Malignant Focal Lesions Research Articles

The Role of CT Perfusion in Differentiating Benign Versus Malignant Focal Pulmonary Lesions.

Contrast-enhanced CT scan is the standard imaging for the characterization and evaluation of focal parenchymal lung lesions. It relies on morphology and enhancement patterns for the characterization of lung lesions. However, there is significant overlap among imaging features of various malignant and benign lesions. Hence, it is often necessary to obtain tissue diagnosis with invasive percutaneous or endoscopic-guided tissue sampling. It is often desirable to have non-invasive techniques that can differentiate malignant and benign lung lesions. CT perfusion is an emerging CT technology that allows functional assessment of tissue vascularity through various parameters and can help in differentiating benign and malignant focal lung lesions. The purpose of this study was to assess the role of the CT perfusion technique in differentiating malignant and benign focal parenchymal lung lesions. In this prospective observational study, CT perfusion was performed on 41 patients with focal parenchymal lung lesions from December 2020 to June 2022. The four-dimensional range was planned to cover the entire craniocaudal extent of the lesion, followed by a volume perfusion CT (VPCT) of the lesion. A total of 27 dynamic datasets were acquired with a scan interval of 1.5 seconds and a total scan time of 42 seconds. CT perfusion parameters of blood flow (BF), blood volume (BV), and k-trans of the lesionwere measured withmathematical algorithms available in the Syngo.via CT perfusion software (Siemens Healthcare, Erlangen, Germany). The median BV in benign lesions was found to be 5.5 mL/100 g, with an interquartile range of 3.3-6.9 and a p-value < 0.001. The median BV in malignant lesions was found to be 11.35 mL/100 g, with an interquartile range of 9.57-13.21 and a p-value ≤ 0.001. The median BF for benign lesions was 45.5 mL/100 g/min, with an interquartile range of 33.8-48.5and a p-value ≤ 0.001. The median BF for malignant lesion was 61.77 mL/100 g/min, with an interquartile range of 33.8-48.5and a p-value ≤ 0.001. The median k-trans in the case of benign lesions was found to be 4.2 mL/100 g/min, with an interquartile range of 3.13-6.8 and a p-value ≤ 0.001. The median k-trans in the case of the malignant lesion was found to be 12.05 mL/100g/min, with an interquartile range of 7.20-33.42 and a p-value < 0.001. Our study has also shown BV to have an accuracy of 92.68%, sensitivity of 93.3%, and specificity of 90.01%. Our study has shown that CT perfusion values of BV, BF, and k-trans can be used to differentiate between benign and malignant focal lung parenchymal lesions. K-trans is the most sensitive parameter while BV and BF have greater accuracy and specificity.

Diagnostic value of pseudocapsule ring hyperenhancement in contrast-enhanced ultrasound in renal focal lesions.

To investigate the diagnostic value of pseudocapsule ring hyperenhancement in contrast-enhanced ultrasound (CEUS) of focal renal lesions. Ninety eligible patients admitted were selected as the study subjects. The incidence rate of annular hyperenhancement in different benign and malignant focal lesions during angiography and the shape of annular enhancement were counted. The correlation between the occurrence of benign and malignant renal tumors and annular hyperenhancement and unenhanced areas was also analyzed. Capsule enhancement was observed in 56 cases, including 50 cases of malignant tumors (89.3%, 50/56) and 6 cases of benign tumors (10.7%, 6/56). Pearson correlation analysis showed that renal malignancy was positively associated with the occurrence of pseudocapsule ring hyperenhancement (γ = 0.489, P < 0.001). Benign and malignant renal tumors were positively correlated with the occurrence of non-enhancing areas (γ = 0.215, P = 0.042). The thickness and peak intensity of pseudocapsule ring enhancement in renal malignant tumors were significantly higher than those in benign tumors (all P < 0.001), while the time to peak was significantly lower than that in benign tumors (P < 0.001). The results of receiver operating characteristic (ROC) curve showed that the ring enhancement thickness, time to peak, and area under ROC curve of peak intensity of tumor reached more than 0.9. In CEUS, the pseudocapsule of focal renal lesions is a characteristic feature of renal malignant tumors, which can be used as a differential basis for benign and malignant tumors to improve the accuracy of benign and malignant renal tumors.

