Current update on vaginal malignancies

Primary vaginal cancers are rare and account for 1-3% of all gynecologic malignancies. There are several histological subtypes that affect a wide range of the population. Imaging plays an important role in the diagnosis, staging, and treatment planning of vaginal cancers. This article reviews the relevant anatomy, clinical findings, imaging characteristics, and recent advances in the management of vaginal malignancies.

Multimodality Imaging and Genetics of Primary Mucosal Melanomas and Response to Treatment

Mucosal melanomas (MMs) are rare and aggressive tumors that arise from melanocytes in the mucosal tissues that line the respiratory, gastrointestinal, and urogenital tracts. Most MMs occur during the 6th and 7th decades of life. MMs may be asymptomatic but may also cause bleeding, pain, and itching, depending on the site of origin. Because of their asymptomatic or oligosymptomatic nature and the difficulty of visualizing them in some cases, they are often advanced tumors at patient presentation. MM staging varies depending on the site of the primary tumor. A simplified staging system allows classification of clinically localized disease as stage I, regional nodal involvement as stage II, and distant metastasis as stage III. MM differs genetically from its cutaneous counterparts. Common drivers in cutaneous melanoma such as B-raf proto-oncogene serine/threonine kinase (BRAF) have a lower mutation rate in MM, whereas mutations of other genes including the KIT proto-oncogene, receptor tyrosine kinase (KIT) and splicing factor 3b subunit 1 gene (SF3B1) are more common in MM. Complete resection is the best curative option. However, surgical intervention with wide local excision and negative margins may be difficult to attain because of the local anatomy and the extent of disease. In addition, despite aggressive surgical resection, most patients develop local recurrence and metastatic disease. Recent advances in the treatment of melanoma include immunotherapy and targeted therapy. Unfortunately, MMs have a relatively poor prognosis, with an overall 5-year survival rate of 25%. Online supplemental material is available for this article. ^©RSNA, 2021.

Peer Learning and Operationalizing During COVID-19 Pandemic and Beyond

The main objective of the article is to describe the changes in managing the peer learning system in the Department of Abdominal Imaging at our institution during the pandemic and its restrictions. The pandemic poses diverse challenges to academic institutions across the country including radiology education and peer learning. The health sector in some areas of the country has been stretched by the number of coronavirus disease 2019 (COVID-19) patients. In March 2020, our institution cancelled all in-person conferences as per guidelines from the Center of Disease Control and Prevention to mitigate the spread of COVID-19 and the conferences were shifted to virtual platforms. Our recent peer learning approach allowed us to practice appropriate social distancing while following the institutional and national guidelines with minimal disruption. Other institutions that are facing similar challenges can adopt or modify our framework of a successful and efficient virtual peer learning process.

Technologic optimization of a virtual disease focused panel during the COVID pandemic and beyond

Since the beginning of the COVID-19 pandemic, several service fields have opted for virtual work as much as possible, in order to decrease the spread of the virus. Although several articles have now addressed the key issues in telecommunications and medical education, none have described the digital or virtual functionality of a professional society disease focused panel (DFP) or inter-institutional collaborations. This is extremely important as we believe that the virtual functioning of the DFP will be the new norm for years to come. In this article, we highlight the limitations in the functioning of DFP brought forth due to the ongoing pandemic, while also providing the digital technologic solutions to adapt and also maintain or increase its productivity.

Novel deep learning-based noise reduction technique for prostate magnetic resonance imaging

Introduction

Magnetic resonance imaging (MRI) has played an increasingly major role in the evaluation of patients with prostate cancer, although prostate MRI presents several technical challenges. Newer techniques, such as deep learning (DL), have been applied to medical imaging, leading to improvements in image quality. Our goal is to evaluate the performance of a new deep learning-based reconstruction method, “DLR” in improving image quality and mitigating artifacts, which is now commercially available as AIR^TM Recon DL (GE Healthcare, Waukesha, WI). We hypothesize that applying DLR to the T2WI images of the prostate provides improved image quality and reduced artifacts.

