Left Hepatic Lobe Research Articles

Hepatic Tumor as Antenatal Presentation of Costello Syndrome

A large hepatic mixed echoic mass occupying the left fetal abdomen was identified at 266/7 weeks. The mass showed peripheral and internal vascularity. Other ultrasound findings included edema of the fetal head and face, macrosomia, shortened long bones, abnormal posture of hands, small stomach, polyhydramnios and biventricular hypertrophy. Fetal magnetic resonance imaging confirmed a hypervascular mass replacing the lateral left hepatic lobe, suggestive of a congenital hemangioma. The fetus was delivered by cesarean section at 282/7 weeks. The baby was stabilized at day 3 of life, and underwent successful selective tumor embolization. The baby remained stable for 3 days, then deteriorated with a progressive thickening of the myocardium. The child then passed away on day 11 from severe progressive hypertrophic cardiomyopathy, with almost complete obliteration of the left ventricular cavity; an autopsy was declined. Postnatal investigations reported a de novo heterozygous pathogenic HRAS variant (NM_005343.3(HRAS): c.35_36 delinsTT, p.Gly21Val), previously reported in 8 cases associated with the early, lethal form of Costello syndrome.

Sample strategies for quantification of hepatic fat fraction mean MRI in healthy cats during body weight gain.

Hepatic fat fraction (HFF) can be non-invasively estimated with magnetic resonance imaging (MRI) multiple echo gradient recalled echo (GRE) sequence. The aim of this study was to test different methods of sampling strategies to quantify the HFF in healthy cats during body weight gain. Twelve healthy adult male cats were examined in a 3 Tesla MRI unit. Sequences included morphological images, and multiple echo GRE sequence. Cats were scanned at the beginning of the study and twice, each 20 weeks apart during body weight gain. HFF was calculated with 5 different methods of sampling on the multiple echo GRE sequence with different number, size and position of regions of interest (ROIs) and by 2 operators. Results indicated that HFF increased with increasing body weight, and the increase was appreciated with all the 5 methods. There was overall excellent agreement (interclass correlation coefficient = 0.820 (95% confidence interval:0.775–0.856)) between the 2 operators. HFF in the left lateral hepatic lobe was lower than in the other analyzed lobes. HFF measured on large free-hand drawn ROIs was higher than HFF measured with smaller ROIs size. This study proves that different sampling methods for quantification of HFF on multiple echo GRE sequence have overall excellent repeatability and ability to appreciate increased HFF.

Quatitative morphological analysis of the venous bed of the common bile duct in postresection portal hypertension

Introduction. Removal of the left and right lateral lobes of the liver in white rats leads to postresection portal hypertension, which is characterized by dilation and plethora of the hepatic portal vein, mesenteric veins, esophageal and gastric veins, veins of the anterior abdominal wall, splenomegaly, ascites.Objective of the research: to study the features of structural reorganization of the venous bed of the common bile duct in postresection portal hypertension morphometrically.Materials of the research and their discussion. The venous bed of the common bile duct was studied by morphometric methods in 32 laboratory white male rats, which were divided into 2 groups: 1-st group included 15 intact animals, 2-nd - 17 rats with postresection portal hypertension, which was modeled by removal of the left and right hepatic lobes. One month after the start of the experiment, rats were euthanized by bloodletting under conditions of thiopental anesthesia. Histological micropreparations were made from the common bile duct, on which the venous bed was mophometrically studied, the outer and inner diameters of veins, wall thickness, height of endotheliocytes, diameter of their nuclei, nuclear-cytoplasmic ratios in these cells, relative volume of damaged endothelial cells were measured. Quantitative indicators were processed statistically.Results of the research and their discussion. Morphometrically it was found that in postresection portal hypertension the outer and inner diameters of veins of the common bile duct markedly increased, their wall is thinned, the height of endothelial cells, the diameters of their nuclei decreased, the nuclear-cytoplasmic ratios in endotheliocytes were disturbed, the relative volume of damaged endothelial cells increased.Conclusions. Resection of the left and right lateral lobes of the liver in white rats leads to postresection portal hypertension and pronounced remodeling of the venous bed of the common bile duct, which was characterized by increase of outer and inner diameters of veins, thinning of their wall, decrease of height of endotheliocytes and diameters of their nuclei, violation of nuclear-cytoplasmic ratios in endothelial cells, increase of relative volume of damaged endothelial cells.

