Dae Chul Jung

Additional value of MR/PET fusion compared with PET/CT in the detection of lymph node metastases in cervical cancer patients

We evaluated the additional diagnostic value of magnetic resonance/positron emission tomography (MR/PET) fusion in the detection of metastatic lymph nodes in cervical cancer patients. Seventy nine patients with FIGO stage IB-IVA cervical cancer who had undergone both magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT) before lymphadenectomy were included in this study. Image analysis was first performed with PET/CT images only. A second analysis was then performed with MR/PET fused images that focused on the additional information obtained from the MR images. Lymphadenectomy involved removing all visible lymph nodes in the surgical field. To enable nodal group-specific comparisons, para-aortic and pelvic lymph nodes were divided into seven nodal groups: para-aortic, both common iliac, both external iliac and both internal iliac/obturator areas. Histopathological evaluation of lymph nodes has been the diagnostic standard. The value of the additional information from the MR images was evaluated by means of receiver operating characteristic (ROC) analysis. Fused MR/PET rendered readers to detect six more metastatic lymph node groups. The sensitivity and specificity of PET/CT and fused MR/PET were 44.1%, 93.9% and 54.2%, 92.7% respectively. The ROC analysis demonstrated a higher diagnostic performance of fused MR/PET compared to PET/CT alone for detecting lymph node metastases (p=0.0259). The findings of this study demonstrate the additional diagnostic value of fused MR/PET images compared with PET/CT in the detection of metastatic lymph nodes in patients with uterine cervical cancer.

Carbonic anhydrase IX (CA9) modulates tumor-associated cell migration and invasion.

Expression of carbonic anhydrase IX (CA9) was shown to be strongly involved in high incidences of metastasis and poor prognosis in various human tumors. In this study, we investigated the possible role for CA9 in tumor metastases in vitro, using a gene transfection tool in the human cervical carcinoma cell line C33A. Gene expression profiling of CA9-transfected cells (C33A/CA9) and vector-transfected cells (C33A/Mock) was investigated by DNA microarray. The biological functions of differentially expressed genes between the C33A/CA9 and C33A/Mock cells included cell growth, regulation of cell–cell and cell–extracellular matrix adhesion and cytoskeletal organization. Immunofluorescent stain and Matrigel culture showed cytoskeletal remodeling, disassembled focal adhesion, weakened cell-cell adhesion and increased motility in C33A/CA9 cells. These invasive and metastatic phenotypes were associated with Rho-GTPase-related epithelial-mesenchymal transition. Inhibition of the Rho/Rho kinase pathway by a ROCK inhibitor (Y27632) and si-Rho (short interference RNA against RhoA) showed that Rho-GTPase signaling was involved in cellular morphologic and migratory changes. The effect of CA9 on Rho-GTPase signaling was also confirmed by silencing CA9 expression. Our results suggest that CA9 overexpression induces weakening of cell adhesions and augmented cell motility by aberrant Rho-GTPase signal transduction. Our study shows an underlying mechanism of CA9-related enhanced metastatic potential of tumor cells.

Pretreatment assessment of tumor enhancement on contrast-enhanced computed tomography as a potential predictor of treatment outcome in metastatic renal cell carcinoma patients receiving antiangiogenic therapy.

Tumor vascularity is a potential predictor of treatment outcomes in metastatic renal cell carcinoma (mRCC), and contrast enhancement of tumors in computed tomography (CT) is correlated significantly with microvessel density. In this study, the authors investigated whether tumor enhancement in contrast‐enhanced CT (CECT) is useful for predicting outcomes in patients with mRCC who are receiving antiangiogenic therapy.

Prostate Cancer: PI-RADS Version 2 Helps Preoperatively Predict Clinically Significant Cancers

