1. Tchelepi H. Ralls PW. Ultrasound Quarterly. 20(4):155-69, 2004 Dec.
Journal Reading Ultrasound of Focal Liver Masses-Image Finding in Common Liver Lesions
Int 許致博
Tchelepi H. Ralls PW. Ultrasound Quarterly. 20(4):155-69, 2004 Dec.

2. Outline Simple hepatic cysts Carvenous hemangioma Hepatic metastasis
Hepatocellular carcinoma
Cholangiocarcinoma
Liver abscess
Focal nodular hyperplasia / liver cell adenoma

3. Simple hepatic cysts Male : Female = 1 : 4
Frequency increases with age
< 60 y/o  < 1% of pt
> 60 y/o  3% ~ 7%
S/S: rare. May occur from mass effect, rupture, hemorrhage, infection
Gaines PA, Sampson MA. The prevalence and characterization of simple hepatic cysts by ultrasound examination. Br J Radiol. 1988;62:335–337.

4. Simple hepatic cysts A cyst is found in a young pt:
Polycystic liver disease
Autosomal dominant polycystic kidney disease
von Hippel-Lindqu disease
Other: echinococcal disease, residua from inflammatory disease, cystic neoplasia

5. Sonographic appearances
Well defined, thin epithelial lining and imperceptible wall
Watery fluid, echo-free lesion
Distal sonic enhancement
Usually solitary
Round or oval
Size from < 1 cm to > 20 cm

6. Simple hepatic cysts Sonography: the best tool, better than CT
Rarely simulate clinically significant lesions  require no further evaluation
Polycystic disease: different from simple hepatic cysts: more irregular and more often internal debris
Thick septations or solid component: biliary cystadenomas
Equivocal : biopsy

7. Polycystic disease
Debris (+)
Multiple
Irregular
Septation (+)

8. Biliary cystadenoma
Irregular
Thicker septations

9. Cavernous hemangioma
Commonest benign hepatic neoplasm: 1~4% of individuals
Female > Male
S/S:
Rare. Mass effect may occur
Rupture with hemorrhage and thrombocytopenia has been reported

10. Sonographic appearances
Small hemangioma
Echogenic
Well-defined
Distal sonic enhancement

11. Sonographic appearances
Large hemangiomas
Thrombosis, necrosis: mixed echogenicity or even hypoechoic
Circumferential echogenic rim contifuous to normal liver  strongly suggestive of hemangioma
Moody AR, Wilson SR. Atypical hepatic hemangioma: a suggestive
sonographic morphology. Radiology. 1993;188:413–417.

12. Delay-phase CT
Incomplete filling
Well-defined echogenic rim
Hypoechoic
Well-defined echogenic rim

13. Sonographic appearances
Color Doppler: internal flow is in common. Hypervascularity is rare  Need further evaluation  MR + c or CT + c
Internal flow is more common in larger lesions

14. Further evaluation
Typical hemangioma usually do not require further evaluation
Atypical hemangiomas may require further evaluation  especially in pt with known malignancy
Biopsy may be necessary

15. Hepatic metastasis In the U.S.:
Incidence: 18~20 times than HCC
Produce S/S: 10 times than HCC
In a autopsy series, 38% of pt with ca had hepatic metastases
Most common ca include: lung, colon, pancrease, breast, stomach
Edmonson HA, Craig JR. Neoplasms of the liver. In: Shiff L, Shiff ER, (eds). Diseases of the Liver. 5th ed. Philadelphia:Lippincott;1987:1147.

16. Sonographic appearances
90% of pt: multifocal
Any appearance may occur
Usually inhomogeneous
A target or bull’s eye with varying rings of hypo- and hyperechogenicity are common
Ill-defined infiltrative dz with focal nodularity
Simulate simple cysts or classic hemagiomata: uncommon

17. Sonographic appearances
Liver meta from pancreatic ca
Predominantly hypoechoid
Liver meta from colon ca
Halo appearance: bull’s eye sign

18. Where is the primary ca? Sonographic appearance is a poor predictor
Unlike simple cyst  irregular wall
Cystic lesion  SCC or GIST (liver meta from esophageal ca)
Sonographic appearance is a poor predictor
Certain patterns may be suggest:
Necrotic metastases: SCC and sarcomas (especially GIST)
Cystic lesions: SCC
Lesions with fluid-fluid levels: GIST (leiomyosarcoma)
Large to moderate-sized hyperechoic with microcalcifications: colonic primary

19. Hepatocellular carcinoma
Commonest primary liver cancer: 80% primary liver malignancies in the U.S.
Less common than hepatic metastases
Associated with HBV and HCV. HCV > HBV
85% of pt with HCC: cirrhosis or pre-cirrhotic conditions
Alcoholic cirrhosis related HCC: 10% of autopsied pt
Sonar is a part of screening for HCC

20. Sonographic appearances
Findings are variable for advanced HCC
Small HCCs (< 5 cm): 75% hypoechoic
As HCCs enlarge: hypoechoic peripheral rims
Further progression: numerous and heterogeneous
HCCs present clinically: usually multifocal
Screen situation: usually small lesions

