Kyunghwa Han

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.

MR Enterography for the Evaluation of Small-Bowel Inflammation in Crohn Disease by Using Diffusion-weighted Imaging without Intravenous Contrast Material: A Prospective Noninferiority Study

PURPOSE To determine whether magnetic resonance (MR) enterography performed with diffusion-weighted imaging (DWI) without intravenous contrast material is noninferior to contrast material-enhanced (CE) MR enterography for the evaluation of small-bowel inflammation in Crohn disease. MATERIALS AND METHODS Institutional review board approval and informed consent were obtained for this prospective noninferiority study. Fifty consecutive adults suspected of having Crohn disease underwent clinical assessment, MR enterography, and ileocolonoscopy within 1 week. MR enterography included conventional imaging and DWI (b = 900 sec/mm(2)). In 44 patients with Crohn disease, 171 small-bowel segments that were generally well distended and showed a wide range of findings, from normalcy to severe inflammation (34 men, 10 women; mean age ± standard deviation, 26.9 years ± 6.1), were selected for analysis. Image sets consisting of (a) T2-weighted sequences with DWI and (b) T2-weighted sequences with CE T1-weighted sequences were reviewed by using a crossover design with blinding and randomization. Statistical analyses included noninferiority testing regarding proportional agreement between DWI and CE MR enterography for the identification of bowel inflammation with a noninferiority margin of 80%, correlation between DWI and CE MR enterography scores of bowel inflammation severity, and comparison of accuracy between DWI and CE MR enterography for the diagnosis of terminal ileal inflammation by using endoscopic findings as the reference standard. RESULTS The agreement between DWI and CE MR enterography for the identification of bowel inflammation was 91.8% (157 of 171 segments; one-sided 95% confidence interval: ≥88.4%). The correlation coefficient between DWI and CE MR enterography scores was 0.937 (P < .001). DWI and CE MR enterography did not differ significantly regarding the sensitivity and specificity for the diagnosis of terminal ileal inflammation (P > .999). DWI and CE MR enterography concurred in the diagnosis of penetrating complications in five of eight segments. CONCLUSION DWI MR enterography was noninferior to CE MR enterography for the evaluation of inflammation in Crohn disease in generally well-distended small bowel, except for the diagnosis of penetration.

Shear wave elastography of thyroid nodules for the prediction of malignancy in a large scale study

OBJECTIVES The purpose of this study is to validate the usefulness of shear wave elastography (SWE) in predicting thyroid malignancy with a large-scale quantitative SWE data. METHODS This restrospective study included 476 thyroid nodules in 453 patients who underwent gray-scale US and SWE before US-guided fine-needle aspiration biopsy (US-FNA) or surgical excision were included. Gray-scale findings and SWE elasticity indices (EIs) were retrospectively reviewed and compared between benign and malignant thyroid nodules. The optimal cut-off values of EIs for predicting malignancy were determined. The diagnostic performances of gray-scale US and SWE for predicting malignancy were analyzed. The diagnostic performance was compared between the gray-scale US findings only and the combined use of gray-scale US findings with SWEs. RESULTS All EIs of malignant thyroid nodules were significantly higher than those of benign nodules (p≤.001). The optimal cut-off value of each EI for predicting malignancy was 85.2kPa of Emean, 94.0kPa of Emax, 54.0kPa of Emin. Emean (OR 3.071, p=.005) and Emax (OR 3.015, p=.003) were the independent predictors of thyroid malignancy. Combined use of gray-scale US findings and each EI showed elevated sensitivity (95.0-95.5% vs 92.9%, p≤.005) and AUC (0.820-0.834 vs 0.769, p≤.005) for predicting malignancy, compared with the use of only gray-scale US findings. CONCLUSIONS Quantitative parameters of SWE were the independent predictors of thyroid malignancy and SWE evaluation combined with gray-scale US was adjunctive to the diagnostic performance of gray-scale US for predicting thyroid malignancy.

Itraconazole-induced acute hepatitis

Siu, In October 1991, a 4(i-year-old Cauca.sian woman took norfloxacin 400 mg twice daily for 7 days, lor a urinary tract infection. As she completed the course of treatment she noticed an itchy rash on her back and abdomen. The rash consisted of profuse, clustered vesicles on an inflanimiitory base, predominantly localized to the lower back, infraniammary areas and abdomen. There were no bucca! iesion,s. Two weeks after its onset the eruption changed in character and became pustular. Histopathology showed intraepidermal bullae with acantholysis. and a mixed perivascular infiltrate of lymphocytes, histiocytes and neutrophils (Fig, 1), Both direct and indirect immunofluorescence (the latter was performed on two occasions) were negative for all immunoreactants.