S3538 Needle Track Seeding in a Patient With Hepatocellular Carcinoma

INTRODUCTION: We present a case of a 56-year-old Caucasian male with a history of CAD, HTN, and HCV who initially presented in 3/2017 with lower extremity edema found to have newly diagnosed systolic heart failure and severe mitral regurgitation. During his workup for CABG and valve repair he was found to have cirrhosis secondary to HCV with hepatocellular carcinoma (HCC) by biopsy. After treatment for HCC the patient later developed recurrence due to needle track seeding. CASE DESCRIPTION/METHODS: After further imaging for his initial presentation of heart failure the patient underwent a CT guided fine needle aspiration and core needle biopsies of newly identified liver lesions in the left hepatic lobe (Figure 1). Pathology was consistent with HCC and the patient had no evidence of metastatic disease at that time. He was not deemed eligible for transplantation and was treated with transarterial chemoembolization (TACE). A surveillance MRI 7 months post-biopsy demonstrated a mass within the right rectus abdominus muscle which was located in the region of a prior biopsy tract (Figure 2). Given concerns for metastatic disease, the lesion was biopsied and histopathology was consistent with HCC. He was treated with cryoablation to the rectus abdominus muscle lesion and selective internal radiation therapy. The lesion was no longer visualized on follow-up imaging obtained four months later (Figure 3). DISCUSSION: Needle track seeding is a known complication with variable rates reported in the literature. More recent studies demonstrate a less than 1% rate of seeding when biopsy is performed alone.1,2 However, the rate is thought to be even lower in cases that use a coaxial biopsy system as was performed in this case. This is an important complication to consider as it may alter treatment; often disqualifying patients from liver transplantation or other curative procedures. For those who are being considered for liver transplantation diagnostic needle biopsies should be avoided if possible.Figure 1.: Axial contrast enhanced CT image in a 56 year old male showing CT guided percutaneous biopsy of a mass in the left hepatic lobe (circle).Figure 2.: Follow-up axial T1 post contrast MR images, 7 months later, showing a hyper-enhancing lesion in the right rectus abdominus muscle.Figure 3.: Axial T1 post contrast MR images of a 56-year-old male showing complete resolution of the soft tissue lesion following cryoablation. Residual tumor is noted in the left hepatic lobe.

S2426 Segmental Atrophy Associated With Overestimation of Fibrosis by Transient Elastography

INTRODUCTION: Hepatic atrophy, although rare, may be a potential confounder of transient elastography results. Atrophy can result from tumor or cirrhosis but can also be due to etiologies associated with diversion of portal venous blood flow. We present a case of overestimation of fibrosis by transient elastography in a patient with left hepatic lobe atrophy. CASE DESCRIPTION/METHODS: A 60 year old overweight male with hypertension and hyperlipidemia was referred for evaluation of elevated transaminases. Initial laboratory investigation noted AST 62 U/L, ALT 110 U/L, alkaline phosphatase (ALP) 160 U/L, total bilirubin 0.7 mg/dL, platelet count 172,000/microliter and albumin 4.2 g/dL. He was advised to stop taking high intensity atorvastatin and abstain from alcohol consumption, though alcohol intake was one glass of wine nightly. Repeat testing demonstrated AST 39 U/L, ALT 58 U/L, ALP 98 U/L and total bilirubin 0.9mg/dL. An abdominal ultrasound was obtained and showed cavernous transformation of the portal vein (PV) with gastrosplenic varices. Computed tomography of the abdomen (Image 1) confirmed these findings and also revealed atrophy of the left hepatic lobe. The etiology of chronic PV thrombus was explored. Protein C and S, and antithrombin III were within reference range. Anticardiolipin antibody was negative. JAK2 and Factor V Leiden mutations were negative. Given risk factors for non-alcoholic fatty liver disease, we decided to evaluate the extent of fibrosis with transient elastography during the patient's office visit. FibroScan measured liver stiffness at 21.1 kPa, correlating with F4 fibrosis. No overt confounders were identified. To confirm the diagnosis of cirrhosis, the patient underwent a percutaneous liver biopsy. The sample obtained was from the right liver lobe and was adequate for interpretation, over 2cm in length. It showed minimal macrovesicular steatosis without features of steatohepatitis and no significant portal or lobular inflammation. Trichrome stain revealed stage 1 fibrosis with patchy perisinusoidal fibrosis. DISCUSSION: We concluded that the patient did not have cirrhosis, and that chronic PV thrombus contributed to left hepatic lobe atrophy. The etiology of chronic PV thrombus remains elusive. FibroScan results were likely confounded by the atrophic left hepatic lobe. Our case highlights the importance of confirming cirrhosis with liver biopsy in particular subsets of patients given the many implications in the patient’s monitoring and prognosis with a diagnosis of cirrhosis.Image 1.: Atrophy of the Left Hepatic Lobe.

S2419 Recurrent Oriental Cholangiohepatitis

INTRODUCTION: Recurrent cholangiohepatitis was first recognized as a clinical entity in the 1930s and is most commonly found in people of Southeast Asian origin. We present a case of recurrent pyogenic cholangiohepatitis with hepatic abscess in a patient of oriental origin. CASE DESCRIPTION/METHODS: 58 y/o male with medical history of hypertension who was admitted with 4 days of fevers and RUQ abdominal pain. He was hypotensive with leukocytosis and elevated lactate. He had a history of Choledochoduodenostomy, done in Korea, due to primary intrahepatic choledocholithiasis. CT A&P showed left hepatic lobe mass containing dilated fluid-filled structures, left hepatic lobe atrophy, and pneumobilia and broad spectrum antibiotics were initiated. IR guided drainage of liver lesion was performed and catheter tube was placed. Fluid drained grew E. Coli and VRE. AFP, CEA, and CA 19-9 were negative. Stool negative for O&P. MRCP showed intrahepatic ductal dilatation of the left hepatic lobe and central intrahepatic ductal dilatation in the right hepatic lobe. EUS showed hepatic abscess and a gastrohepatic lymph node was biopsied, which showed reactive lymphoid tissue and no malignant cells. ERCP was done, but strictures in left intrahepatic bile ducts were not amenable for stent placement and drainage. PTC was performed and internal biliary drainage catheter was placed. Diagnosis of Oriental Cholangiohepatitis was made. Patient was offered left liver lobectomy for definitive treatment, he deferred. He clinically improved and was discharged. DISCUSSION: Oriental Cholangiohepatitis is characterized by recurrent cholangitis secondary to bile stasis and stone formation proximal to biliary strictures. Left hepatic duct, especially the left lateral segmental duct, is most commonly affected. Pneumobilia and hepatic atrophy are common findings on imaging. Intrahepatic calculi are visualized in up to 90% cases. Management includes antibiotic therapy, stricture dilation, biliary drainage, stone removal and liver resection. ERCP has advantage of therapeutic intervention over MRCP. Liver resection decreases the risk of recurrent attacks of cholangitis, abscess and eliminates the risk of carcinoma in the atrophic segment of liver. Incidence of oriental cholangiohepatitis is increasing in the western world due to immigration and diagnosis should be considered in patients in epidemiologic and clinical settings, with radiologic findings of intrahepatic ductal dilation even in the absence of visualization of intrahepatic stones.

