Malignant Focal Hepatic Lesions Research Articles

Comparison of magnetic resonance elastography and diffusion-weighted imaging for differentiating benign and malignant liver lesions

BackgroundImaging is a crucial diagnostic tool in focal liver lesions (FLLs) diagnosis. Without the need for an intravenous contrast agent, two such MRI methods that can distinguish between benign and malignant FLLs are diffusion-weighted imaging (DWI) and magnetic resonance elastography (MRE). The purpose of this study was to assess the utility of diffusion-weighted magnetic resonance imaging and magnetic resonance elastography in the identification and differentiation of benign and malignant hepatic focal lesions.MethodsThis cross-sectional study was carried out on ninety patients (with mean age 52 years) with hepatic focal lesions (29 benign and 61 malignant). Both MRE and DWI were performed on the patients. A modified gradient-echo sequence was used for MRE, and respiratory-triggered fat-suppressed single-shot echoplanar DW imaging (b = 0.800) was used for DWI. Maps of the apparent diffusion coefficient (ADC) and stiffness were produced. Regions of interest were placed over the FLLs on stiffness and ADC maps to get FLL ADC values and mean stiffness. Receiver operating curve (ROC) analysis was used to compare the roles of MRE and DWI in the differentiation of benign and malignant FLL.ResultsThe ADC of FLLs and MRE stiffness exhibited strong negative correlation [(r: −0.559; p < 0.001)]. Compared to malignant FLLs, benign FLLs had much higher mean ADC values. However, compared to benign FLLs, malignant FLLs exhibited much greater mean stiffness. FNH has the lowest mean stiffness of all FLLs, at less than 2.22 kPa. Among FLLs, CCAs had the lowest mean ADC values and the highest mean stiffness. The results showed that the MRE and DWI cutoff values were > 4.23 and ≤ 1.43, respectively; the area under the curve (AUC) values were 0.991 and 0.894, and the sensitivity and specificity results were 96.7%, 93.1%, and 85.2%, 89.7%, respectively.ConclusionsMRE was found to be more sensitive method for identifying benign and malignant hepatic focal lesions than DWI.

Role of endoscopic ultrasound and endoscopic ultrasound-guided tissue acquisition in diagnosing hepatic focal lesions.

Endoscopic ultrasonography (EUS) has become an established method in diagnostic and therapeutic procedures in gastroenterology; however, it has recently gained a growing role in hepatology. To evaluate the role of EUS features, strain elastography (SE), and EUS-tissue acquisition in diagnosing hepatic focal lesions (HFLs) that could affect further management. This cross-sectional study included 215 patients with pancreatic, biliary, or gastrointestinal malignancies referred for EUS examination. HFLs were identified in 43 patients (20%), and EUS-guided tissue acquisition was performed from these lesions. EUS features were highly sensitive (100%) but much less specific (57%) in diagnosing HFLs; the overall accuracy was 94%. Real-time elastography was also very sensitive (97%) but less specific (67%) in diagnosing HFLs; however, the overall accuracy was 92%. EUS tissue acquisition was extremely sensitive (100%) and specific (100%), with a 100% overall diagnostic accuracy. The diagnostic utility of EUS-guided tissue acquisition was extremely accurate in diagnosing HFLs. EUS characteristics and real-time SE accurately predicted the histological diagnosis of both benign and malignant HFLs.

Utility of diffusion tensor imaging in differentiating benign from malignant hepatic focal lesions.

