Solitary Necrotic Nodule of the Liver: A Benign Mimicker of Malignancy.

Solitary necrotic nodule (SNN) of the liver is an uncommon and benign finding in liver pathology. Typically, it appears as a single and asymptomatic lesion, primarily located at the subcapsular region of the right lobe of the liver. Unfortunately, it is easy to mistake this benign lesion for a primary or secondary neoplastic lesion, making it a potential diagnosis pitfall for liver malignancies. The diagnosis of SNN can be difficult to determine as the imaging findings frequently lack specificity. This brings out the importance of histomorphological examination to accurately identify this lesion, and to rule out any possible malignancies. We report here the case of a 35-year-old woman with a history of squamous cell carcinoma of the cervix, who presented a solitary nodule on her liver that was falsely diagnosed as a metastatic lesion in the liver at imagery. The aim of this article is to highlight the importance of using special stains and immunohistochemical staining for diagnosing SNN and excluding any necrotic metastases of the liver. We demonstrated that the absence of a reticulin meshwork in the necrotic core should prompt consideration of a necrotic metastasis in the liver, rather than a solitary necrotic nodule.

Development and evaluation of an integrated liver nodule diagnostic method by combining the liver segment division and lesion localization/classification models for enhanced focal liver lesion detection.

The purpose of the study was to develop a liver nodule diagnostic method that accurately localizes and classifies focal liver lesions and identifies the specific liver segments in which they reside by integrating a liver segment division algorithm using a four-dimensional (4D) fully convolutional residual network (FC-ResNet) with a localization and classification model. We retrospectively collected data and divided 106 gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance examinations into Case-sets 1, 2, and 3. A liver segment division algorithm was developed using a 4D FC-ResNet and trained with semi-automatically created silver-standard annotations; performance was evaluated using manually created gold-standard annotations by calculating the Dice scores for each liver segment. The performance of the liver nodule diagnostic method was assessed by comparing the results with those of the original radiology reports. The mean Dice score between the output of the liver segment division model and the gold standard was 0.643 for Case-set 2 (normal liver contours) and 0.534 for Case-set 1 (deformed liver contours). Among the 64 lesions in Case-set 3, the diagnostic method localized 37 lesions, classified 33 lesions, and identified the liver segments for 30 lesions. A total of 28 lesions were true positives, matching the original radiology reports. The liver nodule diagnostic method, which integrates a liver segment division algorithm with a lesion localization and classification model, exhibits great potential for localizing and classifying focal liver lesions and identifying the liver segments in which they reside. Further improvements and validation using larger sample sizes will enhance its performance and clinical applicability.

Caracterização clínica e patológica dos linfomas hepáticos: um estudo retrospetivo unicêntrico / Clinical and pathological characterization of hepatic lymphomas: a retrospective single-center study

ABSTRACT Background: The incidence of hepatic lymphoma has been increasing recently and diagnosis can be challenging as clinical presentation and radiological findings are usually variable and non-specific. Objective The aims of this study were to describe their main clinical, pathological and imaging characteristics and identify poor prognostic factors. Methods A retrospective study that included all patients with histological diagnosis of liver lymphoma over a 10-year period at our center was performed. Results A total of 36 patients were identified, with mean age of 56.6 years and male predominance (58%). There were three patients with primary liver lymphoma (8.3%) and 33 with secondary liver lymphoma (91.7%). The most common histological type was diffuse large B-cell lymphoma (33.3%). The most common clinical manifestations included fever, lymphadenopathy, weight loss, night sweats and abdominal discomfort; three patients (11.1%) were asymptomatic. Computed tomography scan revealed heterogenous radiological patterns including a single nodule (26.5%), multiple nodules (41.2%) or diffuse infiltration (32.4%). The mortality rate during follow-up was 55.6%. Higher levels of C-reactive protein (P=0.031) and absence of treatment response (P<0.001) were significantly associated with higher mortality. Conclusion Hepatic lymphoma is a rare disease that may involve liver as part of a systemic disease or, less commonly, be confined to this organ. Clinical presentation and radiological findings are often variable and non-specific. It is associated with high mortality and poor prognostic factors include higher levels of C-reactive protein and absence of response to treatment.