S2564 Cyanoacrylate Embolization Following EGD Resulting in Fulminant Hepatic Failure in a Patient With Cirrhosis

INTRODUCTION: Esophagogastric varices are a common complication of portal hypertension and can present with life-threatening bleeding. Definitive endoscopic therapy is via band ligation or sclerotherapy. The former is preferred for esophageal varices, but efficacy is lower in gastric varices (GV). Sclerotherapy with cyanoacrylate (CA) has shown better efficacy and is now recommended as first line therapy for bleeding GV. Studies on long-term efficacy and complications remain limited. CASE DESCRIPTION/METHODS: A 62-year-old woman with NASH cirrhosis (MELD 11) presented with hematemesis. She denied any history of SBP, varices, or encephalopathy. She endorsed a previous history of COVID-19 and had reactive IgG but PCR probe for SARS-CoV-2 was negative. She underwent EGD and was found to have oozing GV along the lesser curvature, which were treated with 4cc of CA achieving hemostasis. The following night she had altered mentation and the blood lactate was increased to 7.2 mmol/L. AST and ALT were also increased. She received broad spectrum antibiotics, and a CT angiogram showed evidence of embolization of CA into the left lobe of the liver. On day 3 her level of consciousness declined and she was intubated for airway compromise. An MRCP confirmed the presence of CA within the left hepatic lobe with associated ischemia. The lactate increased to 20 mmol/L and the blood ammonia level to 700 mcg/dL, with MELD 45. Continuous hemodialysis was started for anuric renal failure. She underwent evaluation for liver transplantation, but cerebral edema and multiorgan failure with refractory acidosis occurred and she died on day 7. DISCUSSION: We present a case of GV treated with CA and the subsequent embolization of CA into the left lobe of the liver. This precipitated acute on chronic liver failure with features of fulminant hepatic failure (FHF) complicated by severe hyperammonemia, cerebral edema, multiorgan failure, and death. Although she had a recent diagnosis of COVID-19, the time course, relatively normal initial inflammatory markers, and imaging suggest that CA embolization was likely the injury that led to fulminant hepatic failure. Given the lack of case reports of CA embolization to the liver causing infarction and few cases to the brain or distant vessels, further research on its long-term safety is warranted. Another novel aspect to this case is the development of FHF in a patient with known cirrhosis.

S1857 EUS-Guided Fine Needle Core Liver Biopsy With a Modified 1-Pass 1-Actuation Wet Suction in Non-Alcoholic Fatty Liver Disease

INTRODUCTION: Liver biopsy is currently the benchmark in the assessment of hepatic disease, particularly in visualizing the histologic degree of fibrosis. However, the invasive nature of traditional sampling methods can pose danger to the patient. The emergence of EUS-guided liver biopsy (EUS-LB) provides the endoscopist the option to offer a treatment modality with advantages such as reduced pain, increased safety due to continuous ultrasound guidance, the ability to take multiple samples with a widened view of the organ, and can be performed in the outpatient setting. CASE DESCRIPTION/METHODS: A 56-year old female with multiple co-morbidities such as obesity, hypertension and diabetes mellitus type 2 presented with right upper abdominal discomfort and worsening fatigue. She denies alcohol use. Physical examination displayed mild hepatomegaly with some tenderness to palpation. AST and ALT levels were moderately elevated. In conjunction with the patient presentation, elevated LFT’s and radiographic findings, nonalcoholic fatty liver disease (NAFLD) was suspected. EUS-guided liver biopsy was selected for this patient. A linear EUS endoscope is advanced into the duodenum at the location of the duodenal bulb. In this position, the left hepatic lobe is located from the proximal stomach or right hepatic lobe. First, open the 19-gauge needle and remove the stylit. After, flush the needle with normal saline. Then, a needle trajectory of approximately 5 cm is chosen, avoiding large vessels. The needle travels through the duodenal wall and into the liver and one pass is made through liver tissue. Withdraw the needle as saline is placed into the syringe at 20 cc suction. Suction is stopped once the sample is obtained. Once the specimen has been collected, it is directly placed into formalin from the needle. DISCUSSION: We have shown the efficacy of EUS-MLB. It has been shown to accurately predict fibrosis in patients with fatty liver disease and several studies cite a range of diagnostic yields ranging from 91 to 100%. However, some potential pitfalls include the similar visual nature of the liver and spleen on EUS, a misidentified spleen can result in an adverse bleeding complication. Additionally, tissue sample yield can be dependent on the endoscopist’s technical skill with this complex procedure.Figure 1.: EUS displaying increased areas of hepatic echogenicity suggestive of NAFLD.Figure 2.: 19-gauge needle advancing through the liver using one pass to obtain optimal viable tissue sample.Figure 3.: Live view of parenchymal tissue obtained via EUS.

