings were blindly reviewed by two radiologists in a single session. At the time the study was performed, radiologist 1 had 8 years of experience, and radiologist 2 had 18 years of experience. On the basis of the MDCT and clinical findings, CADx classified renal tumors as angiomyolipoma and RCC, and each radiologist independently recorded the probability score (0-5) for angiomyolipoma. The accuracy of CADx versus radiologists in diagnosing angiomyolipoma was compared using ROC analysis. Interobserver agreement between the two radiologists was evaluated. RESULTS: CADx yielded an area under the curve (Az) value of 0.949, which was greater than the Az values yielded by radiologists 1 and 2 (0.872 and 0.782, respectively; p < 0.05). In addition, the Az value for radiologist 1 was greater than that for radiologist 2 (p = 0.01). CADx with a threshold of -1.0085 showed greater sensitivity than radiologist 1 and greater sensitivity, specificity, and accuracy than radiologist 2 (p < 0.05). The interobserver agreement for the differentiation was fair (κ = 0.289). CONCLUSION: CAD can improve diagnostic performance in differentiating angiomyolipoma from RCC. The diagnostic performance of radiologists is variable according to the clinical experience and physical and emotional states of the radiologists.

Diagnostic value of multidetector computed tomography for renal sinus fat invasion in renal cell carcinoma patients.

OBJECTIVE: Although renal sinus fat invasion has prognostic significance in patients with renal cell carcinomas (RCCs), there are no previous studies about the value of multidetector computed tomography (MDCT) about this issue in the current literature. MATERIALS AND METHODS: A total of 863 consecutive patients (renal sinus fat invasion in 110 patients (12.7%)) from single institutions with surgically-confirmed renal cell carcinoma who underwent MDCT between 2010 and 2012 were included in this study. The area under the curves (AUCs) of the receiver operating characteristic (ROC) analysis was used to compare diagnostic performance. Reference standard was pathologic examination. Weighted κ statistics were used to measure the level of interobserver agreement. Multivariate logistic regression model was used to find the predictors for renal sinus fat invasion. Image analysis was first performed with axial-only CT images. A second analysis was then performed with both axial and coronal CT images. A qualitative analysis was then conducted by two reviewers who reached consensus regarding tumor size, decreased perfusion, tumor margin, vessel displacement, and lymph node metastasis. The reference standard was pathologic evaluation. RESULTS: The AUCs of the ROC analysis were 0.881 and 0.922 for axial-only images and 0.889 and 0.902 for combined images in both readers. The AUC of tumor size was 0.884, a similar value to that of the reviewers. In multivariate analysis, tumor size, a linear-nodular or nodular type of fat infiltration, and an irregular tumor margin were independent predicting factors for perinephric fat invasion. CONCLUSION: MDCT shows relatively high diagnostic performance in detecting perinephric fat invasion of RCC but suffers from a relatively low PPV related to low prevalence of renal sinus fat invasion. Applying tumor size alone we could get similar diagnostic performance to those of radiologists. Tumor size, fat infiltration with a nodular appearance, and an irregular tumor margin were predictors for perinephric invasion.

The value of 15-minute delayed contrast-enhanced CT to differentiate hyperattenuating adrenal masses compared with chemical shift MR imaging.

OBJECTIVES: To investigate the diagnostic performance of 15-min delayed contrast-enhanced computed tomography (15-DECT) compared with that of chemical shift magnetic resonance (CSMR) imaging in differentiating hyperattenuating adrenal masses and to perform subgroup analysis in underlying malignancy and non-malignancy. METHODS: This study included 478 adrenal masses in 453 patients examined with 15-DECT and 235 masses in 217 patients examined with CSMR. Relative percentage washout (RPW) and absolute percentage washout (APW) on 15-DECT, and signal intensity index (SII) and adrenal-to-spleen ratio (ASR) on CSMR were measured. Sensitivity, specificity and accuracy of 15-DECT and CSMR were analysed for characterisation of adrenal adenoma. Subgroup analyses were performed in patients with and without underlying malignancy. Attenuation and size of the masses on unenhanced CT correlated with the risk of non-adenoma. RESULTS: RPW calculated from 15-DECT showed the highest diagnostic performance for characterising hyperattenuating adrenal masses regardless of underlying malignancy, and the sensitivity, specificity and accuracy were 91.7 %, 74.8 % and 88.1 %, respectively in all patients. The risk of non-adenoma increased approximately threefold as mass size increased 1 cm or as its attenuation value increased by 10 Hounsfield units. CONCLUSIONS: 15-DECT was more accurate than CSMR in characterising hyperattenuating adrenal masses regardless of underlying malignancy. KEY POINTS: Delayed contrast-enhanced CT and chemical shift magnetic resonance (CSMR) characterise adrenal lesions. 15-min DECT is more accurate than CSMR in characterising hyperattenuating adrenal masses. Sensitivity of CSMR decreases as the CT attenuation of adenomas increases. Risk of non-adenoma is increased 2.9-fold as size increased by 1 cm. Risk of non-adenoma is increased 2.9-fold as attenuation increased by 10 HU.

