Diagnosis Of Liver Lesions Research Articles

Current methods of focal liver lesion diagnosis

The widespread availability of non-invasive radiological and diagnostic imaging techniques significantly contributed to the detectability of focal lesions in the liver. Ultrasonography, computed tomography (CT) multidetector CT (MDCT), conventional magnetic resonance imaging (MRI), diffusion-weighted magnetic resonance imaging (DW-MRI) and isotope imaging are used for focal liver diagnosis. This article reviews the available methods for diagnosing focal liver lesions on the basis of current literature. The diagnostic precision of a conventional ultrasound test in detecting and differentiating focal hepatic lesions is estimated at 62%. Its sensitivity for the detection of metastases ranges from 40% to 80%. If the majority of metastatic tumors are small, the sensitivity of ultrasound tests decreases dramatically to 20% for foci smaller than 1 cm. Multi-phase hepatic CT is the current standard that effectively diagnoses 63%–87% of focal changes in the liver. In many cases, standard MRI is sufficient for differentiating between benign and malignant tumors, but the results are often inconclusive. DW-MRI has emerged as a highly promising technique for oncological imaging, and it is used at various stages of oncological treatment. The discussed method does not require the administration of intravenous contrast, therefore, it is easy to repeat and useful in patients who suffer from severe renal dysfunctions and are at the risk of nephrogenic systemic fibrosis. In diagnosis of hepatic metastases, the sensitivity of 18F-FDG-PET/CT scans reaches up to 96%, and their specificity is estimated at 75%. Among various imaging techniques diffusion-weighted imaging has emerged recently as a highly promising one.

Primary liver leiomyoma: a review of this unusual tumour

Primary liver leiomyoma (PLL) should be considered in the differential diagnosis of liver lesions. A literature review has been completed and two cases are reported. The first is a 45-year-old white woman complaining of vague abdominal pain. She was initially evaluated with abdominal ultrasonography (US) that revealed a heterogeneous liver mass measuring 18 cm in greatest diameter. The tumour demonstrated hypointensity on T1-weighted and hyperintensity on T2-weighted magnetic resonance imaging. The second case is a 45-year-old Asian male who had undergone kidney transplantation 16 years ago for IgA glomerulonephritis and who developed mild, self-limiting epigastric pain. US showed a 4.3-cm-diameter lesion that was predominantly hypoechoic and was either compressing or arising from segment 2 of the liver. Computed tomography showed a well-circumscribed 4-cm-diameter mass that appeared to be arising from segments 2/3 of the liver and was adjacent to the anterior gastric wall. He underwent an uneventful laparoscopic left lateral sectionectomy and discharged on post-operative day 3. Pathological examination of the resection specimen confirmed the lesion as a PLL in each case. Herein, we report two cases of PLL and review the literature regarding this uncommon disorder.

The new generation of hepatocellular markers

In this issue, 2 groups of authors investigate the diagnostic usefulness of the immunohistochemical marker arginase‐1 in the evaluation of hepatic masses using fine‐needle aspiration. Both groups propose that arginase‐1 join 2 other immunohistochemical stains, hepatocyte paraffin and glypican‐3, which are commonly used in the often challenging diagnosis of liver lesions.

Fast 3D contrast enhanced MRI of the liver using temporal resolution acceleration with constrained evolution reconstruction

Time-resolved imaging is crucial for the accurate diagnosis of liver lesions. Current contrast enhanced liver magnetic resonance imaging acquires a few phases in sequential breath-holds. The image quality is susceptible to bolus timing errors, which could result in missing the critical arterial phase. This impairs the detection of malignant tumors that are supplied primarily by the hepatic artery. In addition, the temporal resolution may be too low to reliably separate the arterial phase from the portal venous phase. In this study, a method called temporal resolution acceleration with constrained evolution reconstruction was developed with three-dimensional volume coverage and high-temporal frame rate. Data is acquired using a stack of spirals sampling trajectory combined with a golden ratio view order using an eight-channel coil array. Temporal frames are reconstructed from vastly undersampled data sets using a nonlinear inverse algorithm assuming that the temporal changes are small at short time intervals. Numerical and phantom experimental validation is presented. Preliminary in vivo results demonstrated high spatial resolution dynamic three-dimensional images of the whole liver with high frame rates, from which numerous subarterial phases could be easily identified retrospectively.