Purpose To retrospectively analyze whether Prostate Imaging Reporting and Data System (PI-RADS) version 2 is helpful for the detection of clinically significant prostate cancer. Materials and Methods Institutional review board approved this retrospective study. A total of 425 patients with prostate cancer who had undergone magnetic resonance (MR) imaging and radical prostatectomy were included. Preoperative parameters such as prostate-specific antigen, biopsy Gleason score, greatest percentage of the core, percentage of the positive core number, and score at PI-RADS version 2 with MR imaging were investigated. Two independent readers performed PI-RADS scoring. Clinically significant prostate cancer was defined as follows: (a) Gleason score of 7 or greater, (b) tumor volume of 0.5 cm(3) or greater, or a (c) positive extracapsular extension or seminal vesicle invasion. The reference standard was based on review of surgical specimen. Logistic regression was conducted to determine which parameters are associated with the presence of clinically significant cancer. Interreader agreement (ie, score ≥4 or not) was investigated by using κ statistics. Results At univariate analysis, all of the preoperative parameters were significant for clinically significant prostate cancer (P < .05). However, multivariate analysis revealed that PI-RADS score was the only significant parameter for both readers (reader 1: odds ratio = 28.170, P = .002; reader 2: odds ratio = 5.474, P = .007). The interreader agreement was excellent for PI-RADS score of 4 or greater (weighted κ = 0.801; 95% confidence interval: 0.737, 0.865). Conclusion The use of PI-RADS version 2 may help preoperatively diagnose clinically significant prostate cancer. (©) RSNA, 2016.

Preoperative prediction model of lymph node metastasis in endometrial cancer.

Background: We aimed to develop a preoperative prediction model identifying the low-risk group for lymph node metastasis in endometrial cancer. Methods: In 110 patients who underwent preoperative magnetic resonance imaging and serum CA-125 test, logistic analysis was performed to identify predictors. The coefficients obtained from logistic regression were used to construct a scoring system, and a receiver operator characteristic curve was created. Results: Lymph node metastases were found in 14 (12.7%) of 110 patients. After multivariate logistic regression analysis, histologic grade, preoperative CA-125 levels, disease extent, and myometrial invasion assessed by magnetic resonance imaging were selected as viable predictors. The scoring system was internally validated using bootstrapping (P < 0.001), and receiver operator characteristic curve yielded the area under the curve of 0.902. The patients with the score of 0 or 1 (57.3%) were identified as a low-risk group, and no nodal metastasis was observed among them (negative predictive value, 100%: 95% confidence interval, 94.3%-100%). Conclusion: The current study suggests that preoperative prediction system to identify the risk of lymph node metastasis is feasible. This model may be useful in preoperative counseling about cost and benefit of systemic lymph node dissection.

The validity of tumour diameter assessed by magnetic resonance imaging and gross specimen with regard to tumour volume in cervical cancer patients

We compared the tumour size measured by magnetic resonance imaging (MRI) with that of gross specimen regarding the virtual tumour volume. Eighty three patients with International Federation of Obstetrics and Gynecology (FIGO) stage Ib to IIa cervical cancer underwent MRI before radical hysterectomy. The largest tumour diameter was determined by both MRI and gross specimen measurement. Tumour volume was calculated by the standard technique of multiplying the sum of the areas by the slice thickness. Paired t-test was used to compare the MRI and gross specimen derived diameters. Pearson correlation coefficient was calculated to evaluate the relationship between the tumour size and volume. The mean diameters of the MRI and gross specimen derived tumour measurements were 3.0 cm (standard deviation, 0.9 cm) and 3.5 cm (standard deviation, 1.2 cm) (p<0.001), respectively. Mean MRI-based tumour volume was 12.5 cm(3) (standard deviation, 10.4 cm(3)). Tumour diameter measured by MRI had a significantly higher correlation with tumour volume measured by MRI (r(p)=0.734) compared with that measured on the gross specimen (r(p)=0.690; Steigers Z test, p=0.019). The tumour diameter measured by MRI was smaller than gross specimen measurement and correlated more closely with tumour volume in patients with cervical cancer. This study illustrates the value of MRI as a tool for tumour size measurement.

Multidetector CT predictors of incomplete resection in primary cytoreduction of patients with advanced ovarian cancer

This study was designed to develop a preoperative predictor model using multidetector CT (MDCT) imaging findings for the prediction of surgical outcome in patients with advanced epithelial ovarian cancer (EOC). Seventy-seven patients with advanced EOC who had preoperative MDCT and who had undergone primary cytoreductive surgery between January 1999 and June 2008 were enrolled in the study. All MDCT examinations were analysed retrospectively, assessing nine imaging features without knowledge of the operative findings. The complete debulking rate and optimal debulking rate were 42.5% and 93.2%, respectively. Based on the use of univariate and multivariate analysis, one imaging feature that showed the presence of upper abdominal ascites was significantly associated with incomplete tumour resection (P = 0.019 on univariate analysis, P = 0.04 on multivariate analysis). The combination of the MDCT findings that showed the presence of upper abdominal ascites and diffuse subdiaphragmatic peritoneal nodularity was associated with an incomplete resection of a tumour (P = 0.04; specificity 80.0%; positive predictive value 76.9%). It is important that emphasis on the upper abdominal sites of the tumour is helpful when reporting preoperative MDCT results.

