Objectives. HCC Incidence and Mortality. Disclosure Statement HCC. Imaging of Hepatocellular Carcinoma. Treatment of Hepatocellular Carcinoma

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1 Imaging of Hepatocellular Carcinoma and the use of LI RADS Treatment of Hepatocellular Carcinoma Aaron D. Anderson, D.O. AOCR April 2015 Objectives Show how the use of LI RADS can simplify the diagnosis and reporting of HCC in high risk patients Show how to use LI RADS to add confidence to your diagnosis of HCC Discuss the radiologist s role in the management and treatment of HCC Disclosure Statement NO DISCLOSURE: Neither I nor my immediate family members have a financial relationship with a commercial organization that may have a direct or indirect interest in the content of this presentation. HCC Incidence and Mortality Primary liver cancer (including intrahepatic bile duct cancer) is the fifth most common cause of cancer death in men and the ninth most common cause of cancer death in women. Over the past two decades, incidence rates have increased in people of all races and in both sexes. Overall mortality rates have been rising an average of 2.6 percent each year over Men are about three times as likely as women to develop liver and intrahepatic bile duct cancers, and more than twice as likely as women to die from these cancers. Asians/Pacific Islanders and American Indians/Alaska Natives have higher incidence rates of these cancers than people of other races/ethnicities. HCC Incidence and Mortality Almost all cases of liver cancer in the United States occur in people with alcohol related cirrhosis or who are chronically infected with hepatitis B virus (HBV) or hepatitis C virus (HCV). Obesity, diabetes, and iron storage disease are other risk factors for liver cancer. Vaccinating for HBV provides long term protection from HBV infection and has been shown to lower the risk of liver cancer in children, although it is not yet known whether it lowers the risk in adults. There is no standard or routine screening test for liver cancer. HCC Hepatocellular carcinoma differs from most malignancies because it is commonly diagnosed on the basis ofimaging features alone, without histologic confirmation. Also, biopsy of hepatocellular carcinoma carries a theoretical risk of seeding cancer cells along the needle tract, which may lead to tumor recurrence after liver transplantation. This risk is small (2.7%). Use of trocars during biopsy has not been associated with tumor seeding. There is no reliable tumor marker for hepatocellular carcinoma. Measurement of the serum levels of AFP is used as an aid to diagnosis and in screening. A rise in the serum level of AFP in a patient with cirrhosis should raise concern that hepatocellular carcinoma has developed. However, an elevated level of AFP is not specific for hepatocellular carcinoma; AFP may be elevated in flares of viral hepatitis. When a cutoff value of 20 μg/l is used, measurement of serum AFP level has a sensitivity of only 60%. 1

2 Our Role MANY RADS Diagnose Treat in select cases BI RADS HI RADS PI RADS Lung RADS 2

3 LI RADS The Liver Imaging Reporting and Data System (LI RADS) was created to standardize the reporting and data collection of CT and MR imaging for hepatocellular carcinoma (HCC). This method of categorizing liver findings for patients with cirrhosis or other risk factors for developing HCC allows the radiology community to: Apply consistent terminology Reduce imaging interpretation variability and errors Enhance communication with referring clinicians Facilitate quality assurance and research LI RADS Versions Simplified More Illustrations New material on hepatobiliary agents Reporting templates for CT and MR New Flash Cards for Quick Reference My experience with LI RADS Body MRI/Abdominal Imaging fellow UC Davis UC Davis Body Section wide implementation of LI RADS beginning July 2013 Well received by gastroenterologists/hepatologists, oncologists, and surgical oncologists Use in current practice Available at: Safety/Resources/LIRADS I just google: LI RADS ACR or leave a link on my desktop Interactive document Quick reference flash cards 6 pages LI RADS 3

4 Technique MRI Sequences: T2 FSE or SSFSE, T1, T1+C, T1 subtraction, DWI, T1 weighted in/out of phase Phases of enhancement Late arterial, portal venous, delayed, hepatobiliary Hepatobiliary agents? CT Arterial and PV phases required Precontrast and delayed suggested Considerations Patient prep Patient screening prior to MRI Renal Function Acites: Paracentesis prior to MRI 4

5 LI RADS THE TABLE High risk Patient Alcohol related cirrhosis Chronic Hepatitis B Chronic Hepatitis C Obesity Diabetes Iron Storage disease No history? Imaging features of cirrhosis and sequellae of portal hypertension LR1 Definitely Benign Cyst Hemangioma Vascular anomaly Perfusion alteration Hepatic fat deposition or sparing Hypertrophic pseudomass Confluent fibrosis Focal scar Observation that spontaneously disappears at followup LR1 Examples Hemangioma T2 hyperintensity, follows blood pool Perfusion alteration Transient Hepatic Attenuation Differences (THAD) Transient Hepatic Intensity Differences (THID) Transient Difference in Arterial Perfusion TDAP Isolated or associated with another lesion (classic = hemangioma) Typically peripheral, wedge shaped or amorphous Cannot confirm a lesion on subsequent phases, or on other sequences (T2, DWI, IP/OOP) LR2 Probably Benign List of definite benign entities and probable benign entities is essentially the same. The categorization as LR 1 or LR 2 depends on the level of certainty. Adds LR 2 cirrhosis associated nodule LR2 Cirrhosis Associated Nodule Cirrhosis associated nodules represent a histological spectrum: cirrhotic nodules (CNs) (which include regenerative nodules (RNs)) => dysplastic nodules (LGDNs) => high grade dysplastic nodules (HGDNs) => HCC. Cirrhosis associated nodules with the imaging features below may be considered probably benign (all of the following) and categorized as LR 2: Diameter < 20mm AND Homogeneous AND Iso enhancement to background cirrhotic nodules in all phases AND Differ from background nodules by having one or more of the following features: Distinctly larger than background nodules (but still < 20mm) Mild to moderate CT hyper attenuation Mild to moderate T1 hyper intensity Mild T2 or T2* hypo intensity Moderate or marked T2 or T2* hypo intensity (e.g., iron rich cirrhosis associated nodules) 5