S2741 Entamoeba Histolytica Dysentery Complicated by Amebic Liver Abscess and Type a Right Heart Thrombus: A Case Report

INTRODUCTION: This is a unique case of invasive amebiasis complicated by a right atrial thrombus in a healthy immigrant. CASE DESCRIPTION/METHODS: A 35 y/o man without past medical history presented with a two-week history of fever, night sweats, anorexia and malaise. He had one week of bloody diarrhea that resolved. He immigrated to the USA 11 years prior from Myanmar. On presentation he met SIRS criteria with unremarkable abdominal exam. CT showed a single rim enhancing lesion in the hepatic dome along with ascending colonic wall thickening with perifat-stranding and a filling defect in the IVC with extension into the right atrium. His transthoracic cardiac echo revealed a large, mobile thrombus in the right atrium. Biopsy of the hepatic abscess confirmed E. Histolytica infection. Further inherited hypercoagulability work up was negative.He did well post discharge on oral antibiotic therapy and anticoagulation. DISCUSSION: The standard for diagnosis of intestinal infection is by stool PCR. Extraintestinal disease is diagnosed by serum antigen testing with high sensitivity (>94%) and specificity (>95%). False negatives can be seen early in the disease. Management of amebiasis depends on the extent of disease. A luminal agent, like paromycin, is sufficient to eliminate intraluminal cysts in non-invasive colitis and asymptomatic carriers. For invasive amebiasis and extra intestinal disease metronidazole is the mainstay of treatment. This should always be followed by a luminal agent to prevent relapse as metronidazole is not effective against cysts. Indications for amebic liver abscess drainage includes persistence of clinical symptoms, presence in the left hepatic lobe, large size with imminence of rupture in the right lobe, pregnant patients or pulmonary complications. The current proposed mechanism for the development of a right atrial thrombus is that extra-intestinal amebiasis triggers a local pro-thrombotic state that leads to hepatic vein thrombus development that may extend into the IVC and eventually the right atrium. There is no consensus on management of right atrial thrombi due to the rare occurrence and lack of randomized controlled trials. Widely recognized treatment options are surgical thrombectomy, thrombolysis, percutaneous interventional techniques, and systemic anticoagulation. The mortality in patients with a mobile right atrial thrombus is 19–45% emphasizing the importance for clinicians to consider this diagnosis in patients with invasive amebiasis in the appropriate clinical setting.Figure 1Figure 2Figure 3.: E. Histolytica life cycle.

S2729 Not Your Typical Polyp: An Unusual Case of HCC Recurrence Following OLT

INTRODUCTION: OLT is a viable treatment option for select patients with ESLD and HCC. However, post-transplant recurrence of HCC occurs in approximately 20% of patients. Risk factors include explant tumor burden exceeding Milan criteria, lymphovascular invasion, and elevated pre-transplant AFP levels. The most common locations of metastatic HCC include the lungs, bones, and adrenal glands. We report an unusual case of HCC recurrence to the colon detected during colonoscopy. CASE DESCRIPTION/METHODS: A 69-year-old Caucasian male with a history of EtOH/NASH cirrhosis on the liver transplant list underwent routine abdominal imaging, which revealed a 2.0 × 1.7 cm liver mass compatible with HCC. AFP was within normal limits and there was no evidence of pulmonary metastasis. He underwent TACE and microwave ablation of 4 identified lesions. Follow-up multiphasic liver CT imaging at 1 and 3 months were negative. Patient subsequently underwent OLT 6 months after locoregional therapy. Explant pathology revealed 4 sites compatible with treated HCC in the left hepatic lobe with explant tumor burden within Milan criteria. Areas of incomplete necrosis showed well-differentiated HCC without any evidence of lymphovascular invasion.Patient’s post-OLT course was initially uncomplicated. Imaging at 1 year post-transplant demonstrated enlarging necrotic paraesophageal and gastroesophageal lymph nodes as well as focal circumferential ascending colonic wall thickening. Patient subsequently underwent endoscopy with EUS and FNA of the paraesophageal lymph node. Colonoscopy revealed a 20 mm hepatic flexure polyp, which was removed via piecemeal cold-snare EMR. Pathology of the paraesophageal lymph node and hepatic flexure polyp were consistent with metastatic HCC. Following tumor board discussion, patient was initiated on first-line systemic therapy. He continues to follow up in transplant clinic. DISCUSSION: To our knowledge, this is the first reported case of HCC metastasis to the colon presenting as a polypoid mucosal lesion. Despite having a low risk of recurrent HCC based on pre-transplant and explant tumor characteristics, our patient’s unusual presentation occurred at 1-year post-transplant. While the diagnosis of recurrent or metastatic HCC confers a guarded prognosis, there are an increasing number of options for systemic therapies. Clinicians should adopt a low threshold for further evaluation of abnormal imaging findings in this context to enable early detection of recurrent post-transplant HCC.Figure 1.: CT 6 months (left) and 12 months (right) post OLT demonstrating enlarging paraesophageal lymph node.Figure 2.: 20 mm hepatic flexure polyp removed via piece-meal cold snare EMR.Figure 3.: Pathology of paraesophageal lymph node (left) and hepatic flexure polyp (right) consistent with metastatic HCC.