Evaluating breast ultrasound S-detect image analysis for small focal breast lesions.

S-Detect is a computer-assisted, artificial intelligence-based system of image analysis that has been integrated into the software of ultrasound (US) equipment and has the capacity to independently differentiate between benign and malignant focal breast lesions. Since the revision and upgrade in both the breast imaging-reporting and data system (BI-RADS) US lexicon and the S-Detect software in 2013, evidence that supports improved accuracy and specificity of radiologists' assessment of breast lesions has accumulated. However, such assessment using S-Detect technology to distinguish malignant from breast lesions with a diameter no greater than 2cm requires further investigation. The US images of focal breast lesions from 295 patients in our hospital from January 2019 to June 2022 were collected. The BI-RADS data were evaluated by the embedded program and as manually modified prior to the determination of a pathological diagnosis. The receiver operator characteristic (ROC) curves were constructed to compare the diagnostic accuracy between the assessments of the conventional US images, the S-Detect classification, and the combination of the two. There were 326 lesions identified in 295 patients, of which pathological confirmation demonstrated that 239 were benign and 87 were malignant. The sensitivity, specificity, and accuracy of the conventional imaging group were 75.86%, 93.31%, and 88.65%. The sensitivity, specificity, and accuracy of the S-Detect classification group were 87.36%, 88.28%, and 88.04%, respectively. The assessment of the amended combination of S-Detect with US image analysis (Co-Detect group) was improved with a sensitivity, specificity, and accuracy of 90.80%, 94.56%, and 93.56%, respectively. The diagnostic accuracy of the conventional US group, the S-Detect group, and the Co-Detect group using area under curves was 0.85, 0.88 and 0.93, respectively. The Co-Detect group had a better diagnostic efficiency compared with the conventional US group (Z = 3.882, p = 0.0001) and the S-Detect group (Z = 3.861, p = 0.0001). There was no significant difference in distinguishing benign from malignant small breast lesions when comparing conventional US and S-Detect techniques. The addition of S-Detect technology to conventional US imaging provided a novel and feasible method to differentiate benign from malignant small breast nodules.

Diagnostic performance of 2D-shear wave elastography in the diagnosis of breast cancer: a clinical appraisal of cutoff values.

To assess the role of 2D-shear wave elastography (2D-SWE) in differentiating benign from malignant focal breast lesions (FBLs), providing new vendor-specific cutoff values. 158 FBLs (size: 3.5-50mm) detected in 151 women (age: 21-87years) were prospectively evaluated by means 2D-SWE. For each lesion, an expert radiologist assessed US BI-RADS category and calculated the following four 2D-SWE parameters: (1) elasticity maximum (Emax); (2) mean elasticity (Emean); (3) minimum elasticity (Emin); (4) elasticity ratio (Eratio). US-guided core-biopsy was considered as standard of reference for all the FBLs classified as BI-RADS 4 or 5. For each 2D-SWE parameter, the optimal cutoff value for a diagnostic test was calculated using the Youden method. Diagnostic performance of the US BI-RADS and 2D-SWE parameters was calculated accordingly. 83/158 (52.5%) FBLs were benign and 75/158 (47.5%) were malignant. Statistically significant higher stiffness values were observed in malignant FBLs for all 2D-SWE parameters than in benign ones (p < 0.001). 2D-SWE cutoff values were 82.6kPa, 66.0kPa and 53.6kPa, respectively, for Emax, Emean, Emin and 330.8% for Eratio. The 2D-SWE parameter showing the best diagnostic accuracy was Emax (85.44%). Considering US BI-RADS 3 (n = 60) and 4a (n = 32) FBLs, Emax and Emean showed the best diagnostic accuracy (85.87% for both), without a statistically significant decrease in sensitivity (p = 0.7003 and p = 1, respectively). Our study provides new vendor-specific cutoff values for 2D-SWE, suggesting its possible clinical use in the adjunctive assessment of category US-BI-RADS 3 and 4a breast masses.