Comparative Effectiveness and Safety of Preoperative Lung Localization for Pulmonary Nodules: A Systematic Review and Meta-analysis

Background: An optimal method of preoperative localization for pulmonary nodules has yet to be established. This systematic review and meta‐analysis aimed to compare the success and complication rates associated with three pulmonary nodule localization methods for video‐assisted thoracoscopic surgery (VATS): hook‐wire localization, microcoil localization, and lipiodol localization. Methods: We searched the PubMed, MEDLINE, and EMBASE databases for prospective or retrospective English language studies of VATS localization in adult patients. A noncomparative, random effects model–based meta‐analysis was performed to obtain pooled success and complication rates for the three localization methods. Results: A total of 46 clinical studies were enrolled, including 30, 9, and 7 studies of hook‐wire, microcoil, and lipiodol localization, respectively. The successful targeting rates for hook‐wire, microcoil, and lipiodol localization were 0.98 (95% CI, 0.97–0.99), 0.98 (95% CI, 0.96–0.99), and 0.99 (95% CI, 0.98–1.00), respectively, with corresponding successful operative field targeting rates of 0.94 (95% CI, 0.91–0.96), 0.97 (95% CI, 0.95–0.98), and 0.99 (95% CI, 0.98–1.00), respectively. In addition, the successful VATS rates with hook‐wire, microcoil, and lipiodol localization were 0.96 (95% CI, 0.94–0.97), 0.97 (95% CI, 0.94–0.99), and 0.99 (95% CI, 0.98–1.00), respectively. Regarding complications, hook‐wire, microcoil, and lipiodol localization were associated with pneumothorax rates of 0.35 (95% CI, 0.28–0.43), 0.16 (95% CI, 0.07–0.34), and 0.31 (95% CI, 0.20–0.46), respectively and hemorrhage rates of 0.16 (95% CI, 0.11–0.23), 0.06 (95% CI, 0.03–0.11), and 0.12 (95% CI, 0.05–0.23), respectively. Conclusions: All three localization methods yielded similarly highly successful targeting rates. However, hook‐wire localization had a relatively lower successful operative field targeting rate because of dislodgement or migration. Lipiodol localization had the highest overall success rate, and microcoil localization yielded the lowest complication rates.

Standardized uptake value of 18F-fluorodeoxyglucose positron emission tomography for prediction of tumor recurrence in breast cancer beyond tumor burden

Introduction18F-fluorodeoxyglucose positron emission tomography (FDG-PET) can reveal the metabolic activity of malignant tumors. Recent advances gained from molecular studies suggest that tumor biology can be a good predictor of prognosis in breast cancer. We compared the ability of maximum standardized uptake values (SUVmax) derived by FDG-PET with tumor burden in predicting tumor recurrence for patients with breast cancer.Methods496 patients with breast cancer who underwent preoperative FDG-PET between April 2004 and May 2009 were retrospectively identified. SUVmax was obtained by FDG-PET, and the cutoff point was defined using a time-dependent receiver operating characteristic curve for recurrence-free survival (RFS). The primary endpoint was RFS.ResultsIn multivariate analysis for RFS, SUVmax carried independent prognostic significance (hazard ratio, 2.39; 95% confidence interval, 1.20 to 4.76; P = 0.012). When the patients were classified into four groups according to the combined factors of tumor size (≤2 cm versus >2 cm) and SUVmax (<4 versus ≥4), RFS differed significantly (P < 0.001). Similarly, SUVmax had prognostic value in combination with nodal status (negative versus positive) or stage (I versus II and III) (P < 0.001 and P = 0.001, respectively). In hormone receptor–positive disease, SUVmax remained a significant prognostic factor for RFS based on multivariate analysis.ConclusionsOur results highlight the prognostic value of FDG-PET in prediction of tumor relapse for patients with breast cancer. Particularly in patients with hormone receptor–positive disease, the tumor metabolic information provided by FDG-PET is more significantly correlated with prognosis than tumor burden.

Diagnosis and Management of Small Thyroid Nodules: A Comparative Study with Six Guidelines for Thyroid Nodules

Purpose To investigate the diagnostic performances of six guidelines used to assess thyroid nodules and to determine whether any of these guidelines identify cancers of aggressive form in this population. Materials and Methods From March 2007 to February 2010, 4696 thyroid nodules that were 1-2 cm in 4585 patients were diagnosed as benign or malignant on the basis of cytopathologic results. Ultrasonographic examinations of the thyroid nodules were retrospectively reviewed and categorized according to the categories defined by six previously published guidelines for thyroid nodules. Diagnostic performances of each guideline for diagnosing thyroid cancer were calculated and compared by using the generalized estimating equation method for logistic regression. Multivariate regression analysis was used to analyze predictors for distant metastasis and recurrence and persistence in patients with small thyroid cancer. Results Of the 4696 thyroid nodules, 3652 (77.8%) were benign and 1044 (22.2%) were malignant. Followed were 873 patients who were diagnosed with small thyroid cancer, of whom 12 had distant metastasis and 66 had recurrence or persistence of disease. Specificity, positive predictive value, and accuracy were highest with criteria developed by Kim et al (83.1%, 59.6%, and 84.0%, respectively), while sensitivity and negative predictive value were highest with Thyroid Imaging Reporting and Data System developed by Kwak et al (98.8% and 98.6%, respectively; P < .001). Positive findings that indicated fine-needle aspiration in the guidelines did not show significant association with distant metastasis or recurrence or persistence (P > .05), but the study power was low to detect a difference. Conclusion With its high specificity and accuracy, criteria from Kim et al may be an effective guideline to use in the management of small thyroid nodules.