Вивчення активності гепатоцелюлярних маркерів сироватки крові у дітей, які проживають в екологічно несприятливому районі

Проведений аналіз результатів клінічного обстеження та активності гепатоцелюлярних маркерів сироватки крові для ранньої діагностики ушкодження печінки у дітей, які проживають на території з комбінованим хімічним та радіоактивним забрудненням. Виявлено, що екопатологія в обстежених дітей має полісистемний характер, проявляючись синдромами дезадаптації, провідними з яких є гепатобіліарна патологія, патологія нирок та щитоподібної залози. Доведено, що сорбітолдегідрогеназа є більш чутливим та більш специфічним маркером діагностики ушкодження клітин печінки у дітей, які проживають в екологічно несприятливому регіоні, ніж трансамінази сироватки крові.

Hydatid cyst of the liver mimicking metastasis on FDG PET/CT scan in a patient with colon cancer

The liver is the most common site for metastatic spread in patients with colorectal carcinoma. In addition to conventional radiological investigations, F-18 FDG PET/CT is being used in staging of the colon cancer with a widely increasing manner. FDG, used in imaging, is not a tumor specific radiopharmaceutic, and it may be uptaken in many benign pathologies. This situation may sometimes cause difficulty in differential diagnosis. In this article findings of the liver cyst hydatid mimicking metastasis on FDG PET/CT scan in a case with colon cancer are presented. Hydatid cyst should be considered in differential diagnosis of liver lesions on PET scan, especially in countries where zoonotic infections are relatively common as in ours. In this case report findings that may contribute to the differential diagnosis of hydatid cyst and metastasis on FDG PET/BT scan are discussed.

Current Status of Laparoscopic Liver Resection in Korea

Since laparoscopic liver resection was first introduced in 2001, Korean surgeons have chosen a laparoscopic procedure as one of the treatment options for benign or malignant liver disease. We distributed and analyzed a nationwide questionnaire to members of the Korean Laparoscopic Liver Surgery Study Group (KLLSG) in order to evaluate the current status of laparoscopic liver resection in Korea. Questionnaires were sent to 24 centers of KLLSG. The questionnaire consisted of operative procedure, histological diagnosis of liver lesions, indications for resection, causes of conversion to open surgery, and postoperative outcomes. A laparoscopic liver resection was performed in 416 patients from 2001 to 2008. Of 416 patients, 59.6% had malignant tumors, and 40.4% had benign diseases. A total laparoscopic approach was performed in 88.7%. Anatomical laparoscopic liver resection was more commonly performed than non-anatomical resection (59.9% vs 40.1%). The anatomical laparoscopic liver resection procedures consisted of a left lateral sectionectomy (29.3%), left hemihepatectomy (19.2%), right hemihepatectomy (6%), right posterior sectionectomy (4.3%), central bisectionectomy (0.5%), and caudate lobectomy (0.5%). Laparoscopy-related serious complications occurred in 12 (2.8%) patients. The present study findings provide data in terms of indication, type and method of liver resection, and current status of laparoscopic liver resection in Korea.