Role of diffusion weighted MRI imaging in characterization of hepatic focal lesions in cirrhotic patients in comparison to dynamic cross sectional imaging

Abstract Aim of work The aim of the study is to show the feasibility of diffusion weighted (DWI) MRI with calculation of the apparent diffusion coefficient in characterization of hepatic focal lesions as well as differentiating benign from malignant lesions in cirrhotic patients. Patients and Methods The study included 35 patients (25 males and 10 females) by cross sectional study and convenient sampling at the Demerdash hospital, inclusion criteria: patients diagnosed by hepatic focal lesions on top of post-viral induced cirrhosis, detected by ultrasound, triphasic CT or dynamic MRI imaging. All patients to be included in the study underwent characterization of hepatic focal lesions to differentiate benign from malignant lesions using a combination of characteristic imaging criteria, including contrast enhancement patterns on MRI. Sequences used were T2 weighted imaging, T2 Spectral Attenuated Inversion Recovery (SPAIR), and diffusion weighted imaging sequences with estimation of the ADC map and calculation of the ADC values. Results Our study was carried on a total of 35 patients including 25 males and 10 female patients having a mean age of 59 ± 10.2 years (58.1 ± 11 and 61.2 ± 8 years for the male and female patients respectively). DWI and ADC showed statistically significant difference among the benign and malignant focal lesions in terms of their diffusion restriction criteria ( P &amp;lt; 0.0001), with a sensitivity, specificity, positive and negative predictive values of 100% (95% CI = 89.5 – 100%), 92.3% (95% CI = 79.6 – 97.3%), 91.6% (95% CI = 78.1 – 97.1%) and 100% (95% CI = 90.3 – 100%), as well as a likelihood ratio of 13. On comparing the ADC values of the focal lesions for the benign and malignant focal lesions, the malignant lesions showed statistically significant lower means as compared to the benign lesions (malignant = 1.08 ± 0.28 x 10-3 mm2/s, benign =2.0 ± 0 x 10-3 mm2/s, P &amp;lt; 0.0001). ROC curve analysis of the ADC values of the benign and malignant focal lesions was highly significant (P &amp;lt; 0.0001), with an area under curve of 0.9745 (97.45% overall accuracy), giving an ADC cut-off value of (&amp;lt; 0.98 x 10-3 mm2/s) for malignant lesions with 97.2% sensitivity (95% CI = 85.83% - 99.86%), 97.2% specificity (95% CI = 85.83% - 99.86%) and a likelihood ratio of 35. Summary and conclusion DWI MRI and the calculation of the ADC are great non invasive possible tools to detect and characterize hepatic focal lesions as well as to differentiate benign from malignant lesions in cirrhotic patients especially in patients with renal impairment and allergy to contrast media also to avoid unnecessary biopsies.

The value of the added diffusion-weighted images to multiparametric MRI in the early diagnosis of uterine cervix cancers and nodal assessment

BackgroundCervical cancer still one of the most common causes of tumor-related death in developing countries presented in younger women. In this study, we aimed to evaluate the value of diffusion-weighted MRI in early diagnosis of malignant cervical lesions, to assess metastatic adenopathy, peritoneal dissemination, and possible tumor recurrence, and determine treatment response. This study included 60 patients with abnormal vaginal bleeding and suspected cervical lesion by US. A histopathological biopsy was done. Pelvic MR with DWI and dynamic contrast-enhanced MRI were done for all patients.ResultsAccording to the histopathological findings, we divided our studied 60 patents into two groups: group I, malignant lesions (46 lesions; 76.7%), and group II, benign lesions (14 lesions; 23.3%). Multiparametric MRI could detect all cervical lesions but with poor pathologic characterization, achieving 72.37% sensitivity, 37.50% specificity, 63.33% accuracy, 76.19% PPV, and 33.33% NPV. When compared with DWI with ADC value measurements at high b value (b = 800) to MRI exam, it showed a higher diagnostic accuracy with good lesion pathological characterization that achieved 95.65% sensitivity, 71.43% specificity, 90% accuracy, 91.67 PPV, and 83.33% NPV. The mean ADC value for malignant lesions was 0.86–1.1, mean = 0.92 ± 0.71 × 10−3 mm2/s, while the mean ADC value in the benign lesion group was 1.18 ± 0.1 × 10–3 mm2/s.ConclusionComparing DWI with ADC values measurements at high b value to the multiparametric MRI examination of the female pelvis increases the sensitivity, specificity, and diagnostic accuracy of characterization and early diagnosis of cervical malignant focal lesions and reduces the need for intravenous contrast administration.