To assess the diagnostic accuracy of diffusion tensor imaging (DTI) in the characterization of hepatic focal lesions (HFLs) and compare it to diffusion-weighted imaging (DWI). Prospective analysis was done for 49 patients (23 male and 26 female) with 74 HFLs who underwent dynamic MRI, DWI, and DTI. Apparent diffusion coefficient (ADC) values from DWI, fractional anisotropy (FA) values, and mean diffusivity (MD) values from DTI were measured by two independent radiologists. HFLs were classified into benign and malignant HFLs; the latter were subdivided into HCC and non-HCC lesions. Binary logistic regression was performed to analyze the associations between the DTI parameters and the distinction of malignant lesions. The ADC, MD, and FA at cutoff values of ≤ 1.17 × 10-3 mm2/s, ≤ 1.71 × 10-3 mm2/s, and > 0.29, respectively, are excellent discriminators for differentiating malignant and benign HFLs. The mean ADC and MD values of hemangiomas were significantly higher than HCC and non-HCC malignant lesions. In contrast, the mean FA values of hemangiomas were significantly lower than those of non-HCC malignant lesions and HCCs. The ADC and MD were very good discriminators at cutoff values of > 1.03 × 10-3 mm2/s and > 1.12 × 10-3 mm2/s, respectively. The FA at a cutoff value > 0.38 is an excellent discriminator for HCC versus non-HCC malignant lesions. Only FA value > 0.38 was a statistically significant independent predictor of HCC versus non-HCC lesions among the three parameters. There was an excellent inter-observer agreement with ICC > 0.9. MD and FA of DTI are non-invasive, very good, and excellent discriminators superior to ADC measured by DWI for the differentiation of HFLs. • The ADC, MD, and FA at cutoff values of ≤ 1.17 × 10-3 mm2/s, ≤ 1.71 × 10-3 mm2/s, and > 0.29, respectively, are excellent discriminators for differentiating malignant and benign HFLs. • The mean ADC and MD values of hemangiomas were significantly higher than those of HCC and non-HCC malignant lesions. In contrast, the mean FA values of hemangiomas were significantly lower than those of non-HCC malignant lesions and HCCs, respectively. • Multivariate regression analysis revealed that only FA value > 0.38 was a statistically significant independent predictor of HCC vs. non-HCC lesions. A lesion with FA > 0.38 has 34 times higher odds of being HCC rather than non-HCC lesions.

ROLE OF DIFFUSION WEIGHTED MRI IN ASSESSMENT OF BENIGN AND MALIGNANT HEPATIC FOCAL LESIONS IN ADULT AGE GROUP

Abstract Purpose of this study is: To evaluate the role of diffusion weighted magnetic resonance imaging in differentiation between malignant &amp; benign hepatic focal lesions. Methods The study included 38 patients all of them were with hepatic focal lesions detected by ultrasound (between 20 and 85 years of age) referred from GIT and oncology departments. Each patient included in the study was subjected to full history taking, ultrasonography and conventional MRI sequences, post Gd- DTPA dynamic and Diffusion Weighted imaging as well as ADC value measurement. Technique was performed using a standard 1.5 Tesla unit (Ingenia, Philips). Detailed MRI and laboratory investigations were done. Results The study showed significant results were obtained between ADC values of benign and malignant hepatic focal lesions (p &amp;lt; 0.001). Conclusion We concluded in this study according to the obtained results that DWI sequence together with quantitative ADC values should be used as an essential sequence to supplement the conventional MRI sequences for proper detection and characterization of hepatic focal lesions.

Apparent diffusion coefficient for differentiating between benign and malignant hepatic focal lesions

BackgroundThe aim of this study was to prospectively evaluate the role of diffusion weight MRI (DWI) in the characterization of hepatic focal lesions by using apparent diffusion coefficient (ADC). Thirty patients (18 women, 12 men; mean age 48.5 years) with hepatic focal lesions were included in this study. Patients underwent DW MR imaging with the SPLICE sequence. ADC of each focal lesion carcinoma was calculated from DW MR Images obtained with low and high b values. ADCs were compared among pathological types of focal lesions.ResultsAmong the 30 patients included in the study, 46 focal lesions were detected. Twenty-four lesions were metastatic lesions from primary cancer, 7 lesions were hepatocellular carcinoma (HCC), 9 lesions were hemangiomas, and 6 lesions were simple cysts. There was highly significant difference between the mean ADC of the malignant lesions (metastasis and HCC) and the mean ADC of benign lesions (hemangiomas and cysts). The ADC of malignant lesion was much less than that of benign lesion. The mean ADC of malignant lesions (n = 31) was 0.73 ± 0.19 × 10−3 mm2/s, and the mean ADC of benign lesions (n = 15) was 1.94 ± 0.68 × 10−3 mm2/s (p value < 0.001). There was no significant difference between the cysts and hemangiomas. There was no statistically significant difference between the metastases and hepatocellular carcinoma.ConclusionADCs values were able to differentiate benign from malignant lesions. ADC should be considered in the work up of patients with hepatic focal lesions.