Methods

This study included 31 patients with a history of prostate cancer that had a multiparametric MRI of the prostate with an endorectal coil (ERC) at 1.5 T or 3.0 T. Four series of T2-weighted images were generated in total: one set with the ERC signal turned on (ERC) and another set with the ERC signal turned off (Non-ERC). Each of these sets then reconstructed using two different reconstruction methods: conventional reconstruction (Conv) and DL Recon (DLR): ERC_DLR, ERC_Conv, Non-ERC_DLR, and Non-ERC_Conv. Three radiologists independently reviewed and scored the four sets of images for (i) image quality, (ii) artifacts, and (iii) visualization of anatomical landmarks and tumor.

Results

The Non-ERC_DLR scored as the best series for (i) overall image quality (p < 0.001), (ii) reduced artifacts (p < 0.001), and (iii) visualization of anatomical landmarks and tumor.

Conclusion

Prostate imaging without the use of an endorectal coil could benefit from deep learning reconstruction as demonstrated with T2-weighted imaging MRI evaluations of the prostate.

Ovarian teratomas: clinical features, imaging findings and management

Ovarian teratomas are the most common type of germ cell tumors. There are three major subtypes of ovarian teratomas including mature, immature, and monodermal teratomas. Ultrasound, computed tomography and magnetic resonance imaging can demonstrate specific imaging findings for mature teratoma. Imaging features of immature and monodermal teratomas are less specific, but a combination of clinical features and imaging findings can help in the diagnosis. Imaging is also very helpful in guiding management. In this article, we review the epidemiology, histopathology, clinical presentation, imaging features and management of ovarian teratomas.

Radiographic and Serologic Predictors of Pathologic Major Response to Preoperative Therapy for Pancreatic Cancer

OBJECTIVE

We sought to identify potential radiologic and serologic markers of pancreatic tumor response to therapy, using pathologic major response (pMR) as the objective endpoint.

BACKGROUND

We previously demonstrated that a pMR to preoperative therapy, defined as detection of <5% viable cancer cells in the surgical specimen on histopathological analysis, is an important prognostic factor for patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

Pretreatment and posttreatment computed tomography scans of consecutive patients who received preoperative chemotherapy and/or (chemo)radiation before pancreatectomy for PDAC between January 2010 and December 2018 were rereviewed. Response per Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, other radiographic changes in tumor size and anatomic extent, and posttreatment CA 19-9 levels were compared between patients who did and did not have a pMR on final histopathologic analysis of their surgical specimens.

RESULTS

A total of 290 patients with localized PDAC underwent pancreatectomy between 2010 and 2018 after receiving preoperative chemotherapy (n = 36; 12%), (chemo)radiation (n = 87; 30%), or both (n = 167; 58%). Among them, 28 (10%) experienced pMR, including 9 (3.1%) who experienced pathologic complete response. On multivariable logistic regression, low posttreatment CA 19-9 level, RECIST partial response, and reduction in tumor volume were confirmed to be independently associated with pMR (P < 0.01).

CONCLUSIONS

We identified serologic and radiographic indicators of pMR that could help inform the delivery of preoperative therapy to patients with PDAC.

A Phase I Dose-Escalation Study to Evaluate the Safety and Tolerability of Evofosfamide in Combination with Ipilimumab in Advanced Solid Malignancies

PURPOSE

As hypoxia can mediate resistance to immunotherapy, we investigated the safety, tolerability, and efficacy of combining evofosfamide, a prodrug that alleviates hypoxia, with ipilimumab, an immune checkpoint inhibitor, in immunologically "cold" cancers, which are intrinsically insensitive to immunotherapy, as well as in "hot/warm" metastatic cancers that are, atypical of such cancers, resistant to immunotherapy.

PATIENTS AND METHODS

In a phase I, 3+3 dose-escalation trial (NCT03098160), evofosfamide (400-640 mg/m²) and ipilimumab (3 mg/kg) were administered in four 3-week cycles. The former was administered on days 1 and 8 of cycles 1-2, while the latter was administered on day 8 of cycles 1-4. Response was assessed using immune-related RECIST and retreatment was allowed, if deemed beneficial, after completion of cycle 4 or at progression.

