Radiology Caveats and Pearls in Liver Tumors

Transcription

1 Radiology Caveats and Pearls in Liver Tumors Greg de Prisco, M.D. Staff Radiologist Baylor University Medical Center Liver anatomy 101 Fundamentals of CT & MRI Focal Liver Lesions Benign Cysts Hemangioma FNH Adenoma Malignant Metastases HCC Cholangiocarcinoma

2 Radiologic Anatomy Review Stomach Liver IVC AO Spleen Left lobe MHV Right lobe RHV LHV

3 BD HA LPV RPV FL Left lobe CBD GB Right lobe Duo PD Panc CT Fundamental Normal Fatty CT images largely based on density!

4 CT Fundamental Normal Fatty MRI MR is more complex than CT! MR images largely based on imaging of hydrogen atoms. Steatosis: MR In phase = water + fat Normal Out of phase = water - fat

5 Steatosis: MR Normal Fatty 68 YOF with RUQ pain 68 YOF with RUQ pain

6 T1 vs. T2 T1 T2 T1 = water dark T2 = water bright T1 vs. T2 T1 T2

7 52 YOM with colon cancer Unenhanced Enhanced CT MR has superior tissue contrast! MR Enhancement arterial portal venous 3 minute 10 minute 48 YOM with carcinoid tumor Contrast timing makes a difference!

8 Gadolinium contrast - what s in a name? Generic Name Trade Name Gadodiamide Gadopentetate dimeglumine Gadoteridol Gadoversetamide Gadobutrol Gadoterate meglumine Gadobenate dimeglumine Gadoxetate disodium Omniscan Magnevist ProHance Optimark Gadovist Dotarem MultiHance Eovist Hepatobiliary Contrast Agents * * portal venous 20 minute delayed 66 YOF with colon cancer

9 Focal Hepatic Masses Variety of pathology Accurate diagnosis depends on: clinical data imaging features occasionally biopsy Focal Hepatic Masses Important clinical data history of malignancy? chronic liver dz? infection? lab abnormalities? OCP use? Focal Hepatic Masses Imaging features US appearance CT appearance MR T1 & T2 appearance Enhancement pattern Hepatobiliary contrast at MR

10 Mass lesions Benign Cyst Hemangioma FNH Adenoma Malignant Metastases HCC Cholangiocarcinoma Cysts Common Epithelial lined non vascular spaces May be numerous in ADPKD Ultrasound anechoic Unenhahanced CT hypodense T1 low signal T2 very high signal Nonenhancing Cysts

11 Hemangioma Most common benign solid liver tumor (20%) Endothelial lined vascular spaces F > M Hemangioma Ultrasound hyperechoic with or without central hypoechogenicity Unenhanced CT hypodense

12 Hemangioma Ultrasound hyperechoic with or without central hypoechogenicity Unenhanced CT hypodense T1 low signal T2 very high signal, mimic cysts Hemangioma 3 enhancement patterns Classic peripheral, nodular, interrupted, persistent Uniform, homogeneous, persistent Features of classic with nonenhancing central scar Enhancement follows blood pool in all phases!

13 Pitfalls Metastasis

14 Focal Nodular Hyperplasia 2 rd most common liver tumor 3% general population 8% all primary hepatic tumors Child bearing females Focal Nodular Hyperplasia Hyperplastic response to a congenital vascular malformation Often have a central scar Contain bile ducts Can occur with hemangiomas Focal Nodular Hyperplasia Stealthy on unenhanced exams T1 iso or slightly hypointense, central scar hypointense T2 majority of lesion isointense or mildly hyperintense, central scar hyperintense

15 Focal Nodular Hyperplasia Enhancement Uniform arterial uniform enhancement except for scar Focal Nodular Hyperplasia Enhancement Uniform arterial uniform enhancement except for scar Enhances similar to liver in portal venous phase Focal Nodular Hyperplasia Enhancement Uniform arterial uniform enhancement except for scar Enhances similar to liver in portal venous phase Delayed enhancement of central scar

16 Focal Nodular Hyperplasia Enhancement Uniform arterial uniform enhancement except for scar Enhances similar to liver in portal venous phase Delayed enhancement of central scar Iso to hyperintense to liver on delayed hepatobiliary images Hepatic Adenoma Benign proliferation of hepatocytes Young women Pathogenesis Oral Contraceptives (1960) Longterm and high dose Anabolic steroids Glycogen storage disease Multiple Malignant transformation Unenhanced CT may be iso to hypodense, hyperdense with acute hemorrhage Hepatic Adenoma

17 Unenhanced CT may be iso to hypodense, hyperdense with acute hemorrhage T1 often have fatty deposition May be T1 hyperintense with hemorrhage T2 predominantly hyperintense Hepatic Adenoma Enhancement Hypervascular Hepatic Adenoma Heterogeneous intratumoral hemorrhage, necrosis, and fat Enhancement Hypervascular Hepatic Adenoma Heterogeneous intratumoral hemorrhage, necrosis, and fat +/ capsule appearance