S3057 Upper Gastrointestinal Bleeding Secondary to Gastric Metastasis of Pleomorphic Dermal Sarcoma

INTRODUCTION: Pleomorphic dermal sarcoma (PDS) is a rare cutaneous malignancy, seen primarily in sun exposed areas of elderly individuals. Along with atypical fibroxanthoma (AFX), it is believed to belong to a spectrum of malignant disorders arising from a similar fibrohistiocytic mesenchymal origin. Compared to AFX, PDS represents a more aggressive phenotype of disease with higher rates of recurrence and metastasis. CASE DESCRIPTION/METHODS: An 87-year-old male with a history PDS of the scalp with metastasis to the right humerus presented to the hospital with one week of melena. Pertinent past medical history included non-small cell lung cancer, chronic lymphocytic leukemia, melanoma, squamous and basal cell carcinoma of the skin. On presentation he was noted to be anemic with a hemoglobin of 6.8 g/dL and hematocrit of 22%. He was started on intravenous (IV) proton pump inhibitor (PPI) and underwent an esophagogastroduodenoscopy (EGD). Upon visualization of the stomach, four masses were identified along the greater curvature ranging between 1cm and 2.5cm in size, three of which were actively bleeding. Biopsies of these masses were obtained with cold biopsy forceps. No alternative source of bleeding was identified on exam. Following EGD, supportive measures were continued with IV PPI and packed RBC transfusions. Tissue histology of the gastric masses were consistent with a malignant spindle cell neoplasm, identical to that of the patient's known PDS. Additional imaging revealed new soft tissue lesions in the left hepatic lobe, right kidney, bladder and peritoneum. Given his diffusely metastatic disease, co-morbidities and frailty, therapeutic options were limited. He was deemed not an appropriate chemotherapy candidate and ultimately pursued hospice care. DISCUSSION: We present a case of upper gastrointestinal bleeding secondary to gastric metastasis of PDS. Metastasis occurs in approximately 10-20% of patients with PDS, most commonly involving the lungs and skin1. PDS had previously been classified as undifferentiated pleomorphic sarcoma or malignant fibrous histiocytoma. Under this nomenclature it has rarely been described to metastasize to the stomach and few cases have presented with gastrointestinal bleeding. This case contributes to the general understanding that the stomach can be a metastatic site for a wide variety of non-gastrointestinal cancers.Figure 1.: Proximal gastric body mass along the greater curvature.Figure 2.: Distal gastric body mass along the greater curvature.

Development of Ectopic Livers by Hepatocyte Transplantation Into Swine Lymph Nodes.

Orthotopic liver transplantation continues to be the only effective therapy for patients with end‐stage liver disease. Unfortunately, many of these patients are not considered transplant candidates, lacking effective therapeutic options that would address both the irreversible progression of their hepatic failure and the control of their portal hypertension. In this prospective study, a swine model was exploited to induce subacute liver failure. Autologous hepatocytes, isolated from the left hepatic lobe, were transplanted into the mesenteric lymph nodes (LNs) by direct cell injection. At 30‐60 days after transplantation, hepatocyte engraftment in LNs was successfully identified in all transplanted animals with the degree of ectopic liver mass detected being proportional to the induced native liver injury. These ectopic livers developed within the LNs showed remarkable histologic features of swine hepatic lobules, including the formation of sinusoids and bile ducts. On the basis of our previous tyrosinemic mouse model and the present pig models of induced subacute liver failure, the generation of auxiliary liver tissue using the LNs as hepatocyte engraftment sites represents a potential therapeutic approach to supplement declining hepatic function in the treatment of liver disease.

S2466 Homomorphic Adenocarcinoma Metastases to the Liver: A Report of Two Cases

INTRODUCTION: Classifying a malignant lesion as primary or metastatic can be challenging in some cases. However, identifying the underlying primary disease is crucial for guiding therapy. We describe two cases of liver lesions of unclear etiology that were ultimately determined to be from metastatic adenocarcinoma originating in the ampulla (Case 1) and the colon (Case 2) and were curiously “homomorphic” in appearance. That is, their radiographic appearances resembled a dilated tubular structure akin to the ampulla and a haustrated bowel akin to the colon, respectively. Tumor homomorphism is a relatively new concept utilizing visual similarities to aid in determining an uncertain primary source of metastatic disease. CASE DESCRIPTION/METHODS: Case 1: A 51-year-old male who presented with dyspnea and right upper quadrant abdominal pain underwent computed tomography (CT) of the abdomen, revealing a solitary, 6 cm, cystic lesion in the liver, reminiscent of an ampulla anatomically (Figure 1). Percutaneous biopsy showed adenocarcinoma with signet-ring features of unknown primary. An obstructive mass was seen by endoscopy in the region of the major duodenal papilla. Endoscopic biopsy confirmed tumor cells with signet ring features and a mucinous background (Figure 2). Immunohistochemical evaluation was positive for BerEP4, consistent with signet-ring adenocarcinoma. Case 2: A 46-year-old male presented with five months of generalized abdominal pain, weight loss, constipation, and recent vomiting. CT of the abdomen and pelvis demonstrated numerous hypodense liver lesions. Percutaneous biopsy of the liver lesions revealed malignant glands positive for CK20 and CDX2 and negative for CK7, consistent with intestinal-type adenocarcinoma, suggestive of colorectal primary. On further review of the CT images, annular thickening of the rectosigmoid junction was noted, and the liver lesions were reminiscent of colon, being capacious with haustra-like septations (Figure 3). Colonoscopy revealed a firm, malignant appearing lesion at the rectosigmoid junction. DISCUSSION: The liver is a common site of tumor metastasis. While numerous diagnostic modalities can help detect the primary malignancy, they are often costly, time-consuming, invasive, and may still be inconclusive. Hence, as recently reported in hollow viscous organs and as illustrated here in the context of the liver, the presence of tumor homomorphism may allow clinicians to visually link a metastatic lesion to its primary source, thus providing a unique diagnostic clue.Figure 1.: Computed tomography (CT) scan depicting a 6 cm, ampulla-like, cystic appearing hypodense left hepatic lobe lesion with bile duct and periampullary thickening resulting in mass effect and consequent duodenal stenosis.Figure 2.: Ancillary studies on cytology specimen illustrating malignant cells with signet ring features.Figure 3.: Computed tomography (CT) scan of the abdomen and pelvis illustrating liver metastasis reminiscent of a sigmoid colon anatomically delineating the concept of homomorphism.