Role of shear wave sono-elastography (SWE) in characterization of hepatic focal lesions

BackgroundFocal liver lesions are considered a major problem during abdominal examinations. Shear wave sono-elastography (SWE) has been demonstrated to be helpful in assessment of liver fibrosis degree.The purpose of this study was to evaluate the role of SWE in characterization of benign and malignant hepatic focal lesions.ResultsSeventy-five (75) patients with variable focal liver lesions (52 malignant and 23 benign) were analyzed by SWE. The stiffness values of surrounding hepatic parenchyma were also measured as a reference for readings of the focal lesion stiffness values. Final diagnosis was achieved by core needle biopsy (in 1 benign and 38 malignant cases) and contrast enhanced CT and MRI (in all cases).Cholangiocarcinoma (CCC) was the stiffest malignant lesion with median stiffness value (35.9 kPa). Focal nodular hyperplasia (FNH) was the stiffest benign lesion (26.7 kPa).The median stiffness value of malignant focal lesions (20.22 kPa) was significantly higher than that of benign focal lesions (10.68 kPa) (P value < 0.001).ROC curve of SWE median stiffness values for differentiation of benign from malignant hepatic focal lesions had AUC = 0.834, and using cut of value 14.165 kPa, yielding 98.1% sensitivity, 78.3% specificity, and 92% accuracy.ConclusionSWE has high accuracy in differentiating benign form malignant liver focal lesions with promising results in individual characterization of some malignant (HCC and CCC) and benign hepatic focal lesion (FNH from other benign lesions).

Does MRI diffusion help in the detection and characterization of benign and malignant hepatic focal lesions in the nonpediatric age group?

Introduction Liver MRI has been used in cases where ultrasound or computed tomography findings are equivocal. Diffusion-weighted imaging (DWI) established an important role in clinical use in the liver. DWI can potentially add useful information to conventional imaging. Objective The aim was to assess the role of DWI in the detection and characterization of hepatic focal lesions and its value to differentiate benign from malignant masses. Patients and methods The study included 40 patients, 19 women and 21 men, their ages ranged from 20 to 63 years. All patients underwent detailed MRI study of the abdomen. Diffusion study was performed with tridirectional diffusion gradients using b values 0, 500, and 1000 s/mm2 to increase the sensitivity. Apparent diffusion coefficient (ADC) maps and values were calculated for all lesions. Results In all, 20 patients were diagnosed to have benign lesions and 20 patients were diagnosed to have malignant lesions. Hemangiomas and cysts showed facilitated diffusion while adenomas show restricted diffusion pattern mimicking malignant focal lesions. On the other hand, all malignant lesions showed restricted diffusion evidenced by increased signal on increasing the b values and low signal on ADC maps. Mostly benign lesions show higher ADC values than malignant lesions. Conclusion Diffusion-weighted MRI sequence with quantitative ADC measurements should be used as an additional sequence to supplement conventional MRI protocol studies for proper characterization of focal hepatic lesions putting into consideration an overlap range.

Proton MR spectroscopy in characterization of focal bone lesions of peripheral skeleton

BackgroundThe aim of our study was to determine the value of single-voxel proton MR spectroscopy (1HMRS) in distinguishing benign from malignant focal bone lesions in the peripheral skeleton. MRI and 1HMRS was performed in 50 focal lesions (> 1 cm size) detected on radiographs of peripheral skeleton.1HMRS was performed at 1.5 T with TE of 144 ms with automatic shimming and water suppression. Qualitative analysis for a discrete choline peak at 3.2 ppm was done. Significance of the presence of choline peak on 1HMRS in distinguishing benign from malignant lesions was calculated using histopathology as a gold standard. Chi-square test was used and p value < 0.05 was considered significant.ResultsForty-one benign and 9 malignant lesions were confirmed by histopathological results. Amongst malignant lesions, choline peak was positive in all but 1 case of low-grade lymphoma. MR spectra of 11 benign lesions showed the presence of choline peak. All 7 benign giant cell tumors (GCT) were positive for choline peak. The sensitivity, specificity, PPV, NPV of proton MR spectroscopy in differentiating benign from malignant lesions were 87.5%,71%,38.8%, and 96.4% respectively. p value was significant (< 0.05).Conclusion1HMRS in focal bone lesions can help in the differentiation of malignant from benign musculoskeletal tumors. Although some benign lesions may show false-positive result, absence of choline peak is a reliable reassurance against malignancy. GCT is an exception amongst benign bone tumors as it consistently shows the presence of choline peak on 1HMRS.