Predictors of unfavorable disease after radical prostatectomy in patients at low risk by D'Amico criteria: role of multiparametric magnetic resonance imaging.

PURPOSE: We identified risk factors predicting unfavorable pathological outcomes after radical prostatectomy in patients with low risk prostate cancer. We also evaluated the role of magnetic resonance imaging. MATERIALS AND METHODS: We retrospectively reviewed the medical records of 1,262 patients who underwent 12-core biopsy, preoperative magnetic resonance imaging and radical prostatectomy at a single center between September 2007 and June 2012. A total of 382 men with low risk prostate cancer by the D'Amico criteria were included in study. Multivariate logistic regression analysis was used to identify factors predicting unfavorable pathological outcomes. RESULTS: Median patient age was 65 years and median preoperative prostate specific antigen was 4.6 ng/ml. Gleason sum was upgraded in 212 patients (55.5%). In 249 patients (65.1%) prostate cancer was identified on 3 Tesla T2-weighted and diffusion-weighted magnetic resonance imaging without dynamic contrast imaging. The lesion was in the anterior and posterior of the prostate in 42.9% and 57.0% of cases, respectively. Unfavorable pathological results were found postoperatively in 29.6% of patients. Multivariate analysis revealed that older age (OR 1.072, p<0.001), number of positive cores (OR 1.373, p<0.001) and an anterior index tumor site on magnetic resonance imaging (OR 2.121, p=0.017) were significant predictors of unfavorable final pathological results (pT3 or greater, or tumor upgrading to Gleason 3+4 plus tumor volume 15% or greater, or upgrading to Gleason 4+3 or greater). CONCLUSIONS: An anterior site of cancer on magnetic resonance imaging was useful for predicting Gleason sum upgrading or an unfavorable pathological outcome after radical prostatectomy in patients with low risk prostate cancer.

Comparison of T2-weighted MRI with and without fat suppression for differentiating renal angiomyolipomas without visible fat from other renal tumors.

OBJECTIVE: The purpose of this study was to retrospectively compare the usefulness of T2-weighted imaging with and without fat suppression for differentiating angiomyolipomas (AMLs) without visible fat from other renal tumors. MATERIALS AND METHODS: MRI was performed in 111 patients (66 men and 46 women; age range, 17-78 years) who had pathologically diagnosed (14 AMLs, 86 renal cell carcinomas [RCCs], and three other tumors) and clinically diagnosed (eight AMLs) renal masses without visible fat or a cystic portion on unenhanced CT. The signal intensity (SI), tumor-to-kidney SI ratio, tumor-to-spleen SI ratio on T2-weighted imaging and fat-suppressed T2-weighted imaging, and tumor-fat subtraction index were measured for each tumor. Receiver operating characteristic (ROC) analysis was used to evaluate diagnostic accuracy of SI ratios. RESULTS: The highest area under the ROC curve was 0.886 for tumor-to-kidney SI ratio on fat-suppressed T2-weighted imaging. With a tumor-to-kidney SI ratio of 0.9 on fat-suppressed T2-weighted imaging, the sensitivity, specificity, positive predictive value, and negative predictive value were 90.9%, 71.1%, 43.5%, and 97%, respectively. The highest tumor-to-kidney SI ratio of AMLs without visible fat was 1.09. Ninety-eight percent of renal tumors with a tumor-to-kidney SI ratio greater than 1.09 were RCCs (51/52), especially clear cell RCCs (82.7%, 43/52). CONCLUSION: Fat-suppressed T2-weighted imaging is more useful than T2-weighted imaging for differentiating AMLs without visible fat from non-AMLs. The high SI of solid renal masses on fat-suppressed T2-weighted imaging can be indicative of non-AMLs, especially RCCs.