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).

Role of shear wave elastography in characterization of hepatic focal lesions

BackgroundElastography is a recently developed diagnostic method that aims to evaluate tissue stiffness. Its utility is based on the fact that pathological tissues are generally stiffer than surrounding healthy tissues which often show up as a hard lesion. Shear wave elastography (SWE) is a new technique based on shear waves that has been implemented in diagnostic ultrasound (US) systems. The aim of this study is to study the role of shear wave elastography in differentiation between benign and malignant hepatic focal lesions.ResultsThe study was conducted on 110 patients (92 males, 18 females) with a mean age of 51.7 years. Age range was from 30 to 70 years; 28 patients were diagnosed with benign lesions, and 82 with malignant lesions. SWE shows that there is a significant difference in stiffness between malignant and benign lesions with p value = 0.002 and with mean ± SD of 10.3 ± 6.31 kPa for the benign lesions and 16.2 ± 9.32 kPa for the malignant group. A cutoff value of 13.24 was selected to differentiate between benign and malignant lesions using the SWE mean providing sensitivity 78.04%, specificity 71.42%, and accuracy 64.2%.ConclusionSWE is a good tool in the differentiation of benign and malignant hepatic focal lesions.

Role of diffusion weighted MRI in differentiation between benign and malignant hepatic focal lesions

Abstract Background Magnetic resonance imaging (MRI) is playing an increasing role in the assessment of patients with liver disease due to its high soft tissue resolution, lack of ionizing radiation and ability to provide functional data. Diffusion-weighted (DW)-MRI is a functional imaging technique that is now widely used as a standard imaging sequence, together with unenhanced T1/T2 weighted imaging and contrast-enhanced imaging for liver evaluation. Objective The aim of this study is to clarify the role of Diffusion Weighted Magnetic Resonance Imaging (DW MRI) in the detection of hepatic focal lesions and its ability to differentiate benign from malignant hepatic focal lesions. Patients and Methods This study carried out in Radiology Department of Ain Shams University Hospitals. This study included 25 patients. All patients were subjected to careful history taking, abdominal US, laboratory examinations, and liver MRI. Result The difference between the mean ADC values of benign and malignant lesions was significant. No significant differences in ADC values among the different benign lesions or among the different malignant lesions. Conclusion Diffusion-weighted imaging (DWI) offers the possibility to obtain criteria for characterization of focal liver lesions with subsequent differentiation between benign and malignant hepatic focal lesions without the need for contrast agent administration-by quantifying diffusion effects via apparent diffusion coefficient (ADC) measurements.

Diagnostic value of the gradient-echo in-phase and out-of-phase MRI sequence in the characterization of benign and malignant hepatic focal lesions