Elastography of focal testicular lesions: current concepts and utility.

As a relatively new sonographic technique, tissue elastography has emerged as a qualitative and potentially quantitative adjunctive tool to provide additional information on tissue stiffness, aiming to further improve diagnostic confidence in discriminating benign from malignant focal testicular lesions. The purpose of this review is to provide an overview of the elastography techniques used to assess focal testicular lesions and their typical appearance on tissue elastography.

Clinical value of multi-slice spiral CT angiography in the diagnosis of abdominal tumors

Objective To study the clinical value of multi-slice spiral CT angiography in the diagnosis of abdominal tumors. Methods From January 2015 to December 2017, 90 patients with abdominal neoplasms in the First People's Hospital of Yongkang were divided into two groups according to double-blind randomized method, with 45 patients in each group.The patients with conventional CT scan were included in the control group, and the patients with multislice spiral CT angiography were selected as the observation group.The scan results, invasion range and location of abdominal tumor, vascular display and perfusion parameters were compared between the two groups. Results The diagnostic accuracy of abdominal tumor and invasion range in the observation group(93.33%, 80.00%) was higher than those of the control group(χ2=5.414, 5.086, all P<0.05). The proportions of abnormal thickening of one supply artery(27 cases) and two blood supply arteries(8 cases) in patients with malignant and borderline venereal lesions with normal diameter were higher than those of patients with benign lesions(χ2=31.765, 8.372, all P<0.05). The contrast medium through time, blood flow, blood volume and capillary surface permeability in patients with benign lesions and normal average diameter were (10.55±3.02)s, (21.54±5.58)mL·min-1·100 g-1, (4.04±0.76) mL/100 g, (10.16±2.73)mL·min-1·100 g-1, respectively, which were lower than those of patients with malignant and border venereal focal lesions (t=3.016, 5.005, 4.982, 6.989, all P<0.05). Conclusion Application of multislice spiral CT angiography in the clinical diagnosis of abdominal tumors has high accuracy and can better display the abnormal condition of blood vessels. Key words: Abdominal tumor; Tomography, spiral computed; Cineangiography; Single slice spiral CT; Invasive range; Benign lesion; Supply artery; Normal diameter; Perfusion parameters; Application value

17. Spectrum of contrast enhanced ultrasound findings in hepatocellular carcinoma treated with locoregional therapy

Background and Aims: Contrast enhanced ultrasound (CEUS) is an ultrasound imaging technique established for hepatic imaging. It has the ability to delineate the viable and non viable tissue in a malignant focal lesion [hepatocellular carcinoma (HCC)] subjected to locoregional therapy of transarterial chemoembolization, radiofrequency ablation or acetic acid ablation. We illustrate the spectrum of CEUS findings in HCC subjected to locoregional therapies. Methods: Patients who underwent locoregional therapy for focal HCC were subjected to CEUS after one month of therapy. CEUS was performed on Supersonic aixplorer ultrasound machine using ultrasound contrast (Sonovue, Bracco, Milan, Italy). About 2.4 ml of contrast was injected per nodule and the enhancement characteristics of the nodule was evaluated in 3 vascular phases- arterial (AP, at 15–25 s), venous (VP) at 45–90 s and delayed (DP, at 180 s). Cine recording was done. No enhancement or presence of any focus of enhancement in the treated tumor site was considered as complete response or residual disease (partial response) respectively as per the mRECIST criteria. The CEUS findings were co-related with multiphase computerized Tomography (MPCT)/Magnetic Resonance Imaging (MRI) liver. Results: CEUS could delineate the presence or absence of residual disease in treated patients of focal HCC. In patients with complete response, no enhancement was present at the tumor site and the entire treated tumor was seen as a well defined, uniformly hypodense lesion with smooth margins. In contrast, the residual disease (partial response) after treatment was seen as an enhancing (hyperdense) tissue located in different regions of the treated tumor. The findings were similar to that seen on MPCT or MRI liver. Conclusions: CEUS has the ability to assess therapeutic response in focal HCC subjected to locoregional therapy and the findings are akin to those seen on MPCT/MRI. The authors have none to declare.