Diagnostic performance of multidetector computed tomography in the evaluation of perinephric fat invasion in renal cell carcinoma patients.

PURPOSE: This study aimed to evaluate the diagnostic performance of multidetector computed tomography (MDCT) for preoperative evaluation of perinephric fat invasion in patients with renal cell carcinomas (RCCs). METHODS: A total of 408 consecutive patients with surgically confirmed RCC who underwent MDCT were included in this study. Image analysis was first performed with axial-only CT images. A second analysis was then performed with both axial and coronal CT images. A qualitative analysis was then conducted by 2 reviewers who reached consensus. The reference standard was pathologic evaluation. RESULTS: The areas under the curve of the receiver operating characteristic analysis were 0.786 and 0.877 for axial-only images and 0.805 and 0.836 for combined images in both readers. The area under the curve of tumor size was 0.833, a similar value to that of the reviewers. In multivariate analysis, tumor size, a linear-nodular or nodular type of fat infiltration, and an irregular tumor margin were independent predicting factors for perinephric fat invasion. CONCLUSIONS: The MDCT shows relatively high diagnostic performance in detecting perinephric fat invasion of RCC, but suffers from a relatively low positive predictive value. Tumor size, fat infiltration with a nodular appearance, and an irregular tumor margin were predictors for perinephric invasion.

Three-phase, contrast-enhanced, multidetector CT in the evaluation of complicated renal cysts: comparison of the postcontrast phase combination.

BACKGROUND: Multiphasic multidetector computed tomography (MDCT) is widely used for the assessment and diagnosis of complicated renal cysts. PURPOSE: To determine the optimal combination of postcontrast phases of MDCT for the evaluation of complicated renal cysts. MATERIAL AND METHODS: In 164 renal cysts with pathology confirmation or follow-up >2 years, the Bosniak category was recorded by two radiologists in consensus. They reviewed the MDCT images during three interpretation sessions. In the first session, the radiologists evaluated two phases of images (unenhanced and corticomedullary phases), while during the second session, they evaluated two phases of images (unenhanced and parenchymal phases), and in the third session, they evaluated all three phases of images (unenhanced, corticomedullary, and parenchymal phases). The diagnostic accuracy for evaluating renal cysts was compared in each session using receiver-operating characteristics (ROC) analysis. RESULTS: There were 106 benign renal cysts and 58 malignant renal cysts. The areas under the ROC curves (AUCs) of the second and third sessions were greater than that of the first session (P < 0.05). The sensitivity, specificity, positive predictive value, and negative predictive value of the first session were 74%, 88%, 77%, and 86%, respectively, and those of the second session were 90%, 85%, 77%, and 94%, respectively. The values of the third session were identical to those of the second session. CONCLUSION: Unenhanced and parenchymal phase CT scans are sufficient for differentiating malignant from benign renal cysts and there was no additional value by adding the corticomedullary phase to the combination of unenhanced and parenchymal phase CT.

MDCT-based scoring system for differentiating angiomyolipoma with minimal fat from renal cell carcinoma.

