FOCAL HEPATIC LESIONS IMAGING DIAGNOSIS 5th ARAB RADIOLOGY CONGRESS 25th - 28th April 2012 FOCAL HEPATIC LESIONS IMAGING DIAGNOSIS W.MNARI, M. GOLLI MONASTIR-TUNISIA

Objective : Identify the most important imaging features of common benign liver tumors Identify the most important imaging features of malignant lesions Know the diagnosis of hepatocellular carcinoma

Introduction Extensive use of imaging studies has increased the detection rates of hepatic lesions A mass can be found either incidentally or during screening for liver cancer in patients with cirrhosis These can be benignant or malignant and thus the right approach for assessing these masses is important

Classification: Benign Malignant Hemangioma Focal nodular hyperplasia Adenoma Liver cysts … Primary liver cancers Hepatocellular carcinoma Fibrolamellar carcinoma Cholangiocarcinoma Metastases

Things to consider usually..... Symptomatic or Incidentally detected History of Hepatitis or extra hepatic malignant tumor Liver function tests Cirrhotic or Non cirrhotic

Circumstances of discovery Fortuitous Non cirrhotic Symptomatic Non cirrhotic Chronic disease Cirrhosis Benign Malignant Hémangioma FNH Adénoma Metastasis FLC HCC DN RN

Benign Liver Lesions

Hepatic Hemangiomas Benign vascular lesions of liver. The commonest liver tumor Autopsy studies : 0.4-20 percent 3-5 decades Thought to arise from congenital hamartomas (abnormal growth of normal tissue), it can also develop from dilatation of blood vessels in a normal tissue Usually asymptomatic Incidental discovry: US++

Hepatic Hemangiomas Cavernous angiomas Hemangiomas are composed of many endothelium-lined vascular spaces separated by fibrous septa

Hepatic Hemangiomas US: well-defined, uniformly hyperechoic liver mass with peripheral feeder vessels that are characteristic of a hemangioma. Cavernous angiomas

Hepatic Hemangiomas US Diagnosis Hemangioma In practice: . Us characteristic feature . No context of neoplastic diesease . Normal liver function tests YES NO CT or MRI

Hepatic Hemangiomas CT: The pathognomonic features of caverneous hemangioma: peripheral nodular and discontinuous enhancement and progressive centripetal fill-in IV- HAP PVP DP

Hepatic Hemangiomas Diagnosis CT: venous enhancement from periphery to center

Hepatic Hemangiomas Diagnosis MRI: . Hypointense and well defined in T1 . Marked hyperintensity that increases with echo time on T2 . The same caracteristic pattern of enhacement as is seen at CT

Hepatic Hemangiomas Diagnosis MRI:

Hepatic Hemangiomas Diagnosis

Focal Nodular Hyperplasia (FNH) . Benign nodule formation of normal liver tissue . 2nd most common benign hepatic lesion . More common in young and middle age women . Male to female :5-17 . Usually asymptomatic . May cause minimal pain . Response of parenchyma to a vascular malformation or portal duct injury.

Focal Nodular Hyperplasia (FNH) . Hyperplasia with a central stellate scar radiating in to distinct nodules. . Ductular diffentiation and malformed vessels. . Rarely- encapsulated and pedunculated. . Biliary structures

Focal Nodular Hyperplasia (FNH) Diagnosis: US: Nodule with varying echogenicity Color Doppler imaging may show central vessels

Focal Nodular Hyperplasia (FNH) Diagnosis: CT . Central scar . Brisk homogeneous enhancement . Well defined . Early homogenesation . Hypodense fibrous bands and septa that arise from the scar . On delayed phase images the central scar may remain hyperattenuating . Without capsule

Focal Nodular Hyperplasia (FNH) Diagnosis: CT IV- HAP PVP DP

Focal Nodular Hyperplasia (FNH) Diagnosis: CT

Focal Nodular Hyperplasia (FNH) Diagnosis:MRI typical finding . Isointense to hypointense on T1-weighted images . Slightly hyperintense to isointense on T2-weighted images . Brisk homogeneous enhancement . Delayed enhancement of the central scar