Pre-operative prediction of advanced prostatic cancer using clinical decision support systems: accuracy comparison between support vector machine and artificial neural network.

Objective The purpose of the current study was to develop support vector machine (SVM) and artificial neural network (ANN) models for the pre-operative prediction of advanced prostate cancer by using the parameters acquired from transrectal ultrasound (TRUS)-guided prostate biopsies, and to compare the accuracies between the two models. Materials and Methods Five hundred thirty-two consecutive patients who underwent prostate biopsies and prostatectomies for prostate cancer were divided into the training and test groups (n = 300 versus n = 232). From the data in the training group, two clinical decision support systems (CDSSs-[SVM and ANN]) were constructed with input (age, prostate specific antigen level, digital rectal examination, and five biopsy parameters) and output data (the probability for advanced prostate cancer [> pT3a]). From the data of the test group, the accuracy of output data was evaluated. The areas under the receiver operating characteristic (ROC) curve (AUC) were calculated to summarize the overall performances, and a comparison of the ROC curves was performed (p < 0.05). Results The AUC of SVM and ANN is 0.805 and 0.719, respectively (p = 0.020), in the pre-operative prediction of advanced prostate cancer. Conclusion The performance of SVM is superior to ANN in the pre-operative prediction of advanced prostate cancer.

Imaging findings of primitive neuroectodermal tumors of the kidney.

Purpose: This study was designed to present the radiological imaging findings of a renal primitive neuroectodermal tumor (PNET). Materials and Methods: The study included 10 patients with pathologically proven renal PNETs. We assessed the size, margin, internal architecture, enhancement pattern, vein thrombosis, and presence of a metastasis of the tumors on multidetector-row computed tomography and magnetic resonance imaging. Results: The mean age of the patients was 31 years. Patients were predominantly male (males-females, 8:2). The mean diameter of a renal PNET was 12.7 cm. All masses were well defined with a lobulated contour. Necrosis and hemorrhage were detected in 9 cases, respectively. All of the masses showed weak heterogeneous enhancement with multiple irregular septumlike structures. Eight of the masses had renal vein thrombosis, and 4 masses had extension into inferior vena cava. A lymph node metastasis was detected in 3 patients. A lung metastasis was detected in 4 patients, and 2 of the patients also had a bone metastasis. Conclusions: A renal PNET usually appears as a weakly enhanced large mass with multiple septumlike structures, peripheral hemorrhage, venous thrombosis, and accompanied with a distant metastasis in a young adult.

Acoustic Radiation Force Impulse Measurement in Renal Transplantation: A Prospective, Longitudinal Study With Protocol Biopsies.

AbstractInterstitial fibrosis and tubular atrophy (IF/TA) is a common cause of kidney allograft loss. Several noninvasive techniques developed to assess tissue fibrosis are widely used to examine the liver. However, relatively few studies have investigated the use of elastographic methods to assess transplanted kidneys. The aim of this study was to explore the clinical implications of the acoustic radiation force impulse (ARFI) technique in renal transplant patients.A total of 91 patients who underwent living donor renal transplantation between September 2010 and January 2013 were included in this prospective study. Shear wave velocity (SWV) was measured by ARFI at baseline and predetermined time points (1 week and 6 and 12 months after transplantation). Protocol biopsies were performed at 12 months.Instead of reflecting IF/TA, SWVs were found to be related to time elapsed after transplantation. Mean SWV increased continuously during the first postoperative year (P < 0.001). In addition, mixed model analysis showed no correlation existed between SWV and serum creatinine (r = −0.2426, P = 0.0771). There was also no evidence of a relationship between IF/TA and serum creatinine (odds ratio [OR] = 1.220, P = 0.7648). Furthermore, SWV temporal patterns were dependent on the kidney weight to body weight ratio (KW/BW). In patients with a KW/BW <3.5 g/kg, mean SWV continuously increased for 12 months, whereas it decreased after 6 months in those with a KW/BW ≥3.5 g/kg.No significant correlation was observed between SWV and IF/TA or renal dysfunction. However, SWV was found to be related to the time after transplantation. Renal hemodynamics influenced by KW/BW might impact SWV values.