BACKGROUND: Subtype-related various computed tomography (CT) features of renal cell carcinoma (RCC) are a confusing factor in differentiating angiomyolipoma with minimal fat (AMLmf) from RCC. To overcome RCC heterogeneity, a scoring system, which integrates multiple discrimitive parameters can be helpful for differentiating AMLmf from RCC. PURPOSE: To develop a MDCT-based scoring system for differentiating AMLmf from RCC. MATERIAL AND METHODS: In 407 patients with pathologically confirmed 48 AMLmfs and 359 RCCs (247 clear cell RCCs, 67 papillary RCCs, and 45 chromophobe RCCs), MDCT features (ratio of long-to-short diameter, enhancement characteristics, tumor attenuation on unenhanced scan, tumor margin, calcification), age, and sex were compared between AMLmf and RCCs. Based on logistic regression, a scoring system for diagnosing AMLmf over RCC was built, and its diagnostic accuracy was evaluated. RESULTS: Scores suggesting AMLmf, i.e. the logit function as used in logistic regression analysis, were calculated as follows: Score = e(6.16.A-0.003.B+1.20.C+0.97.D+2.13.E-0.05.F)/1+e(6.16.A-0.003.B+1.20.C+0.97.D+2.13.E-0.05.F), where A = ratio of long-to-short diameter, B = enhancement amount in early excretory phase, C = homogeneous enhancement, D = tumor attenuation on unenhanced scan, E = sex, and F = age. Area under receiver-operating characteristics curve of scoring system was 0.919. With a score of 0.204 or higher, the scoring system yielded greatest accuracy (90%, 368/407) for diagnosing AMLmf over RCC, which was greater than that of any single MDCT or clinical parameter (53-85%) (P < 0.05). With a score of 0.317 or higher, sensitivity and specificity were 68% (32/48) and 95% (340/359). CONCLUSION: MDCT-based scoring system can improve diagnostic performance of MDCT in differentiating AMLmf from RCC and help patients with AMLmf to avoid unnecessary surgery with high specificity.

Incremental value of magnetic resonance imaging for clinically high risk prostate cancer in 922 radical prostatectomies.

PURPOSE: We investigated the incremental value of magnetic resonance imaging in addition to clinical variables for predicting pathological outcomes and disease recurrence in patients with clinically high risk prostate cancer. MATERIALS AND METHODS: A total of 922 consecutive patients with clinically high risk prostate cancer underwent magnetic resonance imaging before radical prostatectomy. We created multivariate logistic regression and Cox proportional hazards models with clinical variables only or combined with magnetic resonance imaging data to predict pathological outcomes and biochemical recurrence. The models were compared using ROC curves and the Harrell concordance index. RESULTS: The proportion of patients with pathological extracapsular extension, seminal vesicle invasion and lymph node metastasis was 57.5%, 12.7% and 6.3%, respectively. The sensitivity and specificity of extracapsular extension, seminal vesicle invasion and lymph node metastasis detection were 43% and 84.2%, 34.9% and 93.8%, and 14.0% and 96.9%, respectively. The area under the ROC curve of the model with clinical variable and magnetic resonance imaging data was greater than that of the model with clinical variables alone to predict extracapsular extension and seminal vesicle invasion (0.734 vs 0.697, p=0.001 and 0.750 vs 0.698, p<0.001, respectively). The 5-year biochemical recurrence-free survival rate was 56.1%. To predict biochemical recurrence the concordance index of the multivariate model with clinical variables only and with clinical variables plus magnetic resonance imaging data was 0.563 and 0.599, respectively (p=0.003). CONCLUSIONS: Magnetic resonance imaging findings have incremental value in addition to clinical variables for predicting pathological outcomes and disease recurrence.

Radiologic-pathologic correlation of renal cell carcinoma associated with Xp11.2 translocation.

BACKGROUND: The prognosis of translocation RCCs in adult patients is relatively poor compared to that of other subtypes of RCCs. Although there have been several reports regarding radiologic findings of translocation RCC, studies with histologic correlation could help to understand the imaging features. PURPOSE: To explore the correlation between radiologic and pathologic findings in Xp11.2 translocation renal cell carcinoma (RCC) and provide clues for translocation RCC diagnosis. MATERIAL AND METHODS: CT scans of six patients (one man and five women; age range, 8-71 years; mean age, 34 years) with histologically-proven Xp11.2 translocation RCCs were retrospectively evaluated in consensus by two radiologists. Tumor size, presence of necrosis, hemorrhage, fat or calcification, enhancement patterns of the tumor, presence of lymphadenopathy, and distant metastases were evaluated. RESULTS: The average size of the tumors was 6 cm (range, 2.7-12 cm). All six tumors appeared as well-defined masses with areas of low attenuation representing hemorrhage or necrosis. Four tumors contained high attenuating solid portions, compared to the surrounding renal cortex seen on unenhanced images, where representing dense cellular component on microscopic examination. Peripheral rim enhancement pattern that correlated with histologic finding of a fibrous capsule was seen in five cases. In two patients who underwent kidney MR, the masses showed low signal intensity on T2-weighted images. One patient had lymphadenopathy. No distant metastasis was noted in any patient. CONCLUSION: Translocation RCC appeared as a well-defined mass that contain high attenuating solid portions on unenhanced images and low attenuating necrotic or hemorrhagic foci; the tumor also showed gradual peripheral rim enhancement due to a fibrous capsule surrounding the tumor.