Focal Nodular Hyperplasia (FNH) Diagnosis:MRI typical finding

Focal Nodular Hyperplasia (FNH) 20% of FNH cases are classified as nonclassic Biopsy Attal P et al. Radiology 2003;228:465-472

Hepatic Adenoma . Rare hepatic tumor . Women aged 20 to 40 years . Association with oral contraceptive use . Solitary (70%–80%) . Can be associated with right upper-quadrant pain . Risk of rupture, hemorrhage, or malignant transformation . 5-10cm . Benign neoplasm composed of normal hepatocytes no portal tract, central veins, or bile ducts . Surrounded by a capsule . Surgical resection is generally advised

Hepatic Adenoma US: CT: MRI: . Nonspecific, adenomas may be hypo, iso, or hyperechoic but are typically heterogeneous CT: . Well circumscribed without lobulation . Heterogeneous because of their mixed components of fat, hemorrhage, and necrosis . Diffuse heterogeneous arterial enhancement and iso attenuated on delayed scan MRI: . Hyper to isointense on T1 (hemorrhage) and slightly hyperintense on T2 weighted images . Same appearance on contrast-enhanced image as CT scan

Hepatic Adenoma

Liver cysts: . May be single or multiple . May be part of polycystic kidney disease . Patients often asymptomatic . No specific management required

Liver cysts: . US is sufficient to diagnose . On CT scan or MRI hepatic cysts are typically discovered incidentally

Liver cysts:

Liver cysts: HYDATID CYST

Malignant Liver Lesions

Hepatocellular Carcinoma (HCC) The fifth most common tumor Rarely occurs before age of 40 and peaks at 70 years Male to female: 4/1 Cirrhosis is the strongest predisposing factor for HCC 80% of cases of HCC developing in a cirrhotic liver Causes of cirrhosis: hepatitis (B and C virus infection), alcohol, Hemochromatosis and biliary cirrhosis Most HCCs develop by means of a multistep progression: from a low-grade dysplastic nodule to a high-grade dysplastic nodule, to a dysplastic nodule with a focus of HCC, and finally to overt carcinoma. Willatt et al Radiology: Volume 247: Number 2—May 2008

Jeong et al. AJR:185, October 2005 Hepatocellular Carcinoma (HCC) Jeong et al. AJR:185, October 2005

Importance of NC imaging Regenerating Nodules Usually too small to detect by imaging –May be surrounded by fibrotic septa –May contain iron, copper Siderotic regenerating nodules –Hyperdense on NCCT, disappear on HAP & PVP –Variable on T1, Hypointense on T2 MR, “bloom” on GRE Importance of NC imaging

Dysplastic Nodules Rarely diagnosed by US or CT Iso to hyperintense on T1 (copper) Iso to Hypo on T2 (opposite of HCC) Should not enhance much on HAP

Hepatocellular Carcinoma (HCC) Several morphological forms Massive(>3cms) Nodular (<3cms) Diffuse AFP (Alfa feto protein) Is an HCC tumor marker Values more than 100ng/ml are highly suggestive of HCC Elevation seen in more than 70%

Hepatocellular Carcinoma (HCC) US : hyperechoic, smaller tumors are hypoechoic. Heterogeneous, hypervascular US sensitivity about 75%.

Hepatocellular Carcinoma (HCC) Arterial Phase: liver(30-35 sec) HCC as supplied by arterial branch/neovascularization CT or MR Enhancement Venous Phase: HCC which is enhanced during arterial phase has lost its contrast, hence no enhancement of the tumor but rest of the liver enhances. Contrast in brightness of the lesion with respect to surrounding liver. Wash out phenomenan

Hepatocellular Carcinoma (HCC) Delayed Phase : Wash -out phenomenan persists and often exaggerated in smaller lesions. The tumor capsule capsule IV- HAP PVP DP

Hepatocellular Carcinoma (HCC)