Background MRI is an excellent imaging modality to evaluate the liver which is vulnerable to a spectrum of neoplastic and nonneoplastic conditions. Out-of-phase T1 weighted (T1W) gradient-echo imaging is a highly accurate technique to distinguish focal hepatic steatosis from neoplastic masses. Aim This study aimed to demonstrate the diagnostic value of gradient-echo in-phase and out-of-phase MRI sequence in the characterization of benign and malignant hepatic focal lesions. Patients and methods This study is carried out on 89 patients with 100 hepatic focal lesions; their ages ranged from 32 to 76 years (mean, ±52 years), who traveled for MRI liver for the diagnosis and characterization of hepatic focal lesions. MR examination was performed including T1WI, T2WI, postcontrast dynamic enhanced T1WI followed by gradient-echo in-/out-of-phase MRI sequences. Results The 100 hepatic focal lesions proved to be: 17 focal fatty infiltration, one lipoma and eight fatty-spared area (FSA), 11 hemangioma, 10 regenerative cirrhotic nodules (RN), eight siderotic liver nodules, 12 dysplastic liver nodules, 23 hepatocellular carcinomas, seven metastatic, and three lymphoma. At conventional MRI, most of the benign hepatic focal lesions exhibit iso/hyperintense signals at T1WI and iso/hypointensity at T2WI. However, nearly all malignant lesions exhibit mainly hypointense signals at T1WI and mild hyperintensity at T2WI. At DCE T1WI: focal fatty infiltration and FSA, RN, and siderotic liver nodules take no enhancement; hemangiomas showed marginal arterial enhancement with gradual filling and there is arterial contrast enhancement with venous washout in hepatocellular carcinomas and arterial enhancement with or without washout in metastatic lesions; however, lymphomatous lesions showed temporary perilesional arterial enhancement with delayed contrast enhancement. The gradient in-/out-of-phase sequence: accurately diagnoses the all fat-containing lesions that showed moderate hyperintensity in the in-phase images and signal loss in out-of-phase images, while FSA exhibit in-phase isointensity and hyperintensity in out-of-phase images while all other benign and malignant hepatic focal lesions revealed hypointense signals in both in-/out-of-phase images. Conclusion Gradient-echo in-/out-of-phase sequence is a simple and noninvasive method that can aid in the diagnosis and characterization of benign and malignant hepatic focal lesions with 100% accuracy in the diagnosis of fat-containing lesions. Also, it can differentiate RN from dysplastic liver nodules that is considered as premalignant lesions and improve the malignant hepatic focal lesion definition.

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.

Diffusion-weighted MRI: Role in diagnosing hepatic focal lesions

Objective The objective of this study was to highlight the role of quantitative and qualitative diffusion-weighted MRI (DW-MRI) in differentiating benign and malignant hepatic focal lesions, thus increasing the efficacy of conventional hepatic MRI, in addition to evaluating the effect of using different b-values. Patients and methods This study was carried out from January to November 2016. We prospectively scanned patients with suspected liver focal lesion referred from Hepatology Unit by high-field 1.5 T MRI. The data were tabulated and manipulated using SPSS, version 14, with the level of significance set at less than 0.05. Results The study revealed that benign lesions such as simple hepatic cysts and hemangiomata showed facilitated diffusion [high signal intensity (SI) on diffusion-weighted imaging and also high SI on apparent diffusion coefficient (ADC) map], whereas malignant solid tumors such as hepatocellular carcinoma (HCC) and metastases demonstrated restricted diffusion (high SI on diffusion-weighted imaging and low SI on ADC map). Regarding the quantitative results, the mean ADC of non-neoplastic liver parenchyma, simple liver cyst, hepatic hemangioma, liver metastases, and HCC measured 1.08 ± 0.22, 2.83 ± 0.19, 2.11 ± 0.18, 1.34 ± 0.27, and 1.07 ± 0.21 × 10-3 mm2/s, respectively. There was a highly statistically significant difference in mean ADC between benign focal hepatic lesions such as hemangioma and malignant lesions such as metastases or HCC (P = 0.001). Conclusion DW-MRI is a very useful additive to conventional MRI sequences in categorizing focal hepatic lesions, thus increasing the confidence of differentiating benign and malignant lesions, particularly if there is a contraindication for contrast injection or for better detection of minute lesions adjacent to vessels.

Plasma osteopontin level as a diagnostic marker of hepatocellular carcinoma in patients with radiological evidence of focal hepatic lesions.