S1600 Intraductal Papillary Neoplasm of the Left Hepatic Duct Treated With Endoscopic Retrograde Cholangiopancreatography (ERCP)-Guided Radiofrequency Ablation

INTRODUCTION: Intraductal papillary neoplasm of the biliary tree (IPNB) is a rare tumor that can occur anywhere along the biliary tract. Treatment has traditionally relied on modalities including surgery and stenting. Recently, radiofrequency ablation (RFA) has gained momentum as a treatment option for biliary cancers. Prior studies examining the effect of RFA on biliary tumors typically group all tumors together, leaving few reports looking at sole outcomes in IPNB. CASE DESCRIPTION/METHODS: An 87-year-old woman with arthritis, GERD, dementia, and HTN presented to the ED with a one day history of nausea, vomiting and RUQ abdominal pain. Laboratory examination revealed a total bilirubin of 2.7, ALP 189, AST 401, ALT 294, CA 19-9 156, CEA 3.4, and AFP 3.58. MRCP showed a 21 mm × 31 mm non-infiltrating lesion within the left hepatic duct extending to the confluence of the common hepatic duct with extensive biliary ductal dilation of the left hepatic lobe (Figure 1). ERCP showed a high grade stricture extending from the hilum to the left hepatic duct. On cholangioscopy, a polypoid mass was noted in the left hepatic duct (Figure 2). Multiple biopsies were obtained which were diagnostic of IPNB. A 10 Fr x 12 cm double pigtail biliary stent was placed in the left ductal system. Given her advanced age and dementia, the patient was thought to be a poor surgical candidate and a decision was made to treat her with RFA. She subsequently underwent 3 ERCP’s with ablation of IPNB located in the left hepatic duct using a Habib EndoHPB ablation catheter without complications. A follow-up MRI 1 year post-diagnosis showed improvement and regression of the left intrahepatic intraductal mass to 9.6 mm × 10.6 mm (Figure 3) and decompression of the left intrahepatic biliary tree. Repeat CA 19-9 improved to 8.24. DISCUSSION: To the best of our knowledge, this is the first case report of ERCP guided RFA of an intrahepatic IPNB. Our case highlights the use of RFA in combination with biliary stenting as a primary therapy for IPNB in patients who are poor surgical candidates.Figure 1.: Abdominal MRI with a 21 mm × 31 mm lesion in the left hepatic duct.Figure 2.: Polypoid mass seen on cholangioscopy in the left hepatic duct.Figure 3.: Abdominal MRI with decrease in size of intrahepatic IPNB (9.6 mm × 10.6 mm) post-RFA.

S2508 Primary Hepatic Angiosarcoma Presenting as Decompensated Cirrhosis

INTRODUCTION: Angiosarcomas are uncommon and aggressive endothelial cell tumors which arise from vessels or lymphatic tissue. The common sites are the head, neck, extremities and breast. It can spread hematogenously to lung, liver, lymph nodes, bones and rarely bowel (Lancet oncol 2010; 11:984). Primary hepatic angiosarcoma (HAS) is a rare and aggressive soft tissue tumor with dismal outcome. The known etiologies include exposure to vinyl chloride monomers, thorium oxide, arsenic, anabolic steroids, history of neurofibromatosis and hemochromatosis. CASE DESCRIPTION/METHODS: An 83-year-old male with a history of myasthenia gravis presented with abdominal distention, peripheral edema and intermittent encephalopathy for one month. Myasthenia gravis was treated with prednisone and azathioprine. Labs showed anemia, thrombocytopenia and elevated transaminases (ALT 33, AST 66, ALP 82, total bilirubin 0.7), INR was 1.2. Further testing for viral hepatitis and autoimmune panel were negative. A CT abdomen showed a nodular liver, ascites, innumerable hypoattenuating liver masses with a peripherally enhancing lesion (2.8 cm) and a hyper-vascular 2 cm mass in the right lobe. The head neck and chest imaging were negative for primary malignancy or metastatic disease. Ascites fluid analysis was consistent with portal hypertension. The liver biopsy suggested primary hepatic angiosarcoma which was confirmed on immunohistochemical staining. The patient decided not to opt for treatment and hospice was initiated. DISCUSSION: The only known risk factors in our case were advanced age and concurrent use of immunosuppressive agents. There is no specific tumor marker and a British study had shown negative alpha feto-protein for all the angiosarcoma cases (Gut 1987; 28:669). On immunohistochemistry the tumor cells express CD31, CD34, von Willebrand factor, vascular endothelial growth factor, and Ulex europaeus agglutinin 1. HAS manifests clinically at an advanced stage and life expectancy is usually 6 months. The (AASLD) considers angiosarcoma as a contraindication to liver transplantation (Hepatology 2014; 59:1147). Tumor resection is favorable only in subjects with a solitary tumor involving one hepatic lobe. Chemotherapy or locoregional therapy in surgically non-resectable tumors has shown no survival benefit. Hepatic angiosarcoma can develop in elderly, immunosuppressed individual. It can present as incidental hepatic mass or decompensated liver disease. Liver biopsy with immunohistochemical staining is the best diagnostic test.Figure 1.: CT abdomen axial section showing peripherally enhancing mass (red arrow) in right hepatic lobe.Figure 2.: CT abdomen axial section showing right hepatic lobe hypervascular lesion (red arrow) and diffuse hypoattenuating lesions.Figure 3a.: Liver biopsy Hematoxylin-eosin (H&E) staining stain of left hepatic lobe showing endothelial cells with enlarged hyperchromatic nuclei lining the vascular channels; 3b: Immunohistochemical stain shows that the tumor cells are positive for vascular antigen CD34.

