Interesting Cases from Liver Tumor Board Jeffrey C. Weinreb, M.D.,FACR Yale University School of Medicine jeffrey.weinreb@yale.edu
Common Liver Diseases Hemangioma Cyst FNH Focal Fat/Sparing THID Non-Cirrhotic Adenoma Metastasis Cirrhotic Fibrosis RN DN HCC Cholangioca
Nonalcoholic Fatty Liver Disease (NAFLD) Pathology resembles alcohol-induced liver injury Wide spectrum from simple steatosis, to steatohepatitis (NASH, CASH), advanced fibrosis, cirrhosis, and end-stage liver disease Frequently associated with obesity, type 2 diabetes, and hyperlipidemia Usually asymptomatic, but may have fatigue, malaise and sensation of discomfort Most common cause of abnormal LFTs among adults in USA
Pathology Triglyceride accumulation within hepatocytes Diffuse Fatty Liver CT Attenuation of liver is at least 10HU less that spleen or <40HU (on non- CE scans) Intrahepatic vessels may appear hyperattenuating c/w liver MR SI loss on opposed-phase images c/w in-phase images
Focal Fat Deposition May be round, geographic, or perivascular Characteristic locations adjacent to falciform lig or ligamentum venosum, in the porta hepatis, and in the GB fossa. Absence of mass effect on vessels and other structures Poorly delineated margins Contrast enhancement similar to or less than normal liver
45 yo f with abdominal pain and daily alcohol consumption Perivascular Fat Deposition CT MR In-phase Opposed-phase Radiology 2005;237:159-169
Cirrhosis Fibrosis Nodular regeneration Disturbed blood flow CT MR
Pseudocirrhosis Clinical In some patients receiving chemotherapy, a morphologic pattern develops similar to that associated with cirrhosis. Most common with breast cancer, but occurs with other cancers and lymphoma May occur with hepatotoxic drugs without liver metastases may be asymptomatic or may cause portal hypertension from venous compression Pathology Findings are suggestive of nodular regenerative hyperplasia which is characterized by the formation of regenerative hepatic nodules with compression and atrophy of parenchyma but without hepatic fibrosis. There may or may not be foci of residual tumor. It is thought to be a chemotherapeutic response due to shrinkage of tumor with subsequent scarring and nodular regeneration of uninvolved areas Imaging A lobular hepatic contour, segmental volume loss, and enlargement of the caudate lobe. Findings evolve over 1-3 months AJR 1994; 163:1385-1388
Cavernous Hemangioma Clinical Common; 7-20% of adults; female 5:1 MRI Very bright on T2WIs Enhancing nodules that become more numerous and confluent over time intensity Follows blood pool on all phases May not fill in
Peliosis Hepatis Pathology Rare benign disorder causing sinusoidal dilatation & presence of multiple blood filled lacunar spaces Usually a path (not imaging) diagnosis Clinical Associated with chronic wasting diseases,steroid medications, sprue, diabetes, vasculitis, hematological disorders Bacillary peliosis hepatis caused by Bartonella species in HIV-positive patients Complications: Liver failure/cholestasis/portal hypertension/liver rupture leading to shock
Peliosis Hepatis CT Findings NECT Multiple hepatic areas of low attenuation CT findings differ with size of lesions, presence or absence of thrombus within cavity & presence of hemorrhage CECT Larger cavities communicating with sinusoids have same attenuation as blood vessels Thrombosed cavities will have same appearance as nonenhancing nodules Arterial phase: Early globular vessel-like enhancement Multiple small accumulations of contrast, hyperdense in center or periphery of lesion Portal phase: Centrifugal or centripetal enhancement without mass effect on hepatic vessels Delayed phase: Late diffuse homogenous hyperattenuation characteristic of phlebectatic type
Peliosis Hepatis MR Findings T1WI Hypointense Signal due to presence of subacute blood suggestive of hemorrhagic necrosis T2WI Hyperintense Multiple foci of signal due to presence of subacute blood Post-C Lesions usually show contrast-enhancement Cystic cavity with enhancing rim representing hematoma Strong contrast-enhancement with "branching" appearance caused by vascular component
Focal Nodular Hyperplasia (FNH) Clinical Common; 2-5% of adults; female 4:1 Mostly young women with incidental mass No malignant potential MRI Looks almost like normal liver on non-c scans 13% multiple May be lobulated or have pseudocapsule (no true capsule) Never bleed, no Ca++ Rarely contain lipid Scar hypo on T1 and hyper on T2 Homogenously intensely enhances on HAP Homogenously washes out rapidly Delayed enhancement of scar Only approx 20% have classic features Persistant hyperintensity on delayed scans with Gd-BOPTA
Fibrolamellar Carcinoma (FLC) Pathology Diffuse fibrous stroma comprising fibrolamellar bands of collagen and fibrocytes arranged in a lamellar pattern and in delicate bands between nests of tumor cells Clinical Uncommon Primarily young adult (mean age 28) Not associated with hepatitis B virus, cirrhosis or metabolic abnormalities Usually normal serum markers Better prognosis than classic HCC; 5 year survival is 60% Imaging Findings Heterogeneously-enhancing, large, lobulated mass with hypointense central scar and radial septa on T2WI Size: Vary from 5-20 cm (mean 13 cm) Compared with FNH, FLC is bigger and more heterogeneous, frequently with calcified (68%) central/eccentric scar & features of malignancy (vessel/biliary obstruction, nodal & lung metastases)
Hepatic Masses FNH FLC Prevalence common rare Blood Products never rare Ca++ rare common Fat unusual never Central Scar common common Late Enhanced Scar common some Homogen Art Phase common never Homogen PV Phase common never
Ciliated Hepatic Foregut Cyst Pathology Derives from embryologic foregut Solitary, unilocular cyst made up of ciliated pseudostratified columnar epithelaium, a subepithelial layer of connective tissue layer, a smooth muscle layer, and an outer fibrous capsule Clinical Rare. Typically appears in 50 yo patients with male predominance Can show malignant transformation (extremely rare) Since it is the only cililated cyst that occurs in the liver, FNA is diagnostic Imaging Usually located in subcapsular location on the anterior aspect of the liver at the insertion of the falciform ligament (medial seg left lobe) May calcify Pathology Oncology Research 2002;8(4):278-279 BMC Cancer 2006, 6:244 Radiology 1990;175:475-477