6 LR2 Examples LR3, LR4, LR5 6

7 Washout Capsule Threshold growth Major Criteria Washout Visually assessed temporal reduction in enhancement relative to liver from an earlier to a later phase resulting in portal venous phase hypo enhancement or delayed phase hypo enhancement. In the arterial phase, the observations may be hyper enhancing or hypo or isoenhancing. Capsule AKA pseudocapsule or capsule appearance Peripheral rim of smooth hyper enhancement in the portal venous phase or delayed phase that unequivocally is thicker or more conspicuous than the rims surrounding background nodule. The degree of enhancement of the capsule usually increases from early to later phases. Threshold Growth Increase in diameter of amasscompared to its baseline by a minimum of 5 mm AND depending on the time interval between examinations, by the following amounts: <6 months: >50% diameter increase >6 months: >100% diameter increase per year; e.g. >100% in 1 year, >150% in 1.5 years, >200% (tripling) in 2 years, quadrupling in 3 years, etc. 7

8 LR3 Examples 8 mm focus LR4 Examples 8

9 LR5 Examples LR5V Example 9

10 Ancillary Features Imaging features that modify likelihood of HCC. In isolation, these features do not permit reliable categorization of observations and hence are considered ancillary. Radiologists may at their discretion apply ancillary features to adjust LI RADS category as follows: Features that may favor malignancy to upgrade category by one or more categories (up to but not beyond LR 4). Ancillary features cannot be used to upgrade category to LR 5to maintain congruency with OPTN. Ancillary features that may favor malignancy can favor malignancy in general or specifically favor HCC Features that may favor benignity to downgrade category by one ormore categories. Ancillary Features that may favor malignancy Hepatobiliary phase hypo intensity Mild moderate T2 hyper intensity Restricted diffusion Distinctive rim* Corona enhancement* Mosaic architecture* Nodule in nodule architecture* Intra lesional fat* Lesional iron sparing Lesional fat sparing Blood products Diameter increase less than threshold growth *Features that specifically favor HCC as opposed to malignancy in general. Ancillary features that may favor benignity Homogeneous marked T2 hyper intensity Homogeneous marked T2 or T2* hypointensity Hepatobiliary phase iso intensity Undistorted vessels Parallels blood pool enhancement Diameter reduction Diameter stability 2 years Applying Ancillary features and Tie breakers Treatment Resectable vs Nonresectable Radiofrequency Ablation/Microwave Ablation Percutaneous Intraoperative US guided TACE TARE Transplant 10

11 Treatment outcome Dictates what we dictate Predictors of poor outcomes in HCC are common to all therapeutic approaches and include: More than three tumors Tumor size larger than 5 cm Portal vein invasion Intrahepatic metastases Absence of a tumor pseudocapsule Most important factors appear to be vascular invasion and liver function RFA Indications Primary treatment instead of partial hepetectomy for lesions < 3 cm Unresectable small HCC Recurrent small HCC Bridging therapy before liver transplantation 3 lesions or less Complete response: 3 cm (80%), 3 5 cm (50%) Location Diaphragm Central near large vessels Heat sink Thrombosis Damage to biliary system and gallbladder Morbidity 7%, Mortality 1% Pneumothorax, bleeding, abscess, tract seeding. <1% each RFA CT and US guided Place probe with US Time with breathing More precise placement Confirm with CT w or wo contrast Monitor burn real time with US General anesthesia Same day vs overnight stay CT prior to discharge Baseline Assess for complications Pre and postprocedure abx Follow up CT 6 months, then yearly 11

12 References ACR Liver Imaging Reporting and Data System v2014 Forner A. et al. Hepatocelluler Carcinoma. Lancet ;379(9822): National Cancer Institute. Annual report to the nation on the status of cancer: March National Cancer Institute. A Snapshot of Liver Cancers. November 2014 Sinead H. et al. Hepatocellular Carcinoma: Illustrated Guide to Systematic Radiologic Diagnosis and Staging According to Guidelines of the American Association for the Study of Liver Diseases. RadioGraphics :6, Gervais D. et al. Society of Interventional Radiology Position Statement on Percutaneous Radiofrequency Ablation for the Treatment of Liver Tumors. J Vasc Interv Radiol :S342 S347 Poon RT. et al. Clinicopathologic features of long term survivors and disease free survivors after resectionofhepatocellular carcinoma: a study of a prospective cohort. J ClinOncol 2001;19: McGahan J. Dodd G. Radiofrequency Ablation of the Liver: Current Status. AJR 2001;176:3 16 Shah D. et al. Current oncologic applications of radiofrequency ablation therapies. World J Gastrointest Oncol (4):