Neural network based focal liver lesion diagnosis using ultrasound images

Present study proposes a computer-aided diagnostic system to assist radiologists in identifying focal liver lesions in B-mode ultrasound images. The proposed system can be used to discriminate focal liver diseases such as Cyst, Hemangioma, Hepatocellular carcinoma and Metastases, along with Normal liver. The study is performed with 111 real ultrasound images comprising of 65 typical and 46 atypical images, which were taken from 88 subjects. These images are first enhanced and then regions of interest are segmented into 800 non-overlapping segmented regions-of-interest. Subsequently 208-texture based features are extracted from each segmented region-of-interest. A two step neural network classifier is designed for classification of five liver image categories. In the first step, a neural network classifier gives classification among five liver image categories. If neural network decision is for more than one class as obtained from the first step, binary neural network classifiers are used in the second step for crisp classification between two classes. Test results of two-step neural network classifier showed correct decisions of 432 out of 500 segmented regions-of-interest in test set with classification accuracy of 86.4%. The classifier has given correct diagnosis of 90.3% (308/340) in the tested segmented regions-of-interest from typical cases and 77.5% (124/160) in tested segmented regions-of-interest from atypical cases.

Application of CT perfusion imaging in diagnosing liver cancer

Hepatic perfusion data such as hepatic blood flow, hepatic blood volume, hepatic arterial perfusion index etc, can be obtained by CT perfusion imaging (CTPI)with quantitative measurements of local blood flow to the liver. As the data mentioned above are varied in different tissues, e. g normal liver parenchyma, cirrhotic liver, hepatocellular carcinoma(HCC) and secondary liver cancer(SLC),the differential diagnosis of liver lesions, especially the early subclinical liver cancer, can be made by analyzing the related data. The principle of CTPI, the main points for differential diagnosis between HCC and SLC, the relationship between CTPI and micro-vessel density(MVD), the changes of CTPI pre-and post-TACE, as well as diagnostic sensitivity of CTPI and contrast enhanced ultrasound(CEUS) in patients with liver cancer were introduced in this article. Key words: CT perfusion imaging; Liver cancer; Diagnosis; Differential diagnosis

Improved Characterization of Focal Liver Lesions With Liver-Specific Gadoxetic Acid Disodium-Enhanced Magnetic Resonance Imaging

To evaluate the safety of gadoxetic acid disodium (Gd-EOB-DTPA) magnetic resonance imaging (MRI) and its efficacy in characterizing liver lesions. Lesion characterization and classification using combined (unenhanced and Gd-EOB-DTPA-enhanced) MRI were compared with those using unenhanced MRI and contrast-enhanced spiral computed tomography (CT) using on-site clinical and off-site blinded evaluations for patients with focal liver lesions. Gadoxetic acid disodium was well tolerated in this study. For the clinical evaluation, more lesions were correctly characterized using combined (unenhanced and Gd-EOB-DTPA-enhanced) MRI than using unenhanced MRI and spiral CT (96% vs 84% and 85%, respectively; P < or = 0.0008). For the blinded evaluation, more lesions were correctly characterized using combined MRI compared with using unenhanced MRI (61%-76% vs 48%-65%, respectively; P < or = 0.0012 for 2/3 readers); when compared with spiral CT, a similar proportion of lesions were correctly characterized. Gadoxetic acid disodium-enhanced MRI is of clinical benefit relative to unenhanced MRI and spiral CT for a radiological diagnosis of liver lesions.

Effect of a Comprehensive Image Processing on Radiologists’ Performance in Differential Diagnosis of Liver Lesions Using CT and MRI