RESUMO Contexto A incidência de linfoma hepático tem aumentando recentemente e o diagnóstico pode ser desafiante, na medida em que a apresentação clínica e os achados imagiológicos são geralmente variáveis e inespecíficos. Objetivo: Os objetivos deste estudo foram descrever suas principais características clínicas, patológicas e de imagem e identificar fatores de mau prognóstico. Métodos: Foi realizado um estudo retrospetivo que incluiu todos os pacientes com diagnóstico histológico de linfoma hepático num período de 10 anos no nosso centro. Resultados: Foram identificados 36 pacientes, com média de idade de 56,6 anos e predomínio de género masculino (58%). Havia três pacientes com linfoma hepático primário (8,3%) e 33 com linfoma hepático secundário (91,7%). O tipo histológico mais comum foi o linfoma difuso de grandes células B (33,3%). As manifestações clínicas mais comuns incluíram febre, linfadenopatia, emagrecimento, hipersudorese noturna e desconforto abdominal; 3 (11,1%) pacientes eram assintomáticos. A tomografia computadorizada revelou padrões radiológicos heterogêneos, incluindo um único nódulo (26,5%), múltiplos nódulos (41,2%) ou infiltração difusa (32,4%). A taxa de mortalidade durante o seguimento foi de 55,6%. Níveis mais elevados de proteína C reativa (P=0,031) e ausência de resposta ao tratamento (P<0,001) foram significativamente associados a maior mortalidade. Conclusão O linfoma hepático é uma doença rara que pode envolver o fígado como parte de uma doença sistêmica ou, menos comumente, estar confinado a este órgão. A apresentação clínica e os achados radiológicos são frequentemente variáveis e inespecíficos. Associa-se a elevada mortalidade e fatores de mau prognóstico incluem níveis mais elevados de proteína C reativa e ausência de resposta ao tratamento.

Rare Hepatic Cryptococcosis Mimicked Metastatic Liver Cancer and Confirmed by Metagenomic Next-Generation Sequencing in an Immunocompetent Patient: A Case Report.

Background: Cryptococcus neoformans (C. neoformans) is commonly presented in immunocompromised individuals and causes cryptococcosis mostly in the respiratory and/or central nervous system. Liver cryptococcosis is exceedingly rare and sometimes difficult to diagnose through conventional assays. Case Presentation: The present study reports a rare case of liver cryptococcosis characterized by increased serum carbohydrate antigen 19-9 (CA19-9) level and intrahepatic multiple nodules without other symptoms in an immunocompetent woman. Her cancer family history and imaging examinations initially suspected metastatic liver malignancy. But no sign of the malignant tumor was found after endoscopy, 18-fluorine fluorodeoxyglucose positron emission tomography-computed tomography, and liver biopsy. The histopathology of the liver biopsy specimen indicated chronic inflammatory granuloma and then infectious diseases were suspected. However, traditional microbiologic testing failed to identify any potential pathogen. Eventually, metagenomic next-generation sequencing (mNGS) was applied to identify the definite diagnosis of liver cryptococcosis by acquiring the genome sequence of C. neoformans. Fortunately, after 6-month diagnostic anti-fungal therapy of fluconazole, the liver nodules effectively faded away and the serum CA19-9 level gradually regressed to the normal range. Conclusion: We identified a rare case of hepatic cryptococcosis by mNGS in an immunocompetent patient. When conventional methods have difficulties in the diagnosis of a specific pathogen, mNGS has the advantage of early and accurate identification of potential pathogens from the specimen.

Clinical and laboratory parameters associated with li-rads as diagnostic of liver nodule in patients with cirrhosis.

BACKGROUND: Hepatocellular carcinoma (HCC) is the most common primary liver cancer in the world. Clinical and laboratory evaluation of a cirrhotic patient with a liver nodule may show alterations suggesting malignancy. There is a lack of questions related to diagnosis of HCC and evaluation of liver imaging reporting and data system (LI-RADS) could be a tool for early diagnosis of HCC. This aims to confirm an association between clinical and laboratory characteristics in cirrhotic patients with hepatic nodule after LI-RADS categorization. METHODS: A cross-sectional retrospective study was performed with 62 patients grouped according to LI-RADS algorithm. Differences between groups were confirmed using association tests and the Kappa test was employed to provide further confirmation. RESULTS: Associations were observed after univariate analysis with higher values of aspartate aminotransferase (AST) (P=0.008), alanine aminotransferase (ALT) (P=0.019), alkaline phosphatase (ALP) (P=0.0052), gamma glutamyl transferase (GGT) (P=0.0023), alpha-fetoprotein (AFP) (P=0.0001), nodule size (P=0.0001) and age (P=0.007) in LR 5 group compared to LR 3. Univariate analysis also revealed higher levels for the LR5 group of ALP (P=0.0228), AFP (P=0.022) and age (P=0.046) in relation to LR 1+2 group. AFP also had higher serum levels in the LR 4 group compared to LR 1+2 (P=0.004). After multivariate analysis, higher levels in LR5 group of nodule size (P=0.047) and ALP (P=0.027) were observed in relation to LR3, and were therefore considered predictors of HCC diagnosis. CONCLUSIONS: The study suggests that the combination of clinical-laboratory and radiological factors, such as heightened serum levels of ALP and hepatic nodule size, may support the screening of HCC in cirrhotic patients with hepatic nodules using the LI-RADS algorithm.