RESULTS

Twenty-two patients were enrolled, of whom 21 were evaluable, encompassing castration-resistant prostate cancer (n = 11), pancreatic cancer (n = 7), immunotherapy-resistant melanoma (n = 2), and human papillomavirus-negative head and neck cancer (n = 1). Drug-related hematologic toxicities, rash, fever, nausea, vomiting, and elevation of liver enzymes were observed in > 10% of patients. The most common drug-related grade 3 adverse event was alanine aminotransferase elevation (33.3%). Two patients discontinued ipilimumab and 4 required evofosfamide deescalation due to toxicity. Of 18 patients with measurable disease at baseline, 3 (16.7%) achieved partial response and 12 (66.7%) achieved stable disease. The best responses were observed at 560 mg/m² evofosfamide. Preexisting immune gene signatures predicted response to therapy, while hypermetabolic tumors predicted progression. Responders also showed improved peripheral T-cell proliferation and increased intratumoral T-cell infiltration into hypoxia.

CONCLUSIONS

No new or unexpected safety signals were observed from combining evofosfamide and ipilimumab, and evidence of therapeutic activity was noted.

Liver Fibrosis Assessment

Early diagnosis of hepatic fibrosis (HF) is pivotal for management to cease progression to cirrhosis and hepatocellular carcinoma. HF is the telltale sign of chronic liver disease, and confirmed by liver biopsy, which is an invasive technique and inclined to sampling errors. The morphologic parameters of cirrhosis are assessed on conventional imaging such as on ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI). Newer imaging modalities such as magnetic resonance elastography and US elastography are reliable and accurate. More research studies on novel imaging modalities such as MRI with diffusion weighted imaging, enhancement by hepatobiliary contrast agents, and CT using perfusion are essential for earlier diagnosis, surveillance and accurate management. The purpose of this article is to discuss non-invasive CT, MRI, and US imaging modalities for diagnosis and stratify HF.

What's New in Hepatic Steatosis

Hepatic steatosis can lead to liver cancer, cirrhosis, and portal hypertension. There are two main types, non-alcoholic fatty liver disease (NAFLD) and alcoholic liver disease. The detection and quantification of hepatic steatosis with lifestyle changes can slow the evolution from NAFLD to steatohepatitis. Currently, the gold standard for the quantification of fat in the liver is biopsy, has some limitations. Hepatic steatosis is frequently detected during cross sectional imaging. Ultrasound (US), Computed Tomography (CT), and Magnetic Resonance Imaging (MRI) provide noninvasive assessment of liver parenchyma and can detect fat infiltration in the liver. However, the non-invasive quantification of hepatic steatosis by imaging has been challenging. Recent MRI techniques show great promise in the detection and quantification of liver fat. The aim of this article is to review the utilization of non-invasive imaging modalities for the detection and quantification of hepatic steatosis, to evaluate their advantages and limitations.

Effect of sarcopenia on systemic targeted therapy response in patients with advanced hepatocellular carcinoma

PURPOSE

Sarcopenia is an independent prognostic indicator for hepatocellular carcinoma (HCC). Our objective was to determine the effect of sarcopenia on response to systemic targeted therapy in patients with advanced HCC.

MATERIALS AND METHODS

This was a retrospective, Institutional Review Board approved study of 36 patients on systemic targeted therapy with immune checkpoint blockade (n = 25) or tyrosine kinase inhibitor (n = 11) for biopsy-proven advanced HCC. Skeletal muscle index (SMI) was calculated from erector spinae muscle area (SMA) at the level of T12 on pretreatment CT: [SMI = SMA (cm2)/height (m2)]. SMI was compared to treatment response defined as overall survival ≥ 1 year (nonsurgical patients) or > 50% HCC necrosis (surgical patients). Receiver operating characteristic curve and area under the curve was used for analysis with p < 0.05 for statistical significance.

RESULTS

Median age of men and women was 66.5 years (range 32-83) and 70 years (range 54-78), respectively. Liver disease etiology was nonalcoholic steatohepatitis (n = 9), hepatitis C (n = 10), hepatitis B (n = 5), alcohol (n = 3) and unknown (n = 9). Mean (± SD) height and SMI for men were 1.7 m (± 0.1) and 11.4 (± 3.6); values for women were 1.7 m (± 0.1) and 8.2 (± 1.9). Treatment was withdrawn in five patients due to treatment intolerance. Response occurred in 10/31 (32.3%) patients (23 men, 8 women). T12SMI correlated with treatment response using a threshold of 7.21-8.23 for women (AUC = 1; p = 0.037), and 11.47 for men (AUC = 0.83; p = 0.015); correlation was increased for men ≥ 60 years, (AUC = 0.87; p = 0.023).