Hepatocellular Carcinoma (HCC) MRI . Variable intensity of HCC on T1 . 35% hyper, 25% iso-, 40 % hypo . Hyperintense (T1) often well-differentiated, contain fat, copper, glycogene . Almost always hyperintense on T2 MR . The tumor capsule is hypointense on both T1- and T2-weighted images in most cases . Other Features: Focal fat

Hepatocellular Carcinoma (HCC) MRI

Hepatocellular Carcinoma (HCC) Hypovascular HCC +/- 30%

2010 AASLD Algorithm for Investigation of Small Nodules Found On Screening in Patients with Cirrhosis DIAGNOSIS : patients with cirrhosis or chronic hepatitis (even without cirrhosis) Liver nodule < 1 cm > 1 cm 4 – phase MDCT/dynamic Contrast enhanced MRI Reapeat US at 3 months Arterial hypervascularity AND venous or delayed phase washout Growing/changing character Stable Other contrast enhanced Study (CT or MRI) Yes No Arterial hypervascularity AND venous or delayed phase washout Biopsy Investigate according to size HCC Yes No Bruix J and Sherman M. AASLD Practice Guidelines , Management of Hepatocellular Carcinoma Hepatology November 2011

Fibro-Lamellar Carcinoma . Presents in young pt (5-35) . Not related to cirrhosis, AFP is normal . CT/MRI shows large mass with peripheral enhancement and typical stellate scar with radial septa showing persistant enhancement . Calcifications

Metastatic disease . Most common malignant hepatic tumor . Presence of extrahepatic malignancy should be sought in patients with characteristic liver lesions per imaging studies. Physical exam and history is very helpful. . Common primaries : colon, breast, lung, stomach, pancreases, and melanoma . Mild cholestatic picture (ALP, LDH) with preserved liver function . CT or US guided biopsy provides definitive diagnosis but not always required.

Metastatic disease Typical feature Variable US features+++ Iso, hyper or hypo echoic++ Contrast-enhanced US (CEUS) (84% accuracy) Intraoperative US (IOUS) (96% accuracy) Typical feature

Metastatic disease . MDCT are the most commonly used imaging modalities for detection and characterization of hepatic metastases . Most liver metastases are hypovascular and are best imaged during the portal venous phase (colon, stomach and pancreas) . Hypervascular metastases enhancing on the arterial phase (neuroendocrine tumors, renal cell, breast, melanoma, thyroid) . Calcification may be present with metastases from mucinous gastrointestinal tract tumors and from primary ovarian, breast, lung, renal, and thyroid cancer . Other features : Hemorrhagic or cystic metastases

Metastatic disease . On MRI, metastases are variable but are usually hypo- to isointense on T WI and iso- to hyperintense on T2 WI . Metastatic tumors with liquefactive necrosis or cystic neoplasms show higher signal intensity on T2 WI . Metastases may show central hypointensity on T2WI (coagulative necrosis, fibrin, and mucin) . High T1 signal intensity can be seen with metastases from melanoma, colonic adenocarcinoma, ovarian adenocarcinoma, multiple myeloma and pancreatic mucinous cystic tumor . Comparing T2-weighted (TE 90) and T2-weighted (TE 160) sequences, metastases become less intense Characterization . T1-weighted 3D dynamic contrast-enhanced MRI Detection

Metastatic disease

Metastatic disease

Metastatic disease . Liver-specifc contrast agent: hepatobiliary agent(T1) or reticuloendothelial agent (superparamagnetic agent; T2) T1 Multihance* Primovist* HB Agents T2 Endorem* USPIO Agents

Metastatic disease Detection+++ Diffusion MRI imaging Taouli and Koh Radiology 2010; 254:47–66

Conclusion : . MDCT and MRI are the most commonly used imaging modalities for detection and characterization of focal hepatic lesion . Imaging modalities can make diagnosis for: Hepatic cyst Caverneous hemangioma Typical FNH HCC . For others lesions biopsy will be often necessary

Monastir