Masquerading Hypervascular Exophytic Liver Nodule.

Patients with liver cirrhosis are at increased risk of developing hepatocellular carcinoma (HCC) and are placed on routine surveillance for HCC. Diagnosis algorithms are in place to guide clinicians in the evaluation of liver lesions detected during surveillance. Radiological assessments are critical with diagnostic criteria based on identification of typical hallmarks of HCCs on multiphasic computed tomography (CT) and dynamic contrast-enhanced magnetic resonance imaging (MRI). We report a patient with a hypervascular exophytic lesion indeterminate for HCC on CT imaging. While the detection of an exophytic arterially-enhancing lesion in an at-risk patient on CT imaging may prompt clinicians to treat the lesion as HCC without further evaluation, the patient underwent contrast-enhanced MRI with the lesion being eventually diagnosed as an exophytic haemangioma. Thus, no further action was necessary and the patient was continued on routine HCC surveillance. LEARNING POINTS: Radiological surveillance for hepatocellular carcinoma (HCC) is routine in patients at risk of HCC.Diagnosis algorithms that are in place for indeterminate lesions detected during HCC surveillance should be adhered to in order to achieve an accurate diagnosis.Sequential imaging with contrast-enhanced (gadoxetate) MRI should be used to obviate the need for an invasive biopsy when an exophytic lesion indeterminate for HCC is identified during CT imaging in a patient with liver cirrhosis, especially when a hepatic haemangioma remains a differential diagnosis.

ACR Appropriateness Criteria® Liver Lesion-Initial Characterization.

Incidental liver masses are commonly identified on imaging performed for other indications. Since the prevalence of benign focal liver lesions in adults is high, even in patients with primary malignancy, accurate characterization of incidentally detected lesions is of paramount clinical importance. This document reviews utilization of various imaging modalities for characterization of incidentally detected liver lesions, discussed in the context of several clinical scenarios. For each clinical scenario, a summary of current evidence supporting the use of a given diagnostic modality is reported. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Primary culture of aspiration residual specimens improves the diagnostic accuracy between hepatocellular carcinoma and benign nodules.

Results of fine-needle aspiration of hepatic nodules may be equivocal to confuse clinical judgment. The utility of primary culture of aspiration residual specimens to improve the accuracy in differential diagnosis between hepatocellular carcinoma and benign lesions was investigated. A total of 337 patients (hepatocellular carcinoma proven by aspiration 277, by other modalities 35, benign nodules 25) were included. The growth patterns of cancer cells at the 14th day of primary culture from aspiration proven hepatocellular carcinoma patients were applied as criteria for analysis. Hepatocellular carcinoma proven by aspiration showed higher incidence of outgrowth of cancer cells than those not proven by aspiration or the incidence of outgrowth of hepatocyte antigen positive cells in benign lesions (all P < .02). To differentiate hepatocellular carcinoma from benign nodules measuring ≤2 cm, growth patterns as item showed similar sensitivity and accuracy to aspiration results. The negative predictive values for the above two items in differential diagnosis were all below 45% in nodules measuring either ≤ or >2 cm. Using at least one positive result of growth patterns or aspiration as item for differential diagnosis increased the sensitivity, negative predictive value and accuracy, but little decreased the specificity and positive predictive value as compared with aspiration results alone in nodules measuring either ≤ or >2 cm. In conclusion, the growth patterns at the 14th day of primary culture can be applied for dynamic interpretation of the specimens to improve the diagnostic accuracy of fine-needle aspiration between hepatocellular carcinoma and benign lesions.

Toxocariasis Suspected of Having Infiltrated Directly from the Liver to the Lung through the Diaphragm.

A 37-year-old woman presented to our hospital with mild abdominal pain experienced for 2 months and hepatic nodules in segments 3 and 8. Peripheral blood eosinophilia was observed, and toxocariasis was serologically diagnosed. Seventeen days after the first imaging evaluation, a new lesion was found in segment 9 of the right lung, which was contiguous through the diaphragm to the hepatic nodule in segment 8. After treatment with albendazole, the liver and lung nodules disappeared. We suspect that larvae had directly invaded the lung from the liver, through the diaphragm.