S3328 An Unfortunate Case of Synchronicity

INTRODUCTION: Gastrointestinal stromal tumors (GISTs) account for less than 1% of GI tumors. They originate from the interstitial cells of Cajal and are the most common group of mesenchymal neoplasms. GISTs may occur in any portion of the alimentary tract. Recent literature suggests that GISTs may occur synchronously with other cancers more frequently than expected. CASE DESCRIPTION/METHODS: We present a case of a 78-year-old female with past medical history of hyperlipidemia who underwent an outpatient computed tomography (CT) for evaluation of abdominal pain. CT scan revealed three lesions: (1) 7.2 cm well-circumscribed hypodense hepatic lesion in segment 7 consistent with hydatid cyst (Figure 1a), (2) 3.6 cm ill-margined heterogeneous lesion of uncinate process (Figure 1a), and (3) 5.1 cm partially cystic intramural gastric body mass with exophytic extension (Figure 1b). The patient underwent esophagogastroduodenoscopy (EGD) and endoscopic ultrasonography (EUS). No intraluminal component of gastric mass was visualized on EGD. A 26.5 × 21.6 mm hypoechoic, heterogeneous and well-circumscribed lesion with several anechoic components was identified adjacent to gastric cardia on EUS. Fine needle biopsy (FNB) was performed with pathology revealing spindle cell tumor (Figure 2) and immunohistochemical staining consistent with GIST (CD 117 positive, S100 negative and SMA focally positive). Additionally, a 21.7 × 21.6 mm heterogeneous hypoechoic lesion with ill-defined borders was identified in an uncinate process. FNB was performed (Figure 3a) with pathology revealing adenocarcinoma (Figure 3b). Finally, a large hepatic lesion with multiple anechoic components surrounded by hyperechoic rims with acoustic shadowing was identified in the left lobe. DISCUSSION: Our case presents a rare finding of synchronous gastric GIST and pancreatic adenocarcinoma. The percentage of GIST occurring with other neoplasms is reported to range between 3% and 33%. There is no recognized pattern to ascertain whether the coexistence of these tumors is incidental or related to a genetic or pathologic process. The etiology of synchronous occurrence of GISTs with histologically unrelated tumors remains unclear, however, some authors have suggested that they may share common genetic mutations with proliferation of different cell lines. As there is a limited number of cases, future studies are needed to evaluate this link, but it is important for both pathologists and surgeons to be aware that this phenomenon does exist.Figure 1.: (a) CT scan with pancreatic head mass and left hepatic lobe lesion; (b) CT scan with proximal gastric mass.Figure 2.: Pathology slide displaying spindle cells obtained from FNB of gastric mass.Figure 3.: (a) EUS image showing FNB of pancreatic mass; (b) Pathology slide displaying malignant adenocarcinoma.

Multiple septae as potential protective factors against spontaneous pyogenic liver abscess rupture: a propensity score matching analysis.

The symptoms of spontaneous rupture of a pyogenic liver abscess (PLA) are severe and often life-threatening. Multiple septae are important imaging features of PLA. However, the relationship between septation and abscess rupture is still under debate. Patients diagnosed with PLA from January 2011 to November 2019 in our hospital were included. We collected demographic, clinical, and computed tomography data. Univariate and multivariate analyses determined liver abscess rupture risk factors. The relationship between multiple septae and abscess rupture was evaluated by propensity score matching after matching other influencing factors. A total of 583 patients of pyogenic liver abscesses were included in the study: 30 ruptured and 553 unruptured. Multivariate analysis revealed diabetes, single lesion, gas formation, left hepatic lobe location, and a diameter > 66.5mm as independent risk factors for ruptures, while multiple septae were identified as a protective factor. After matching all the influencing factors (excluding multiple septae), multiple septae and abscess rupture maintain a negative relationship. Multiple septae were identified as a potentially protective factor against spontaneous pyogenic liver abscess ruptures.