21. Sonographic appearances
Some HCC (even small): fatty metamorphosis  ↑echogenicity
Vascular invasion is common: portal vein > hepatic vein
Bile duct obstruction: extrinsic compression > duct invasion
HCC
3 x 1.5 cm
Hypoechoid
Internal flow

22. HCC arising in normal liver
HCCs arise in normal liver: uncommon
Occur at a younger age
Single, well circumscribed lesions, lobulated margins, fibrolamellar HCCs
2% of HCC
25% ~ 50% HCC in young adults
Echogenicity: variable
Central scar: nonspecific
High prevalence of calcification: also common in all varieties of HCC (20 ~ 25%)
HCC with center scar

23. Hepatic metastasis and HCC
May be impossible to distinguish
Distinguish from lab data
Underlying liver dz favors HCC
Invasion of the portal or hepatic veins favors HCC  < 5% of pt with portal venous invasion occur in metastatic dz
Biopsy

24. Cholangiocarcinoma Arise from the bile ducts
10% of all primary liver cancers
Peripheral (PCC) and hilar (Klatskin tumor)
PCC is 3 times > hilar cholangiocarcinoma in the U.S.
PCC is usually a large tumor

25. Cholangiocarcinoma Hilar cholangiocarcinoma: early ductal obstruction
Associated with:
Hemochromatosis
Ulcerative colitis
Caroli disease
Choledochal cyst
Hemochromatosis: 9% of PCC and 18% of hilar cholangiocarcinoma

26. Cholangiocarcinoma Hard to visualized with all modalities
Sonography is superior to multiphase helical CT about hilar cholangiocarcinoma
Sonographic findings are variable:
Hypoechoid? Hyperechoid?
Author: slightly hypoechoic lesions are more frequent
Cholangiocarcinoma
Invade left protal vein

27. Liver abscess
Incidence: worldwide, pyogenic liver abscess < amebic liver abscess
In U.S.
Pyogenic > amebic.

28. Pyogenic liver abscess
Mild and vague S/S
Pyogenic: usually as a complication of other condition (ex immunocompromised, older pt, cholecystitis, bile duct obstruction, trauma, surgery)
E. coli is most common
Polymicrobial infections are common: 50% of pt

29. Sonographic appearances
Typical appearance:
Poorly defined
Irregularly marginated
Hypoechoid
Irregular areas of increased echogenicity are frequent
Gas present. Diffusely hyperechoic appearance may be noted due to large amounts of gas
Variable sonographic appearance
Clusters of small lesions: “cholangitic” abscesses
Usually can’t D/D with tumor necrosis

30. Fluid-debris level
Solid –appearing mass R/O malignancy
Hyperechoic region in the center
 Air bubble

31. Pyogenic liver abscess
Tx: percutaneous image-guided abscess drainage better than surgery
Multiloculated abscess also can be drained with one catheter

32. Amebic liver abscess Provoking S/S High-risk populations: Young
Hispanic males
HIV-positive pt

33. Sonographic appearances
Hypoechoic appearance with fine, homogenous, low-level echoes throughout
Tend to well-defined than pyogenic abscess
Tend to have a round or oval shape
Difficult to D/D

34. Amebic liver abscess
Tend to be more well-defined ???

35. Initially, multiseptate fluid collection
2 weeks later after treatment
Decrease size
Development of a thick wall
3 months later after treatment

36. Pyogenic v.s. amebic abscesses
Confusion  aspiration for D/D
Percutaneous driagnostic aspiration: 15% of amebic abscess pt
Percutaneous drainage of amebic liver abscess is not indicated

37. Focal nodular hyperplasia (FNH) Liver cell adenoma (LCA)
Rare benign liver tumors
Unknown cause
LCA is associated with oral contraceptives
Other factors associated with LCA: glycogen storage dz, androgen administration, tyrosinemia, galactosemia, diabetes, cirrhosis
FNH v.s. oral contraceptives: controversial
Male < Female
S/S
FNH is a clinically insignificant lesion
LCA can cause morbidity and mortality related to hemorrhage or malignant change
A focal lesion may show both FNH and LCA

38. Sonographic appearances
FNH:
Echogenicity close to normal liver
High flow
Central scar: also seen in other lesions
Lesions present high flow:
Focal nodular hyperplasia
HCC
Metastatic lesions

39. Focal nodular hyperplasia
Echogenicity close to normal liver
High flow
Stellate area of low density typical of focal nodular hyperplasia

40. Sonographic appearances
Similar to FNH
Variable appearance. If bleeding  hypoechoid (if old) or hyperechoid
Usually solitary, marginated, encapsulate mass

41. Liver cell adenoma
Focal nodular hyperplasia

42. Sonographic appearances
FNH:
More homogeneous
LCA:
More inhomogeneous
Usually hypoechoic
D/D
Technetium sulfur colloid liver spleen scanning
FNH: liver exhibits normal or increased uptake

43. Thanks for your attention!