Predictive factors of malignancy in dogs with focal liver lesions using clinical data and ultrasonographic features.

A definitive diagnosis of focal liver lesions (FLLs) requires invasive procedures for histopathologic examination. Thus, a simpler noninvasive diagnostic method, such as conventional ultrasonography combined with clinical data, is needed for the prediction of liver malignancy. The objective of this study was to examine the diagnostic accuracy of clinical data and ultrasonographic (US) features to differentiate benign and malignant liver lesions. Medical records and US images from dogs with FLLs that underwent abdominal US and histopathologic examinations following surgery or liver biopsy were retrospectively reviewed. Clinical data, including signalment, clinical signs and laboratory findings, and the US features of liver lesions that could act as predictive factors were assessed using univariate and multivariate analyses to evaluate the associations between predictive factors and liver malignancy. Based on the histopathologic results, 55 dogs with malignant lesions and 28 dogs with benign lesions were included in the study. The results of univariate analysis showed that several US features and platelet count were significantly associated with liver malignancy. Multivariate analysis revealed that the platelet count (thrombocytosis; odds ratio [OR]: 4.13, 95% confidence intervals [CI]: 1.81-9.41), lesion size (4.1 cm or greater; OR: 23.83, 95% CI: 3.74-151.95) and echotexture of FLLs (heterogenous; OR: 8.44; 95% CI: 1.37-51.91) were independent predictors for differentiating benign and malignant liver lesions, suggesting that a combination of clinical data and US findings of FLLs could predict liver malignancy in dogs.

How high is the inter-observer reproducibility in the LIRADS reporting system?

PURPOSE: To investigate the reproducibility of LIRADS v2014 and contribute to its widespread use in clinical practice. MATERIAL AND METHODS: This retrospective, single-centre study was conducted between January 2010 and October 2015. A total of 132 patients who had dynamic magnetic resonance imaging (MRI)/computed tomography (CT) images in the Picture Archiving and Communication Systems (PACS) with liver nodule were included in the study, 37 of whom had histopathology results. Five radiologists who participated in the study, interpreted liver nodules independently on different PACS stations according to the LIRADS reporting system and its main parameters. RESULTS: We determined that level of inter-observer agreement in the LR-1, LR-5, and LR-5V categories was higher than in the LR-2, LR-3, and LR-4 categories (κ = 0.522, 0.442, and 0.600 in the LR-1, LR-5, and LR-5V categories, respectively; κ = 0.082, 0.298, and 0.143 in the LR-2, LR-3, and LR-4 categories, respectively). The parameter that we observed to have the highest level of inter-observer agreement was venous thrombus (κ = 0.600). CONCLUSIONS: Our study showed that LIRADS achieves an acceptable inter-observer reproducibility in terms of clinical practice although it is insufficient at intermediate risk levels. We think that the prevalence of its use will be further increased with training related to the subject and the assignment of numerical values that express the probability of malignancy for each category and including the ancillary features in the algorithm according to clearer rules.

Enterobius vermicularis (pinworm) infection of the liver mimicking malignancy: Presentation of a new case and review of current literature.

INTRODUCTION: Enterobius vermicularis or "pinworm" infection of the liver is an extremely rare condition with only five cases previously reported in literature. It is characterized by the presence of granulomas in the liver with a necrotic core, containing adult helminthes or their ova. Because of the relatively mild symptomatology associated with this disease, prior to the arrival of modern imaging methods hepatic enterobiasis was an incidental intra-operative finding during abdominal surgery for other conditions. In recent years however, with high-resolution abdominal imaging readily available and the improved safety of hepatic resection, a lower threshold for treating suspicious hepatic nodules aggressively with surgery is being adopted. PRESENTATION OF CASE: We present the second case in international literature, where E. vermicularis of the liver was mistaken for malignancy and led to hepatic resection and perform a literature review of the five previously documented cases of hepatic enterobiasis. DISCUSSION: Our report identifies certain trends in this condition's aetiology and clinical behaviour, but due to its rarity definitive answers cannot yet be established. CONCLUSION: We do not advocate a change in the current approach of suspicious hepatic nodules, but we do feel that better understanding of the mechanisms involved with hepatic enterobiasis could, in the future, prevent unnecessary surgery.

Morphological and functional MDCT: problem-solving tool and surrogate biomarker for hepatic disease clinical care and drug discovery in the era of personalized medicine.