To evaluate whether a comprehensive image processing method as CAD using CT and MRI can improve the radiologists' diagnosis performance in the differentiation of focal liver lesions. A clinical image database used in this study consists of 14 cases of each lesion including hepatic cysts, hepatocellular carcinoma (HCC), metastatic liver cancer, and hemangioma. This technique by using MR images obtained with various imaging sequences and a series of dynamic MR and dynamic CT images is designed for the enhancement of liver lesions pixel by pixel. In this method, we make the pixel sizes of MR images the same size of CT image by using tri-linear interpolation technique. Then the 3D image registration technique based on mutual information is applied for the matching of images. The image intensity pattern with and without contrast enhancement is determined as the template for the differential detection of each lesion. Pixel-by-pixel cross-correlation coefficient is calculated for the enhancement of each lesion. The radiologists' performance in distinguishing between the liver lesion was evaluated by receiver operating characteristic analysis (ROC) with a continuous rating scale. In free-response ROC analysis, true positive fractions were 75%, 87%, 85%, and 86% for hepatic cysts, HCC, metastatic liver cancer and hemangioma, respectively. Furthermore, average number of false positive and false negatives per image was 3.4 and 0.3, respectively. When radiologists made differential diagnosis of the liver lesions with the images of this technique, diagnostic accuracy was statistically significantly improved compared to the diagnostic accuracy without the images of this technique. The average area under the ROC curve (Az value) improved from 0.881 to 0.964 (p=0.069) for the differential diagnosis of hepatic cysts. Furthermore, the Az value of HCC, metastatic liver cancer, and hemangioma improved from 0.951 to 0.979 (p=0.040), from 0.946 to 0.976 (p=0.226), and from 0.966 to 0.987(p=0.045), respectively. A comprehensive image processing method as CAD using CT and MRI can improve the radiologists' diagnostic performance in the differentiation of focal liver lesions. CLINICAL RELEVANCE/APPLICATION: This method improved the performance of differential detection of liver lesions from a large number of images and it would save radiologists' reading time, and thus could assist their diagnosis.

Magnetic resonance imaging of the liver: consensus statement from the 1st International Primovist User Meeting

The role of contrastenhanced liver MRI using the hepatocyte-specific agent gadoliniumethoxybenzyl-diethylene triamine penta-acetic acid (Gd-EOB-DTPA, Primovist, Bayer Schering Pharma, Berlin, Germany) is considered, based on the discussion at the Forum of Liver MRI: The 1st International Primovist User Meeting. Current clinical evidence supports Gd-EOB-DTPA’s use in non-invasive diagnosis of benign and malignant liver lesions and staging of focal and diffuse liver disease. The information thus gained assists in the provision of cost-effective patient management. The pharmacological properties of Gd-EOB-DTPA facilitate the imaging of both the vascular and hepatobiliary phases in the cirrhotic and non-cirrhotic liver and may provide an opportunity for one-stop diagnosis of liver lesions, such as focal nodular hyperplasia, adenomas, haemangiomas, hepatocellular carcinoma and metastases. The currently recommended protocols using Gd-EOB-DTPA are appropriate for the majority of patients, but imaging time points may require modification in specific patient groups. Further experience in routine clinical practice, as opposed to that gained from rigidly designed clinical studies, may provide greater understanding of the potential of Gd-EOB-DTPA for the evaluation of the cirrhotic and non-cirrhotic liver. Additional studies may substantiate the potential of Gd-EOB-DTPA in the imaging of other abdominal organs and in the evaluation of liver function and fibrosis.

Comparison of safety and sensitivity in diagnosis of liver lesion between ultrasound-guided 16 gauges and 18 gauges core needle biopsy

To compare safety and sensitivity in diagnosis of liver lesion between ultrasound-guided 16 gauges (G) and 18 G core needle biopsy. Ultrasound-guided 16 G needle biopsy was performed in 141 patients, 77 males and 64e females, aged 51.2, and ultrasound-guided 18 G needle biopsy was performed in 105 patients, 54 males and 51 females, aged 60.1. The final diagnosis was based on the post-operative pathological examination and/or the results of 6-month follow-up. In the In the ultrasound-guided 16 G needle biopsy, 171 passes were performed with an average of 1.21 pass, a sensitivity rate of 95.9%, and a specificity rate of 100%, and abdominal pain occurred in 51 cases, and bleeding occurred in 3 cases. In the ultrasound-guided 18 G needle biopsy, 161 passes were performed with an average of 1.53 passes, a sensitivity rate of 83.8%, and a specificity rate of 100%, and abdominal pain occurred in 37 cases, and bleeding occurred in 2 cases. The number of pass of the 16 G was significantly less then that of the 128 G group (P = 0.000). The sensitivity rate of the 16 G needle biopsy was significantly higher than that of the 18 G group (P = 0.46). Ultrasound-guided 16 gauges core needle biopsy is safe for the diagnosis of hepatic disease and more sensitive than the 18 G biopsy.