CONCLUSION

Sarcopenia was associated with reduced survival and HCC necrosis in patients treated with systemic targeted therapy.

CLINICAL RELEVANCE

Sarcopenia may help in predicting outcomes to targeted therapy in advanced HCC.

Predictive Modeling for Voxel-Based Quantification of Imaging-Based Subtypes of Pancreatic Ductal Adenocarcinoma (PDAC): A Multi-Institutional Study

Previously, we characterized qualitative imaging-based subtypes of pancreatic ductal adenocarcinoma (PDAC) on computed tomography (CT) scans. Conspicuous (high delta) PDAC tumors are more likely to have aggressive biology and poorer clinical outcomes compared to inconspicuous (low delta) tumors. Here, we developed a quantitative classification of this imaging-based subtype (quantitative delta; q-delta). Retrospectively, baseline pancreatic protocol CT scans of three cohorts (cohort#1 = 101, cohort#2 = 90 and cohort#3 = 16 [external validation]) of patients with PDAC were qualitatively classified into high and low delta. We used a voxel-based method to volumetrically quantify tumor enhancement while referencing normal-pancreatic-parenchyma and used machine learning-based analysis to build a predictive model. In addition, we quantified the stromal content using hematoxylin- and eosin-stained treatment-naïve PDAC sections. Analyses revealed that PDAC quantitative enhancement values are predictive of the qualitative delta scoring and were used to build a classification model (q-delta). Compared to high q-delta, low q-delta tumors were associated with improved outcomes, and the q-delta class was an independent prognostic factor for survival. In addition, low q-delta tumors had higher stromal content and lower cellularity compared to high q-delta tumors. Our results suggest that q-delta classification provides a clinically and biologically relevant tool that may be integrated into ongoing and future clinical trials.

Correlation of surgeon radiology assessment with laparoscopic disease site scoring in patients with advanced ovarian cancer

BACKGROUND

Radiographic triage measures in patients with new advanced ovarian cancer have yielded inconsistent results.

OBJECTIVE

To determine the correlation between surgeon radiology assessment and laparoscopic scoring by disease sites in patients with newly diagnosed advanced stage ovarian cancer.

METHODS

Fourteen gynecologic oncology surgeons from a single institution performed a blinded review of pre-operative contrast-enhanced CT imaging from patients with advanced stage ovarian cancer. Each of the patients had also undergone laparoscopic scoring assessment, between April 2013 and December 2017, to determine primary resectability using the validated Fagotti scoring method, and assigned a predictive index value score. Surgeons were asked to provide expected predictive index value scores based on their blinded review of the antecedent CT imaging. Linear mixed models were conducted to calculate the correlation between radiologic and laparoscopic score for surgeons individually, and as a group. Once the model was fit, the inter-class correlation and 95% CI were calculated.

RESULTS

Radiology review was performed on 20 patients with advanced stage ovarian cancer who underwent laparoscopic scoring assessment. Surgeon faculty rank included assistant professor (n=5), associate professor (p=4), and professor (n=5). The kappa inter-rater agreement was -0.017 (95% CI -0.023 to -0.005), indicating low inter-rater agreement between radiology review and actual laparoscopic score. The inter-class correlation in this model was 0.06 (0.02-0.21), indicating that surgeons do not score the same across all the images. When using a clinical cut-off point for the predictive index value of 8, the probability of agreement between radiology and actual laparoscopic score was 0.56 (95% CI 0.49 to 0.73). Examination of disease site sub-scales showed that the probability of agreement was as follows: peritoneum 0.57 (95% CI 0.51 to 0.62), diaphragm 0.54 (95% CI 0.48 to 0.60), mesentery 0.51 (95% CI 0.45 to 0.57), omentum 0.61 (95% CI 0.55 to 0.67), bowel 0.54 (95% CI 0.44 to 0.64), stomach 0.71 (95% CI 0.65 to 0.76), and liver 0.36 (95% CI 0.31 to 0.42). The number of laparoscopic scoring cases, tumor reductive surgery cases, or faculty rank was not significantly associated with overall or sub-scale agreement.