Sonography of the adrenal glands in the adult.

Although its capability has been overlooked, sonography can be a useful screening tool for adrenal lesion in adults. In this article, we discuss scan technique, patient positioning, and anatomic consideration for adrenal sonography in adults and illustrate sonographic appearance of normal adrenal gland as well as adrenal tumors and tumor-like lesions.

Prostate cancer detection on dynamic contrast-enhanced MRI: computer-aided diagnosis versus single perfusion parameter maps.

OBJECTIVE: The purpose of this article is to assess the value of computer-aided diagnosis (CAD) for prostate cancer detection on dynamic contrast-enhanced MRI (DCE-MRI). MATERIALS AND METHODS: DCE-MRI examinations of 42 patients with prostate cancer were used to generate perfusion parameters, including baseline and peak signal intensities, initial slope, maximum slope within the initial 50 seconds after the contrast injection (slope(50)), wash-in rate, washout rate, time to peak, percentage of relative enhancement, percentage enhancement ratio, time of arrival, efflux rate constant from the extravascular extracellular space to the blood plasma (k(ep)), first-order rate constant for eliminating gadopentetate dimeglumine from the blood plasma (k(el)), and constant depending on the properties of the tissue and represented by the size of the extravascular extracellular space (A(H)). CAD for cancer detection was established by comprehensive evaluation of parameters using a support vector machine. The diagnostic accuracy of single perfusion parameters was estimated using receiver operating characteristic analysis, which determined threshold and parametric maps for cancer detection. The diagnostic performance of CAD for cancer detection was compared with those of T2-weighted imaging (T2WI) and single perfusion parameter maps, using histologic results as the reference standard. RESULTS: The accuracy, sensitivity, and specificity of CAD were 83%, 77%, and 77%, respectively, in the entire prostate; 77%, 91%, and 64%, respectively, in the transitional zone; and 89%, 89%, and 89%, respectively, in the peripheral zone. Values for k(ep), k(el), initial slope, slope(50), wash-in rate, washout rate, and time to peak showed greater area under the curve values (0.803-0.888) than did the other parameters (0.545-0.665) (p < 0.01) and were compared with values for CAD. In the entire prostate, accuracy was greater for CAD than for all perfusion parameters or T2WI (63-77%); sensitivity was greater for CAD than for T2WI, initial slope, wash-in rate, slope(50), and washout rate (38-77%); and specificity was greater for CAD than for T2WI, k(ep), k(el), and time to peak (59-68%) (p < 0.05). CONCLUSION: CAD can improve the diagnostic performance of DCE-MRI in prostate cancer detection, which may vary according to zonal anatomy.

Diagnosis of lymph node metastasis in uterine cervical cancer: usefulness of computer-aided diagnosis with comprehensive evaluation of MR images and clinical findings.

BACKGROUND: Lymph node (LN) status is an important parameter for determining the treatment strategy and for predicting the prognosis for patients with uterine cervical cancer. Computer-aided diagnosis (CAD) can be feasible for differentiating metastatic from non-metastatic lymph nodes in patients with uterine cervical cancer. PURPOSE: To determine the usefulness of CAD that comprehensively evaluates MR images and clinical findings for detecting LN metastasis in uterine cervical cancer. MATERIAL AND METHODS: In 680 LNs from 143 patients who underwent radical hysterectomy for uterine cervical cancer, the CAD system using the Bayesian classifier estimated the probability of metastasis based on MR findings and clinical findings. We compared the diagnostic accuracy for detecting metastatic LNs in the CAD and MR findings. RESULTS: Metastasis was diagnosed in 70 (12%) LNs from 34 (24%) patients. The area under ROC curves of CAD (0.924) was greater than those of the mean ADC (0.854), minimum ADC (0.849), maximum ADC (0.827), short-axis diameter (0.856) and long-axis diameter (0.753) (P < 0.05). The specificity and accuracy of the CAD (86%, 86%) were greater than those of the mean ADC (77%, 77%), maximum ADC (77%, 77%), minimum ADC (68%, 70%), and short-axis diameter (65%, 67%) (P < 0.05). CONCLUSION: CAD system can improve the diagnostic performance of MR for detecting metastatic LNs in uterine cervical cancer.