Hepatocellular carcinoma is one of the most aggressive malignant tumors and has limited treatment options. Needle-guided biopsies have been utilized as a tool to diagnose malignant focal hepatic lesions. These techniques are discouraged because of their complications. Nowadays, alpha fetoprotein is the most widely used tumor marker for screening and diagnosis of hepatocellular carcinoma. Nevertheless, this marker has limitations. The diagnostic role of plasma osteopontin as an adjuvant or alternative marker to alpha fetoprotein to detect hepatocellular carcinoma in Egyptian patients with focal hepatic lesions was evaluated in this study. Eighty participants were recruited from the Egyptian National Liver Institute and were self-assigned to three groups, namely, focal hepatic lesions (n = 40), liver cirrhosis (n = 20), and controls (n = 20). Participants' plasma osteopontin and serum alpha fetoprotein levels were determined and were compared across the three groups. The discriminatory ability of plasma osteopontin for hepatocellular carcinoma was lower than that of alpha fetoprotein. Osteopontin and alpha fetoprotein were not correlated with each other. Neither the gender nor the age of the patients showed a significant association with plasma osteopontin level. Measuring plasma osteopontin level alone has no advantage over serum alpha fetoprotein in patients with focal hepatic lesions due to chronic liver disease.

Assessment of hepatic focal lesions on top of cirrhotic liver using dynamic and diffusion weighted magnetic resonance imaging

AimThis work aims to assess the role of dynamic and diffusion weighted magnetic resonance imaging in diagnosis of hepatic focal lesions in cirrhotic patients. MethodsA prospective study included 30 patients (42 focal lesions) who were evaluated by dynamic contrast enhanced MRI and diffusion weighted imaging. ResultsStatistically significant difference was found between ADC values of malignant and benign hepatic focal lesions. Statistically significant difference is noticed between different types of benign hepatic focal lesions. No statistically significant difference could be detected between different types of malignant hepatic focal lesions. Dynamic MRI yields sensitivity 85%, specificity 80% and 83.3% accuracy. DW and ADC mapping revealed sensitivity 90%, specificity 90% and accuracy of 90%. ConclusionThe combination of Dynamic MRI and DW is sensitive for early detection of malignant neoplastic hepatic lesions, and for differentiation between the benign and malignant lesions.

Role of 3-T diffusion-weighted magnetic resonance imaging in differentiation between benign and malignant hepatic lesions

AimTo evaluate the ability of DWIs to distinguish between benign and malignant focal hepatic lesions (FHLs) using 3T MR. Material and methodsA total of 73 FHLs in 48 patients were evaluated. There were 28 benign lesions including 13 hemangiomas (17.8%), 8 hepatic cysts (10.9%), 4 regenerating hepatic nodules (5.4%), 2 adenomas (2.7%) and 1 focal fatty infiltration (1.3%). The others 45 lesions were malignant including 28 hepatocellular carcinomas (38.3%), 15 metastases (20.5%) and 2 cholangiocarcinomas (2.7%). The study used two b values (0 and 800s/mm2) and the ADC values were calculated. ResultsThe mean ADC value for simple liver cysts was 2.58±0.35×10−3mm2/s, for solid benign lesions was 1.63±0.41×10−3mm2/s and for malignant lesions was 1.21±0.38×10−3mm2/s with statistical difference (p<0.0001). We found that the best ADC cutoff value was 1.49×10−3mm2/s with accuracy of 83.6% in differentiation between the all benign and malignant FHLs. While with exclusion of the cystic hepatic lesions, the best ADC cutoff value was reduced to be 1.35×10−3mm2/s with accuracy of 78.5%. ConclusionsDWI can be used to differentiate between the benign and malignant FHLs.

Focal hepatic solid lesions incidentally detected on initial ultrasonography in 542 asymptomatic patients.

The purpose of this study is to evaluate the clinical significance of focal hepatic solid lesions incidentally detected on initial ultrasonography in asymptomatic patients. From January 2009 to December 2009, 2670 initial ultrasonographies were performed in asymptomatic population. Of these 2670 initial examinations, 681 focal hepatic solid lesions in 542 patients (mean 39.4 years, range 23-73 years) were detected. Clinical information, ultrasonography features, and the outcome of these lesions were analyzed. Six hundred and seventy four lesions (99.0%) in 539 patients (99.4%) were benign, while seven lesions (1.0%) in three patients (0.6%) proved to be malignant. Risk factors significantly associated with malignant focal hepatic solid lesions were known history of malignancy, history of hepatitis, a positive result for the hepatitis B surface antigen, and abnormally elevated tumor markers. No malignancy was identified in patients without any one of these four risk factors. Ultrasonographic features of internal heterogeneous echotexture with peripheral hypoechoic rim showed significant associations with malignancy. Focal hepatic solid lesions incidentally detected on initial ultrasonography were rarely malignant, especially in patients without these risk factors. Therefore, the knowledge of these risk factors and US features is important in order to make a differential diagnosis between benign and malignant focal hepatic lesions.