Ectopic Gallbladder: An Incidental Finding

Ectopic gallbladder is a rare entity with an incidence of 0.1%- 0.7% [1]. Normally, it lies on the gallbladder fossa, on the inferior surface of the liver in between the right and left hepatic lobes, maintaining a constant relationship to porta hepatis [2]. On Ultrasonographic imaging, the gallbladder can be identified by the relationship of the gallbladder neck anterior to the right branch of the portal vein. Ectopic gallbladder can be located in various positions such as intrahepatic, within the lesser omentum, retroduodenal, within falciform ligament, abdominal wall muscles and in thoracic cavity [3, 4]. An ectopic gallbladder is a dangerous entity as it can lead to misdiagnosis. We were presented a case of ectopic gallbladder, which was missed in ultrasound, and CT scan report but was discovered intra operatively during laparoscopic cholecystectomy

MM-021: Case Report: Successful Management of Hepatic Lesions Secondary to Multiple Myeloma (MM) with Lenalidomide and Dexamethasone

A 43-year-old male with severe back pain was diagnosed in 2011 with IgA kappa multiple myeloma associated with multiple lytic bone lesions (costal and pelvic lesions). The bone marrow biopsy was consistent with MM. The immunohistochemistry study showed CD38+ and kappa+. Induction chemotherapy with bortezomib 1.3 mg/m² thalidomide 200 mg, steroids 40 mg and zoledronic acid 4 mg IV was initiated with a very good response. He underwent ASCT after he was maintained on thalidomide, dexamethasone, and zoledronic acid. In September 2018, the patient complained of right lower limb pain. Lumbar MRI demonstrated an isolated bone mass at the L3-L4 level. Bone marrow aspiration and biopsy with protein electrophoresis and immunofixation were performed confirming disease relapse. The level of plasma cells in the bone marrow was <3%. The serum protein electrophoresis was normal. Surgical resection of the lumbar mass was done. The histological report showed a plasma cell neoplasm. Surgery was followed with 30 sessions of radiotherapy. In March 2019, the patient presented with severe right upper quadrant for which an abdominal CT scan showed a hypermetabolic mass in the liver. Lab tests showed CEA 1.68 ng/ml and CA19.9 16.44 U/ml with a suspicion of colon cancer. PET CT scan showed hypermetabolic mass on the segment IV of the liver, and in the left hepatic lobe. MRI of the abdomen March 2019 revealed multiple metastatic hepatic deposits. Biopsy of one of the hepatic lesions showed diffuse infiltrate of atypical plasmacytoid cells with prominent nucleoli and numerous mitoses on macroscopic evaluation while immunohistochemistry demonstrated positive staining for CD138, kappa light chain restriction, scattered small CD3-positive T cells, and CD20-positive B cells, thus confirming a new relapse of his multiple myeloma. Myelogram with flow cytometry in March 2019 with no plasmocytes. After a thorough discussion with the patient, daratumumab was not initiated due to financial reasons, which incited the start of second line treatment with lenalidomide 25 mg, dexamethasone 40 mg, and zoledronic acid 4 mg. A subsequent evaluation of response by PET CT scan performed 4 months after the initiation of therapy showed a complete disappearance of myeloma-related hepatic lesions.

Phantom simulation of liver metastasis on a positron emission tomography with computed tomography scan after neoadjuvant chemoradiotherapy for distal esophageal cancer: a case report

BackgroundNeoadjuvant chemoradiotherapy is currently the gold standard treatment for esophageal cancer prior to surgery. This radiation therapy will sometimes lead to liver damage parallel to esophageal lesions, which mimics liver metastasis visualized by 18F-fluorodeoxyglucose positron emission tomography with computed tomography. In this report, we publish virtual radiation-induced liver damage images obtained during surgery, along with the coherent pathology, in order to confirm the false-positive result through an optimally decisive radiological examination.Case presentationWe report a case of a Asian male patient with distal esophageal cancer who had undergone neoadjuvant chemoradiotherapy (5000 cGy). Subsequently, a new lesion was discovered during a positron emission tomography with computed tomography scan 6 weeks later, near the left caudate lobe of the liver during tumor restaging. To exclude the possibility of liver metastasis, serial imaging was conducted, which included liver sonography, computed tomography, and magnetic resonance imaging for a more intimate probe. The patient’s condition was verified as being liver inflammation change, as seen by the liver magnetic resonance imaging presentation. Thoracoscopic esophagectomy was performed with cervical esophagogastrostomy via the retrosternal route, along with a feeding jejunostomy. The procedure was performed smoothly, with an intraoperative liver biopsy also being conducted 2 weeks later, after positron emission tomography with computed tomography restaging. The pathology report revealed esophageal cancer in the form of poorly differentiated squamous cell carcinoma, pT3N1M0. The liver biopsy revealed obvious inflammation change after radiation therapy, which elucidated sinusoidal congestion with the attenuated hepatic cords and filled with erythrocytes. There was no evidence of liver metastasis. The patient recovered uneventfully and was discharged with his oral intake performing smoothly, and a stable condition was observed during 12 months of outpatient department follow-up.ConclusionsNew foci of increased 18F-fluorodeoxyglucose avidity are commonly seen in the caudate and left hepatic lobes of the liver during neoadjuvant chemoradiation for distal esophageal cancer, and these findings generally reflect radiation-induced liver disease rather than metastatic disease. Awareness of the pitfalls of a high 18F-fluorodeoxyglucose uptake in radiation-induced liver injury is crucial in order to avoid misinterpretation and overstaging. Except for the location of 18F-fluorodeoxyglucose uptake, the shape of the lesion, and an maximum standardized uptake value (> 10/h), a convincing liver magnetic resonance imaging scan or even a liver biopsy can provide accurate information for distinguishing radiotherapy-induced liver injury from liver metastasis.