The serum CA-125 concentration data assists in evaluating CT imaging information when used to differentiate borderline ovarian tumor from malignant epithelial ovarian tumors.

OBJECTIVE: We wanted to evaluate the diagnostic value of serum CA-125 concentration, when used in combination with the preoperative contrast-enhanced CT results, to differentiate borderline ovarian tumors (BOTs) from stage I malignant epithelial ovarian tumors (MEOTs). MATERIALS AND METHODS: Ninety-eight masses (46 BOTs and 52 stage I MEOTs) from 87 consecutive patients (49 with BOTs and 38 with stage I MEOTs) who had undergone preoperative contrast-enhanced computed tomography (CT) and surgical staging were evaluated retrospectively and independently by two radiologists. The preoperative serum CA-125 concentration was measured in all patients. The utility of analyzing serum CA-125 concentration in combination with the CT results was evaluated by receiver operating characteristic (ROC) curve analysis. RESULTS: An irregular tumor surface and lymphadenopathy were predictive of a MEOT. ROC analysis showed that the combination of CT data and the serum CA-125 level resulted in a higher diagnostic performance than did using the CT alone for differentiating BOTs from MEOTs. The areas under the curves (AUCs) without and with the use of the serum CA-125 level data were 0.67 (95% confidence interval [CI]: 0.57-0.77) and 0.78 (95% CI: 0.68-0.85), respectively, for reader 1 (p = 0.029) and 0.71 (95% CI: 0.61-0.80) and 0.81 (95% CI: 0.72-0.89), respectively, for reader 2 (p = 0.009). CONCLUSION: The serum CA-125 concentration is of additional diagnostic value when used in conjunction with the CT imaging results for differentiating BOTs from MEOTs.

CT findings of mature cystic teratoma with malignant transformation: comparison with mature cystic teratoma.

PURPOSE: To evaluate the imaging findings of mature cystic teratoma with malignant transformation (malignant teratoma) compared with the corresponding mature cystic teratoma (benign teratoma). MATERIALS AND METHODS: This study enrolled 1325 patients with 12 malignant teratomas and 1313 benign teratomas. We compared the computed tomographic (CT) findings of eight malignant teratomas and 15 benign teratomas; both groups were matched in terms of tumor size (>9.9 cm) and patient age (>45 years). The CT images were retrospectively evaluated with focus on soft tissue components; size, border (regular or irregular), the presence or absence of nodular formation, enhancement, the angle formed between the soft tissue components and the inner wall of the cyst (acute or obtuse), and transmural growth as well as metastasis including lymphadenopathy and disseminated disease. Using the Fischer's Exact test, each evaluating parameter was compared between the two groups. RESULTS: Soft tissue components were observed in 75% (six of eight) of malignant teratomas and in 33% (five of fifteen) of benign teratomas; 100% (six of six) of soft component in malignant teratomas had a nodular formation and none of soft component in benign teratomas showed nodular formation; 83% (five of six) of soft component in malignant teratomas had enhancement as well as an obtuse angle between the soft tissue components and the inner wall of the cyst. None of soft component in benign teratomas showed enhancement and 20% (one of five) of soft component in benign teratomas had an obtuse angle; 33% (two of six) of soft component in malignant teratomas showed transmural growth, 13% (one of eight) of malignant teratoma showed lymphadenopathy, and 38% (three of eight) showed disseminated disease. None of benign teratomas showed transmural growth, lymphadenopathy, or disseminated disease. A statistically significant difference between patients with and without malignant transformation was seen in terms of nodular formation, obtuse angle, and enhancement of the soft tissue components (P<.05). CONCLUSION: Malignant teratoma is characterized by the following imaging findings: the presence of a nodular forming and enhancing soft tissue component, an obtuse angle between the soft tissue and the inner wall of the cyst, as well as extracapsular tumor growth with extension into adjacent structures or metastasis. Therefore, we can differentiate malignant teratoma from benign teratoma using CT findings.