DIAGNOSTIC IMAGING STANDARDS FOR BONE METASTASES

The purpose of the study was an attempt to create universal criteria for the diagnostic imaging of bone metastases allowing biopsy to be avoided. Material and methods. Scans from 90 patients with verified primary malignant tumors and focal bone lesions in the (n=278) were analyzed. The minimal size of the focal bone lesion was 1 cm. All patients underwent multiparameter magnetic resonance imaging with a modified scanning protocol and single-photon emission computed tomography combined with computed tomography. Diagnostic evaluation was performed before starting treatment, 1 month after starting therapy, then every 3 months for 1 year. Results. The original «principle of 8 diagnostic elements» had been created, allowing the assessment of the main pathological conditions and processes occurring in bone structures. Based on the analysis and statistic processing of 236 foci of metastatic lesion, the diagnostic informative value of each of the imaging modalities and the algorithm as a whole were assessed, and the reference values were determined. This approach allowed the accuracy of early diagnosis to be improved due to a more reliable evaluation of bone metastases at an early stage, thus reducing or completely avoiding additional biopsies.

Limitations of dual time point FDG-PET imaging in the evaluation of focal abdominal lesions.

For the evaluation of the diagnostic potential of dual time point FDG positron emission tomography (PET) in patients with suspicious focal abdominal uptake, dual time point PET imaging was compared with clinical findings. In a prospective study, 56 patients exhibiting a solitary suspicious, intense abdominal FDG uptake, underwent dual time point PET imaging for staging or restaging of different malignant tumors, maximal standardized uptake value (SUVmax) measurements included. The first acquisition was started 64.8 +/- 19.5, the second 211.3 +/- 52.5 min after FDG injection. The final diagnosis based on CT or MRT imaging and a follow-up period of 12.6 +/- 2.8 months. Additionally, colonoscopy was done in 6 patients. In another 6 patients histopathology was obtained from CT guided biopsy. Malignant focal abdominal lesions with a SUVmax <2.5 (n = 4) showed an uptake increase of > or =30%. In the remaining malignant cases with an uptake of > or =2.5 (n = 11), uptake increased in 64% and decreased in 36%. Malignant lesions showing FDG uptake decrease (n = 4) had an initial SUVmax value > or =2.5 and remained with a SUVmax > or =2.5 in the second imaging. In benign lesions with an initial SUVmax > or =2.5 (n = 31), the uptake increased in 17 patients (55%) and decreased in 14 patients (45%). All lesions which changed configuration (33%) were confirmed as benign (n = 5). Using dual time point PET abdominal lesions show a very hetergenous uptake pattern regardless of their dignity. Malignancy can only be reliably excluded in lesions which change their configuration and in lesions with an initial SUVmax value <2.5 combined with an SUV decrease in the delayed imaging. Particularly abdominal lesions which show an initial SUVmax > or =2.5 combined with a SUV increase in the delayed imaging are suspicious for malignancy and need further clarification.

Automated diagnosis of focal liver lesions using bidirectional empirical mode decomposition features

Liver is the heaviest internal organ of the human body and performs many vital functions. Prolonged cirrhosis and fatty liver disease may lead to the formation of benign or malignant lesions in this organ, and an early and reliable evaluation of these conditions can improve treatment outcomes. Ultrasound imaging is a safe, non-invasive, and cost-effective way of diagnosing liver lesions. However, this technique has limited performance in determining the nature of the lesions. This study initiates a computer-aided diagnosis (CAD) system to aid radiologists in an objective and more reliable interpretation of ultrasound images of liver lesions. In this work, we have employed radon transform and bi-directional empirical mode decomposition (BEMD) to extract features from the focal liver lesions. After which, the extracted features were subjected to particle swarm optimization (PSO) technique for the selection of a set of optimized features for classification. Our automated CAD system can differentiate normal, malignant, and benign liver lesions using machine learning algorithms. It was trained using 78 normal, 26 benign and 36 malignant focal lesions of the liver. The accuracy, sensitivity, and specificity of lesion classification were 92.95%, 90.80%, and 97.44%, respectively. The proposed CAD system is fully automatic as no segmentation of region-of-interest (ROI) is required.