Needle Tract Implantation of Hepatocellular Carcinoma After Fine Needle Biopsy

The reported incidence of needle tract implantation of hepatocellular carcinoma after fine needle biopsy ranges from 1 to 5%. We collected five cases of hepatocellular carcinoma with needle tract implantation after percutaneous biopsy and tried to determine how this complication affects the clinical outcome. From September 1997 to May 2002, five patients with needle tract implantation of hepatocellular carcinoma were managed in our institution. For treatment of the primary hepatocellular carcinoma, three patients underwent hepatectomy, one had transarterial chemoembolization, and in one patient peritoneal seeding in the needle tract precluded curative resection. All three hepatectomy patients were detected to have tumor implants in the needle tract at an interval of 39 to 58 months after biopsy. These implants were managed with wide surgical excision. Local control was achieved in two patients after repeat resection, whereas the third developed pulmonary metastasis. Thus, in two of five patients, tract implantation after fine needle biopsy changed a potentially curative disease into an untreatable situation. Because of the risk of tumor implantation in the needle tract, we support a policy of selective use of fine needle biopsy for the definitive diagnosis of liver lesions. The patients who do need a biopsy should be carefully followed up for early detection of implanted tumor and its recurrence after resection.

Comparison of CT During Arterial Portography and MR During Arterial Portography in the Detection of Liver Metastases

This study compared MR during arterial portography (MRAP) with CT during arterial portography (CTAP) with regard to the detection and differentiation of liver metastases before surgery. Fifteen patients with liver metastases were enrolled before surgery according to the guidelines of our institutional review board and good clinical practice. After mesentericography, unenhanced scans (Volume Zoom) were performed initially. For CTAP, the contrast medium was injected through the superior mesenteric artery. Images were acquired in portal and delayed enhancement. The MR protocol (1.5 T; Magnetom Symphony) started with T1-weighted fast low-angle shot (FLASH) T2-weighted turbo spin echo (TSE). MRAP followed with gadolinium-enhanced dynamic T1-weighted 3D FLASH. Delayed-phase T1-weighted 2D FLASH axial images were performed 2 min after IV injection of the contrast medium. Qualitative and quantitative evaluation of CTAP and MRAP was performed by three blinded radiologists regarding the number of lesions and their size, localization, and differential diagnosis. The overall sensitivity in detecting liver metastases was 97% with MRAP and 93% with CTAP (p > 0.05, not significant [n.s.]). The specificity was calculated to be 97% for MRAP and 82% for CTAP (p < 0.0001, statistically significant [s.s.]). The differences in sensitivity were more accentuated if only lesions 10 mm or smaller were considered (95% vs 88%, p > 0.05, n.s.), for which the respective specificities were 95% and 80% (p < 0.0014, s.s.). Improvements in sensitivity and specificity were associated with a higher lesion-to-liver contrast-to-noise ratio (59.4 +/- 51.0 for MRAP vs 10.4 +/- 7.3 for CTAP) and resulted in higher diagnostic confidence in the differential diagnosis of liver lesions (p < 0.001, s.s.) and better interobserver agreement (median kappa value, 0.88 vs 0.63). MRAP proved to be a reliable method in the preoperative detection of small liver metastases in particular, with a higher sensitivity and specificity than CTAP. If organizational difficulties of MRAP can be overcome, MRAP could be considered instead of CTAP in the preoperative invasive evaluation of metastatic liver disease.

Accuracy of frozen section in the diagnosis of liver mass lesions

Objective: To evaluate the diagnostic accuracy of intraoperative frozen sections diagnosis of liver lesions thought to be malignant tumours. Methods: 285 frozen sections of liver from 173 patients were reviewed....