CONCLUSIONS

Surgeon radiology review did not correlate highly with actual laparoscopic scoring assessment findings in patients with advanced stage ovarian cancer. Our study highlights the limited accuracy of surgeon radiographic assessment to determine resectability.

Response to re-challenge of a MEK inhibitor in a patient with recurrent low-grade serous carcinoma of the peritoneum

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Low-grade serous carcinoma is relatively resistant to chemotherapy.

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MEK inhibitors have promising activity in recurrent low-grade serous carcinoma.

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The first case of successful re-challenge with a MEK inhibitor is presented.

Low-grade serous carcinoma of the ovary/peritoneum is a rare epithelial cancer subtype characterized by younger age at diagnosis, relative chemoresistance, and prolonged overall survival compared with high-grade serous carcinoma. In addition, alterations in the mitogen activated protein kinase pathway are frequent and play a major role in the pathogenesis of this tumor. MEK inhibitors have demonstrated promising activity in the treatment of recurrent low-grade serous carcinoma. Although prevailing wisdom in cancer therapy is that the re-treatment with a drug after emergence of resistance is futile, we report the initial case of a patient with recurrent low-grade serous carcinoma who experienced a partial response when re-challenged with a MEK inhibitor after previously having prolonged stable disease followed by disease progression on a MEK inhibitor.

Intrahepatic cholangiocarcinoma: pathogenesis, current staging, and radiological findings

To this date, it is a major oncological challenge to optimally diagnose, stage, and manage intrahepatic cholangiocarcinoma (ICC). Imaging can not only diagnose and stage ICC, but it can also guide management. Hence, imaging is indispensable in the management of ICC. In this article, we review the pathology, epidemiology, genetics, clinical presentation, staging, pathology, radiology, and treatment of ICC.

Correction to: Imaging spectrum of mesenteric masses

The original version of this article unfortunately contained a mistake. The author list was not correct in the original article. The missing co-author's name, Sherif Elsheif, has been added to show the correct and complete author list. All authors and the Editor-in-Chief agreed to the corrected author list. The original article has been corrected.

"Renal emergencies: a comprehensive pictorial review with MR imaging"

Superior soft-tissue contrast and high sensitivity of magnetic resonance imaging (MRI) for detecting and characterizing disease may provide an expanded role in acute abdominal and pelvic imaging. Although MRI has traditionally not been exploited in acute care settings, commonly used in biliary obstruction and during pregnancy, there are several conditions in which MRI can go above and beyond other modalities in diagnosis, characterization, and providing functional and prognostic information. In this manuscript, we highlight how MRI can help in further assessment and characterization of acute renal emergencies. Currently, renal emergencies are predominantly evaluated with ultrasound (US) or computed tomography (CT) scanning. US may be limited by various patient factors and technologist experience while CT imaging with intravenous contrast administration can further compromise renal function. With the advent of rapid, robust non-contrast MRI, and magnetic resonance angiography (MRA) imaging studies with short scan times, free-breathing techniques, and lack of ionization radiation, the utility of MRI for renal evaluation might be superior to CT not only in diagnosing an emergent renal process but also by providing functional and prognostic information. This review outlines the clinical manifestations and the key imaging findings for acute renal processes including acute renal infarction, hemorrhage, and renal obstruction, among other entities, to highlight the added value of MRI in evaluating the finer nuances in acute renal emergencies.

Endometrial Cancer, the Current International Federation of Gynecology and Obstetrics Staging System, and the Role of Imaging

Imaging plays a crucial role in the diagnosis, staging, and follow-up of endometrial cancer. Endometrial cancer is staged surgically using the International Federation of Gynecology and Obstetrics (FIGO) staging system. Preoperative imaging can complement surgical staging but is not yet considered a required component in the current FIGO staging system. Preoperative imaging can help identify some tumor characteristics and tumor spread, both locally and distally. More accurate assessment of endometrial cancers optimizes management and treatment plan, including degree of surgical intervention. In this article, we review the epidemiology, FIGO staging system, and the importance of imaging in the staging of endometrial cancer.