Role of CT in Differentiating Malignant Focal Splenic Lesions

ObjectiveThe purpose of this study was to asses the CT findings and clinical features differentiating malignant from benign focal splenic lesions.Materials and MethodsAmong 673 patients with splenectomy, we included 114 patients with pathologically confirmed focal splenic lesions (malignant = 66, benign = 48). Two radiologists retrospectively assessed CT findings including: size, number, solid component, margin, wall, calcification, contrast-enhancement, lymph node (LN) enlargement and possible malignancy. We assessed clinical features including age, sex, underlying malignancy, fever, and leukocytosis. Multivariate logistic regression analysis was performed to identify significant predictors of malignant lesion. We used receiver operating curve analysis for determination of diagnostic performance.ResultsCommon findings of malignant lesions include enhanced, mainly solid, ill-defined margin, absence of splenomegaly, absence of the wall, absence of calcification, LN enlargement, and presence of underlying malignancy (p < 0.05). Among them, mainly solid features (odds ratio [OR], 39.098, p = 0.007), LN enlargement (OR, 6.326, p = 0.005), and presence of underlying malignancy (OR, 8.615, p = 0.001) were significant predictors of malignancy. The mean size of benign splenic lesions (5.8 ± 3.3 cm) was larger than that of malignant splenic lesions (4.0 ± 3.4 cm). Diagnostic performance of CT findings by two reviewers using receiver operating characteristic curve analysis for differentiation of malignant lesions was 0.856 and 0.893, respectively.ConclusionSolid nature of the splenic mass on CT images, LN enlargement, and presence of underlying malignancy are significant predictors of malignant splenic lesion.

Evaluation of ADCratio on liver MRI diffusion to discriminate benign versus malignant solid liver lesions

Purpose: The aim of this project is to investigate the usefulness of the absolute liver lesion ADC value and ratio of Apparent diffusion coefficient (ADC) values of a liver lesion and liver parenchyma to discriminate between a benign and malignant lesion.Methods: Liver MRI scans performed between January 2009 and June 2015 were retrospectively analysed. Scans were performed on either a 1.5 T or 3 T MRI unit. The type of liver lesion (benign or malignant) was determined by its radiological appearance, histology result and clinical management. Lesions with undetermined diagnosis or MRI studies degraded by artifacts were excluded. Liver cysts were also excluded from the analysis. ADC value of a lesion and liver parenchyma was measured and ADCratio was calculated. The values were analysed using independent samples t-testResults:Data set contained 39 benign lesions and 36 malignant lesions. Mean ADC value for benign lesions was 1678, and the mean value for malignant lesions was 1097 with a statistically significant difference of p < 0.001. All lesions with ADC value below 955 were malignant, while all lesions with ADC value above 1880 were benign. ADC value of 1260 was identified as the best available cut-off value for differentiating benign and malignant lesions, achieving sensitivity of 92%, specificity of 80% and an overall accuracy of 89%. The mean lesion to liver ADCratio for benign lesions was 1.3467 and for malignant lesions was 0.9038 with a statistically significant difference of p < 0.001. All lesions with ADCratio measuring <0.9 were malignant while lesions with ADCratio>1.5 were benign. ADCratio of 1.1 was identified statistically as the best available cut-off value for differentiating benign from malignant lesions, with sensitivity of 82%, specificity of 86% and an overall accuracy of 92%.Conclusion:Our dataset indicates that lesion to background liver ADCratio is superior in discriminating between benign and malignant focal lesions compared to absolute ADC values of the hepatic lesions.