Diffusion-Weighted MR Enterography to Monitor Bowel Inflammation after Medical Therapy in Crohn's Disease: A Prospective Longitudinal Study

Objective To prospectively evaluate the performance of diffusion-weighted imaging (DWI) to monitor bowel inflammation after medical therapy for Crohns disease (CD). Materials and Methods Before and following 1–2 years of medical therapy, between October 2012 and May 2015, 18 randomly selected adult CD patients (male:female, 13:5; mean age ± SD, 25.8 ± 7.9 years at the time of enrollment) prospectively underwent MR enterography (MRE) including DWI (b = 900 s/mm2) and ileocolonoscopy. Thirty-seven prospectively defined index lesions (one contiguous endoscopy-confirmed inflamed area chosen from each inflamed anatomical bowel segment; 1–4 index lesions per patient; median, 2 lesions) were assessed on pre- and post-treatment MRE and endoscopy. Visual assessment of treatment responses on DWI in 4 categories including complete remission and reduced, unchanged or increased inflammation, and measurements of changes in apparent diffusion coefficient (ΔADC), i.e., pre-treatment–post-treatment, were performed by 2 independent readers. Endoscopic findings and CD MRI activity index (CDMI) obtained using conventional MRE served as reference standards. Results ΔADC significantly differed between improved (i.e., complete remission and reduced inflammation) and unimproved (i.e., unchanged or increased inflammation) lesions: mean ± SD (× 10-3 mm2/s) of -0.65 ± 0.58 vs. 0.06 ± 0.15 for reader 1 (p = 0.022) and -0.68 ± 0.56 vs. 0.10 ± 0.26 for reader 2 (p = 0.025). DWI accuracy for diagnosing complete remission or improved inflammation ranged from 76% (28/37) to 84% (31/37). A significant negative correlation was noted between ΔADC and ΔCDMI for both readers with correlation coefficients of -0.438 and -0.461, respectively (p < 0.05). Conclusion DWI is potentially a feasible tool to monitor quantitatively and qualitatively bowel inflammation of CD after medical treatment.

Gadolinium deposition in the brain: association with various GBCAs using a generalized additive model

AbstractObjectivesTo determine the relationship between the number of administrations of various gadolinium-based contrast agents (GBCAs) and increased T1 signal intensity in the globus pallidus (GP) and dentate nucleus (DN).MethodsThis retrospective study included 122 patients who underwent double-dose GBCA-enhanced magnetic resonance imaging. Two radiologists calculated GP-to-thalamus (TH) signal intensity ratio, DN-to-pons signal intensity ratio and relative change (Rchange) between the baseline and final examinations. Interobserver agreement was evaluated. The relationships between Rchange and several factors, including number of each GBCA administrations, were analysed using a generalized additive model.ResultsSix patients (4.9%) received linear GBCAs (mean 20.8 number of administration; range 15–30), 44 patients (36.1%) received macrocyclic GBCAs (mean 26.1; range 14–51) and 72 patients (59.0%) received both types of GBCAs (mean 31.5; range 12–65). Interobserver agreement was almost perfect (0.99; 95% CI: 0.99–0.99). Rchange (DN:pons) was associated with gadodiamide (p = 0.006) and gadopentetate dimeglumine (p < 0.001), but not with other GBCAs. Rchange (GP:TH) was not associated with GBCA administration.ConclusionsPrevious administration of linear agents gadoiamide and gadopentetate dimeglumine is associated with increased T1 signal intensity in the DN, whereas macrocyclic GBCAs do not show an association.Key points• Certain linear GBCAs are associated with T1 signal change in the dentate nucleus. • The signal change is related to the administration number of certain linear GBCAs. • Difference in signal change may reflect differences in stability of agents.

How to Develop, Validate, and Compare Clinical Prediction Models Involving Radiological Parameters: Study Design and Statistical Methods

Clinical prediction models are developed to calculate estimates of the probability of the presence/occurrence or future course of a particular prognostic or diagnostic outcome from multiple clinical or non-clinical parameters. Radiologic imaging techniques are being developed for accurate detection and early diagnosis of disease, which will eventually affect patient outcomes. Hence, results obtained by radiological means, especially diagnostic imaging, are frequently incorporated into a clinical prediction model as important predictive parameters, and the performance of the prediction model may improve in both diagnostic and prognostic settings. This article explains in a conceptual manner the overall process of developing and validating a clinical prediction model involving radiological parameters in relation to the study design and statistical methods. Collection of a raw dataset; selection of an appropriate statistical model; predictor selection; evaluation of model performance using a calibration plot, Hosmer-Lemeshow test and c-index; internal and external validation; comparison of different models using c-index, net reclassification improvement, and integrated discrimination improvement; and a method to create an easy-to-use prediction score system will be addressed. This article may serve as a practical methodological reference for clinical researchers.