Multiple von Meyenburg complexes mimicking diffuse liver metastases from esophageal squamous cell carcinoma

Von Meyenburg complexes are benign liver lesions consisting of adenomatous bile duct proliferates. We present two patients suffering from esophageal cancer accompanied by the occurrence of von Meyenburg complexes. Preoperative computerized tomography (CT) of the liver had not shown these lesions. In one of the patients, diffuse nodular manifestation was found in both liver lobes, mimicking diffuse hepatic metastases. Intraoperative frozen section revealed the benign nature of the lesions in both cases. The patients underwent esophageal resection without complications. To the best of our knowledge, the coincidence of von Meyenburg complexes and esophageal cancer has never been reported before. This uncommon entity should be taken into consideration as a differential diagnosis of liver lesions in malignancies. It underlines the importance of intraoperative frozen section for liver lesions of unknown origin.

Focal Hepatic Lesions: Diagnostic Value of Enhancement Pattern Approach with Contrast-enhanced 3D Gradient-Echo MR Imaging

Focal hepatic lesions constitute a daily challenge in the clinical setting. However, noninvasive methods can be useful in the detection and characterization of these lesions. The noninvasive diagnosis of liver lesions is usually achieved with contrast material-enhanced computed tomography and magnetic resonance (MR) imaging. Dynamic three-dimensional gradient-recalled-echo MR imaging provides dynamic contrast-enhanced thin-section images with fat saturation and a high signal-to-noise ratio and is excellent for the evaluation of various focal hepatic lesions. A comprehensive MR imaging examination in this setting includes T2-weighted and chemical shift T1-weighted imaging and demonstrates characteristic enhancement patterns that can be helpful in the diagnosis of most of these lesions. These enhancement patterns are seen during particular phases of contrast-enhanced imaging and include arterial phase enhancement, delayed phase enhancement, peripheral washout, ring enhancement, nodule-within-a-nodule enhancement, true central scar, pseudocentral scar, and pseudocapsule. Familiarity with these enhancement patterns can help in the identification of specific focal lesions of the liver.

Fat-Containing Lesions of the Liver: Cross-Sectional Imaging Findings with Emphasis on MRI

The purpose of this pictorial essay is to identify different types of liver lesions that contain fat. Cross-sectional imaging findings of fat- or lipid-containing lesions can help in characterizing focal liver lesions. We searched our archive retrospectively and reviewed the literature for fat-containing liver lesions and identified 16 different types. These lesions can contain macroscopic fat (i.e., angiomyolipoma, lipoma, liposarcoma, hydatid cyst, lipopeliosis, adrenal rest tumor, pseudolipoma, hepatic teratoma, pericaval fat, extramedullary hematopoiesis, and metastases) or intracellular lipid (i.e., focal steatosis, adenoma, focal nodular hyperplasia, regenerative nodules, and hepatocellular carcinoma). CT, MRI, and sonographic findings of these lesions can help in characterization by allowing specific diagnosis or narrowing the differential diagnosis of liver lesions.

Blood flow patterns in focal liver lesions at microbubble-enhanced US.

Noninvasive diagnosis of liver lesions is usually performed with contrast material-enhanced computed tomography (CT) and magnetic resonance (MR) imaging and is based on enhancement features of the arterial and portal venous phases. Ultrasonography (US) is often limited in characterizing liver lesions because color and spectral Doppler US provide limited vascular information in large patients and in small or deep lesions. However, microbubble contrast agents, together with specialized US techniques, now allow diagnosis of liver lesions based on morphologic evaluation of lesion vascularity and visualization of specific enhancement features. Microbubble contrast agents are purely intravascular, easy to administer, and well tolerated and allow sensitive real-time evaluation of blood flow in hepatic lesions. During the portal venous phase, benign lesions (eg, hemangioma, focal nodular hyperplasia) typically enhance more than the liver, whereas malignant lesions (eg, hepatocellular carcinoma, metastases) enhance less. Microbubble-enhanced US allows characterization of very small lesions that may not be accurately characterized with CT or MR imaging. Findings from initial studies suggest that microbubble-enhanced US of the liver provides enhancement information comparable to that provided by contrast-enhanced CT and MR imaging, along with real-time morphologic evaluation of lesion vascularity.