This article explains the significant role of morphological and functional multidetector computer tomography (MDCT) in combination with imaging postprocessing algorithms served as a problem-solving tool and noninvasive surrogate biomarker to effectively improve hepatic diseases characterization, detection, tumor staging and prognosis, therapy response assessment, and novel drug discovery programs, partial liver resection and transplantation, and MDCT-guided interventions in the era of personalized medicine. State-of-the-art MDCT depicts and quantifies hepatic disease over conventional CT for not only depicting lesion location, size, and extent but also detecting changes in tumor biologic behavior caused by therapy or tumor progression before morphologic changes. Color-encoded parameter display provides important functional information on blood flow, permeability, leakage space, and blood volume. Together with other relevant biomarkers and genomics, the imaging modality is being developed and validated as a biomarker to early response to novel, targeted anti-VEGF(R)/PDGFR or antivascular/angiogenesis agents as its parameters correlate with immunohistochemical surrogates of tumor angiogenesis and molecular features of malignancies. MDCT holds incremental value to World Health Organization response criteria and Response Evaluation Criteria in Solid Tumors in liver disease management. MDCT volumetric measurement of future remnant liver is the most important factor influencing the outcome of patients who underwent partial liver resection and transplantation. MDCT-guided interventional methods deliver personalized therapies locally in the human body. MDCT will hold more scientific impact when it is fused with other imaging probes to yield comprehensive information regarding changes in liver disease at different levels (anatomic, metabolic, molecular, histologic, and other levels).

Epithelioid Hemangioendothelioma of the Liver: Helical CT Findings

PURPOSE: To describe the morphologic features and enhancement patterns of the helical computed tomography (CT) observed in patients with epithelioid hemangioendothelioma (EH) of the liver. MATERIALS AND METHODS: Seven patients (four men and three women; mean age, 41 years) with pathologically proven EHs underwent monophasic (n=2), biphasic (n=2) or triphasic (n=3) helical CT, and the findings were retrospectively analysed. The morphologic features to which attention was directed were tumor number, size, location, shape, margin, surface, the presence of adjacent capsular retraction, vascular encasement and confluent mass formation, while the enhancement pattern was examined in terms of the appearance and degree of enhancement during the arterial or portal phase, and enhancement change during the portal and equilibrium phases. RESULTS: Six patients had multiple tumors, and one had a single lesion. The maximon diameter of these tumors ranged from 0.5 to 12.0 (mean, 3.2) cm, and almost all occurred in the peripheral portion of the liver. The shape, margin and surface features of the tumors varied: in four patients, the margin was poorly defined and the surface was smooth, while in five, adjacent capsular retraction was observed. Vascular encasement was noted in five of six patients with hepatic vessels abutting the tumors, and in all three who were follow up, the growth pattern involved confluent mass formation. In all patients, many tumors showed either nodular (n=3) or irregular (n=4) peripheral enhancement. In all five patients who underwent multiphasic CT, centripetal enhancement was demoustrated. CONCLUSION: Our results disclosed that most patients with EH had multiple tumors, and that almost all were located in the peripheral portion of the liver and involved capsular retraction. The other common CT findings were vascular encasement and a centripetal enhancement pattern. When these CT findings are observed in patients with hepatic tumors, EH should be included in the differential diagnosis.

Adenomatous Hyperplasia of the Liver: Triple-phase Helical CT Findings

PURPOSE: To evaluate the triple-phase helical CT findings of adenomatous hyperplasia of the liver. MATERIALS AND METHODS: Forty-seven cases of adenomatous hyperplasias (size range: 8 -45 mm, mean: 14mm) in nineteen patients were confirmed by histologic examination following surgery (n=32) or gun biopsy (n=15) and formed the basis of this study. All patients underwent helical CT scanning involving the injection of 100mL nonionic contrast material at a rate of 3mL/sec. Hepatic arterial, portal venous, and equilibrium phase CT images were obtained 30, 60, and 180 seconds, respectively, after the start of contrast injection. The attenuation of each nodule (hyper-, iso-, hypo-, or mixed) was retrospectively determined and the detection rate according to lesion size (> or =14mm or or =14mm) and 76 % (16/21) in the large size group(< 14mm). This rate was thus significantly higher in the large size group than in that in which lesions were small. CONCLUSION: Triple -phase helical CT revealed that in cases of adenomatous hyperplasia, attenuation was variable,with iso-attenuation the most frequent type. Seventy-six percent of nodules larger than 14 mm were detected. Adenomatous hyperplasia may be seen during the hepatic arterial phase as a hyper-attenuated nodule.