Contrast-enhanced imaging features and differentiation of benign and malignant focal splenic lesions

To assess the value of imaging features for differentiating malignant from benign focal splenic lesions, 79 pathologically proved cases with contrast-enhanced CT or MRI were retrospectively studied. The morphological characteristics were assessed and the enhancement patterns were classified into five categories. After multivariate logistic analysis, the lesion margin and enhancement patterns were significantly different between benign and malignant lesions. The combination of ill-defined margin and hypovascular enhancement for suggesting malignant lesions had a good specificity (94.9%) and accuracy (89.9%). Morphological and enhancement characteristics on CT/MRI may be valuable in differentiating malignant from benign focal splenic lesions.

Comparison of Chemical Shift MR Imaging Findings between Vertebral Benign and Metastatic Lesions

Objectives: To establish a cut-off value for signal intensity ratio (SIR) in dual-phase chemical shift MRI and also to evaluate the sensitivity and specificity of this method in order to differentiate benign from malignant focal vertebral lesions. Methods: Totally 51 patients (28 men and 23 women) with a mean (± SD) age of 52.61 ± 13.52 years (range, 27 - 81 years) with 116 vertebral focal lesions were studied. MR imagining was performed using a 1.5-Tesla superconducting system. Chemical shift sequences for sagittal in-phase (IP) were obtained at RT/ET 100 - 165/4.2 and out-phase (OP) 100 - 165/2.4. All images were sent to a picture archiving and communication system (PACS) work station and areas with abnormal SI on the T1 and T2 sequences were identified on the IP/OP. An elliptical cursor to define region of interest was used to describe the area with abnormality on the IP and OP images. We calculated the signal intensity ratio or SIR (SI of OP/SI of IP) to compare the OP with the IP images. Air was selected as the reference contrast as not influenced by fatty infiltration. Results: SIR of 0.73 (OP images compared with IP images) can be used as the best cut-off value to identify benign (SIR < 0.73) vs. malignant (SIR ≥ 0.73) lesions with 100% sensitivity and 89.7% specificity. Conclusions: SIR values from out-phase and in-phase images (chemical shift MR imaging) may be useful for quantitatively differentiating benign from malignant focal vertebral lesions with high specificity and sensitivity. SIR values in neoplastic focal lesions were greater than benign lesion and a value of 0.73 can be used as a cut off to differentiate between benign and malignant focal lesions.

Value of Multiparametric US in the Assessment of Intratesticular Lesions.

Purpose To evaluate the diagnostic accuracy of multiparametric ultrasonography (US) consisting of gray-scale US, color Doppler US, strain elastography, and contrast agent-enhanced US in the assessment of intratesticular lesions. Materials and Methods Institutional review board approval was obtained for this retrospective study. From January 2012 to December 2015, 55 focal testicular lesions that were indeterminate on gray-scale US scans were further characterized with color Doppler US, strain elastography, and contrast-enhanced US. Strain elastography was performed to assess tissue elasticity, and hard lesions were defined as malignant. Color Doppler US and contrast-enhanced US were performed to determine the absence or presence of vascularization. Avascular lesions were defined as benign. Histopathologic results or follow-up examinations served as reference standards. Correct classification rate, sensitivity, specificity, and likelihood ratio were calculated. Results Of 55 testicular lesions, 43 (78.2%) were benign and 12 (21.8%) were malignant. Single-modality sensitivities and specificities were 66.7% and 88.4% for color Doppler US, 100% and 76.7% for contrast-enhanced US, and 100% and 72.1% for strain elastography, respectively. Among 12 malignant lesions, color Doppler US failed to demonstrate vascularization in four (33.3%) lesions, which were positive for cancer at contrast-enhanced US. By combining strain elastography and contrast-enhanced US, a sensitivity of 100% and specificity of 93.0% were achieved in differentiating benign and malignant focal testicular lesions. Positive likelihood ratio was 5.7 for color Doppler US, 4.3 for contrast-enhanced US, 3.6 for strain elastography, 14.3 for strain elastography combined with color Doppler US, and 14.3 for strain elastography combined with contrast-enhanced US. Conclusion Multiparametric US allows for a reliable differentiation of benign and malignant intratesticular lesions and can potentially be useful in deciding whether orchiectomy can be replaced with follow-up or less invasive organ-sparing strategies. © RSNA, 2017.