Clinical Translation of an Albumin-Binding PET Radiotracer 68Ga-NEB.

Suitably labeled Evans blue dye has been successfully applied to evaluate cardiac function, vascular permeability, and lymphatic imaging in preclinical settings. This study documented the first-in-human application of 68Ga-1,4,7-triazacyclononane-N,N',N″-triacetic acid (NOTA)-NEB. The NOTA-conjugated truncated form of Evans blue, NEB, was labeled with 68Ga and tested in BALB/C mice for dynamic PET and ex vivo biodistribution studies. Three healthy volunteers (2 men and 1 woman) underwent 90-min whole-body dynamic PET. The absorbed doses for major organs and whole body were calculated using OLINDA/EXM software. Eleven patients with focal hepatic lesions diagnosed by enhanced CT or MR imaging were subjected to whole-body PET/CT acquisitions at 30 min after intravenous injection of 111-148 MBq (3-4 mCi) of 68Ga-NEB. NEB dye was labeled with 68Ga (half-time, 68 min) with high yield and purity. After intravenous injection, 68Ga-NEB formed a complex with serum albumin, thus most of the radioactivity was retained in blood circulation. The tracer was demonstrated to be safe in both healthy volunteers and recruited patients without side effects or allergies. Among the 11 patients, hemangiomas showed much higher 68Ga-NEB signal intensity than the surrounding normal hepatic tissues, whereas no apparent difference between lesions and hepatic tissues was identified on 18F-FDG PET. All other focal hepatic lesions including hepatocellular carcinoma, hepatic cysts, and neuroendocrine tumor liver metastases showed negative 68Ga-NEB contrast to hepatic tissues. As a blood-pool imaging agent, 68Ga-NEB is safe to use in the clinic, and our preliminary studies demonstrate the value of differentiating hepatic hemangioma from other benign or malignant focal hepatic lesions. Easy labeling with different positron emitters of various half-lives, excellent pharmacokinetics, and imaging quality warrant further clinical applications of NEB-based PET tracers.

Role of Diffusion Weighted Magnetic Resonance Imaging in evaluation of hepatic focal lesions

ObjectiveTo clarify role of Diffusion Weighted Magnetic Resonance Imaging (DW MRI) in the detection of hepatic focal lesions and its ability to differentiate benign from malignant hepatic focal lesions. Patients and methodsThis study included 40 patients who were referred to our institution from the different medical and surgical departments as well as oncology unit. Patients with chronic renal impairment or previous allergy to the contrast media were excluded from the study. All patients were subjected to careful history taking, general and abdominal examination, laboratory examinations, and liver MRI. ResultsThe lowest ADCs were found in metastases, CCA and HCCs and the highest values were found in hemangiomas. The difference between the mean ADC values of benign and malignant lesions was significant. No significant differences in ADC values among the different benign lesions or among the different malignant lesions at both sequences. ConclusionIn conclusion, DW MRI alone performs equally well as Gd-MRI in detection and differentiation of different hepatic focal lesions. In cases where gadolinium injection is not allowed, dynamic contrast-enhanced imaging can be replaced by a protocol based on unenhanced T1 and T2 weighted imaging combined with DWI. Adding DWI to Gd-MRI is more accurate.