Imaging spectrum of NUT carcinomas

Nuclear protein of the testis (NUT) carcinoma (NC) (formerly known as NUT midline carcinoma) is an aggressive pleomorphic squamous cell carcinoma with a dismal prognosis. Primary NC tumors are commonly located in the chest or head and neck regions. Imaging plays an indispensable role in the staging, management, treatment response assessment, and surveillance of NC. Primary pulmonary NC usually presents as a large mass with lymphadenopathy and pleural involvement. Primary head and neck NC presents as a large expansile necrotic mass in the sinonasal region with locoregional destruction and occasional cervical lymph node involvement. These imaging features are relatively non-specific but are consistent among patients. Currently, there are no standardized guidelines for the treatment of NC. Because of its rarity, paucity of reports in the medical literature, and the lack of awareness among radiologists, NUT carcinoma (NC) has been largely underdiagnosed and misdiagnosed. Clinical aggressive features and pleomorphic/undifferentiated squamous cell carcinoma should prompt genetic evaluation for NUT translocation to diagnose NC. In this article, we discuss NC's clinicopathologic and imaging features and treatment options, including emerging new treatments.

Difficulties in differentiating between checkpoint inhibitor pneumonitis and lung metastasis in a patient with melanoma

The use of immune checkpoint inhibitors is associated with significant toxicities such as pneumonitis; the clinical presentation of the latter can be misleading and may mimic metastasis. We report the case of a melanoma patient who developed late-onset pneumonitis after discontinuation of treatment with anti-programmed cell death protein 1 (PD1) and anti-cytotoxic T lymphocyte antigen 4 (CTLA4) (patient had a complete response). The patient was asymptomatic, however, surveillance computed tomography (CT) scan showed a growing lung nodule and several new-onset, small lung lesions highly suspicious for recurrence. A biopsy of the lesions revealed organizing pneumonia with absence of malignant cells. The lung lesions completely resolved after 6 months without any intervention. The patient is still in complete remission 2 years after the initial diagnosis of melanoma.

Quantitative attenuation accuracy of virtual non-enhanced imaging compared to that of true non-enhanced imaging on dual-source dual-energy CT

PURPOSE

To evaluate the quantitative attenuation and reliability of virtual non-contrast (VNC) images of the abdomen acquired from multiphasic scans with a dual-energy computed tomography (DECT) system and compare it with that of true non-enhanced images (TNC) on second- (Flash) and third- (Force) generation DECT scanners.

METHODS

This retrospective study was approved by the institutional review board and included 123 patients with pancreatic cancer who had undergone routine clinical multiphasic DECT examinations at our institution using Flash and Force scanners between March and August 2017. VNC images of the abdomen were reconstructed from late arterial phase images. For every patient, regions-of-interest were defined in the aorta, fluid-containing structures (gallbladder, pleural effusion, and renal cysts > 10 mm), paravertebral muscles, subcutaneous fat, spleen, pancreas, renal cortex, and liver (eight locations) on TNC and VNC images. The mean attenuation of VNC was compared with TNC by organ for each CT scanner using an equivalence test and the Bland-Altman plot. The mean attenuations for TNC or VNC were compared between the Force and Flash CT scanners using a two-sample t test.

RESULTS

The VNC attenuation of organs on the Force scanner was lower than was that on the Flash, and the mean attenuation difference in different organs on the Force was closer to 0. The estimated means of TNC and VNC were equivalent for an equivalence margin of 10 on the Force scanner.

CONCLUSION

VNC images in DECT are a promising alternative to TNC images. In clinical scenarios in which non-enhanced CT images are required but are not available for accurate diagnosis, VNC images can potentially serve as an alternative to TNC images without the radiation exposure risks.

Hepatic Hemangioendothelioma: An update

Primary epithelioid hemangioendotheliomas of the liver (EHL) are rare tumors with a low incidence. The molecular background of EHL is still under investigation, with WWTR1-CAMPTA1 mutation may function as a tumor marker. Commonly, this tumor is misdiagnosed with angiosarcoma, cholangiocarcinomas, metastatic carcinoma, and hepatocellular carcinoma (sclerosing variant). Characteristic features on imaging modalities such as ultrasound, computed tomography, magnetic resonance imaging and positron emission tomography/computed tomography guide in diagnosis and staging. The "halo sign" and the "lollipop sign" on computed tomography and magnetic resonance imaging are described in the literature. Currently, there are no standardized guidelines for treating EHL with treatment options are broad including: chemotherapy, ablation, surgery and liver transplantation with inconsistent results.