Combined versus single interventional therapies in treatment of hepatic malignant tumors

Aim of workTo evaluate the effectiveness of transarterial chemoembolization (TACE) combined with radiofrequency ablation (RFA) in treatment of malignant hepatic focal lesions versus use of either TACE or RFA alone. Material and methodsThe study included 57 patients; 53 with hepatocellular carcinoma (HCC), 3 with hepatic metastases, and one case with cholangiocarcinoma.They were divided into three groups according to the technique of treatment: the first group (25 patients) was treated by RF alone, the second group (17 patients) was treated by TACE alone and the third group (15 patients) was treated by combined RFA and TACE. ResultsIn cases treated with RF only there was good response in 20% of hypervascular tumors and 28% of hypovascular tumors. In cases treated with TACE there was 47.06% good response in hypervascular tumors and 11.76% in hypovascular tumors. While in combined use of TACE and RF there was 60% good response in hypervascular tumors, and 26.66% in hypovascular tumors. ConclusionCombined interventional therapies are superior to any single therapy in treatment of either hypervascular or hypovascular hepatic malignant tumors.

Added value of Gd-EOB-DTPA-enhanced Hepatobiliary phase MR imaging in evaluation of focal solid hepatic lesions

BackgroundCorrect characterization of focal solid hepatic lesions has always been a challenge and is of great diagnostic and therapeutic relevance. The purpose of this study was to determine the added value of hepatobiliary phase images in Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) for differentiating focal solid hepatic lesions.MethodsIn this retrospective trial 84 consecutive patients underwent Gd-EOB-DTPA-enhanced MR examinations. MRI was conducted for 64 patients with malignant focal hepatic lesions (34 hepatocellular carcinoma (HCC), 30 metastases) and for 20 patients with benign hepatic lesions (14 focal nodular hyperplasia (FNH), 3 adenoma, 3 hemangioma). Five radiologists independently reviewed three sets of MR images by means of a 5-point confidence scale from score 1 (definitely benign) to score 5 (definitely malignant): set 1: unenhanced images; set 2: unenhanced and Gd-EOB-DTPA-enhanced dynamic images; set 3: hepatobiliary phase images in addition to set 2. Accuracy was assessed by the alternative free-response receiver operating characteristic curve (Az) and the index of diagnostic performance was calculated.ResultsDiagnostic accuracy was significantly improved by the addition of Gd-EOB-DTPA-enhanced dynamic images: Az in set 1 was 0.708 and 0.833 in set 2 (P = 0.0002). The addition of hepatobiliary phase images increased the Az value to 0.941 in set 3 (set 3 vs set 2, P < 0.0001; set 3 vs set 1, P < 0.0001). The index of diagnostic performance was lowest in set 1 (45%), improved in set 2 (71%), and highest in set 3 (94%).ConclusionsHepatobiliary phase images obtained after Gd-EOB-DTPA-enhanced dynamic MRI improve the differentiation of focal solid hepatic lesions.

Can diffusion weighted MRI differentiate between benign and malignant hepatic focal lesions?

The aim of this study is to evaluate the role of diffusion-weighted magnetic resonance imaging in differentiation between benign and malignant hepatic focal lesions. Patients and methodsFifty-five hepatic focal lesions in 40 patients. All those patients were subjected to full clinical evaluation and radiological assessment using conventional MRI study of the liver and diffusion-weighted MRI (Different b values: 100, 500 and 750s/mm2). All lesions were evaluated regarding size, signal intensity, enhancement pattern, qualitative assessments by the different b values and quantitative assessment by measurement of the ADC values. ResultsADCs of focal hepatic lesions were significantly different between benign (2.869×10−3mm2/s±0.652) and malignant (0.995×10−3mm2/s±0. 274) hepatic focal lesions. The mean ADCs were 0.76×10−3mm2/s±0.53 for metastases, 1.3×10−3mm2/s±0.55 for HCCs, 1.95×10−3mm2/s±0.24 for benign hepatocellular lesions, 2.92×10−3mm2/s±0.102 for hemangiomas, and 3.64×10−3mm2/s±0.14 for cysts. ConclusionDiffusion-weighted imaging (DWI) offers the possibility to obtain criteria for characterization of focal liver lesions with subsequent differentiation between benign and malignant hepatic focal lesions without the need for contrast agent administration-by quantifying diffusion effects via apparent diffusion coefficient (ADC) measurements.