1. Approach to benign liver
lesion
Dr.Sandra Johns
PG resident
DrSMCSI Medical college
2. Introduction
• Focal lesions of the liver are characterized based upon underlying
histology.
• Common benign lesion of the liver includes hepatic cysts and cystic
lesions, Hemangiomas, Hepatic adenoma ,Focal nodular hyperplasia ,
regenerative nodules and hepatic abscess.
3. Modality and imaging protocol
• USG and doppler
• MDCT
Multiphase computed tomography (CT) including hepatic arterial
phase, portal venous phase, and delayed phase (equilibrium, 3
min) is the protocol of choice for evaluation of hepatic lesions.
Precontrast acquisition may be helpful in evaluation of cysts and
areas of spontaneous hyperdensity.
4. MRI : Routine sequences – T1,T2, STIR , DWI
• In- and out-of-phase imaging and fat suppression techniques can
demonstrate areas of microscopic and macroscopic fat, respectively.
Post contrast imaging
1.Dynamic Imaging (in the case of Gd chelates)
2.Hepatobiliary phase imaging
CT and USG guided biopsy and aspiration
5. Demographics and age
• Benign lesions such as FNH and adenoma are more common in
younger to middle-aged patients, whereas hemangiomas are found in
all ages.
• All 3 lesions also have a female predilection.
• Exogenous estrogen such as OCP use can accelerate the development
of adenomas and FNH, with the former also increased in prevalence
in those using anabolic steroids and glycogen storage disease.
6. Clinical features
• Hemangiomas and FNH tend to be incidental findings and
asymptomatic, though large lesions may cause right upper quadrant
pain from mass effect and capsular distension.
• Adenomas and may present with acute symptoms secondary to
rupture and subsequent hemoperitoneum.
7. Characterization of liver masses
Density of the lesion
• If the lesion is of near water density, homogeneous, has sharp
margins and shows no enhancement, then it is a cyst.
Then consider simple hepatic cyst vs complex cyst
• If the lesion is not cystic, next step is to determine whether the lesion
could be haemangioma, since this is by far the most common tumour
of liver
8. If it is not a cyst nor a hemangioma, then we further have to study the
lesion.
Based on the enhancement pattern, we divide masses into
hypervascular and hypovascular lesions.
10. Size of the lesions
• Lesions larger than 1 cm can be characterized in most cases.
• Small hepatic lesions (<1 cm) are difficult to characterize and biopsy,
but have a high probability of being benign (>80% even in
patients with known malignancy) thus close clinical follow-up and
monitoring for progression may be the next most appropriate step.
• In most cases these lesions represent cysts, hemangiomas, or
biliary hamartomas.
• Lesions <0.5 cm in patients without risk factors (ie, no known
malignancy, hepatic dysfunction, hepatic malignancy risk factors, or
symptoms attributable to the liver) do not require follow-up
12. Enhancement Pattern
• MDCT in hepatic protocol
• MRI in conventional and hepatocyte specific contrast agents.
13. Simple cyst
• Often incidental and asymptomatic, they are most common in
middle aged women (5:1), although cysts can be seen at any
age and may demonstrate mass effect if large enough.
• They be complicated by hemorrhage, rupture, or secondary
infection.
• Lined by cuboid epithelium identical to bile ducts, indicating
biliary origin.
• May cause increased alkaline phosphatase or bilirubin if there
is mass effect upon the bile ducts.
14.
15. Complex cyst
Hydatid cyst
• Infection : Echinococcus granulosus
• Larvae migrate from the gut and embedded in liver where they encyst and
develop.
• Wide range of imaging appearance from a simple cyst (indistinguishable
from true hepatic cyst) or complex cyst with following features
a)Debris ,made up of dead scolces
b) Daughter cysts
c) Membraneous septations
4) Calcification
16.
17. Hepatic pyogenic abscess
In early stages abscess may mimic solid tumours such as mestastases
on all imaging techniques and aspiration or biopsy may be necessary
for diagnosis.
As the abscess slowly liquefies , a thickness and irregular wall appears
and the necrotic centre appears cystic.
18. • USG: Thick and irregular wall with central necrosis and echoes.
Peripheral vascularity with absent internal vascularity.
21. Biliary Cystadenoma
• Biliary cystadenomas, also known as mucinous cystic neoplasms of
the liver, are uncommon benign cystic neoplasms of the liver.
• Symptoms: Right upper quadrant pain, Juandice .
22. Ultrasound
• A biliary cystadenoma appears as a unilocular or multilocular cyst
with enhanced through transmission. The content of the cysts may
range from completely anechoic to having low-level echoes from
blood products, mucin, or proteinaceous fluid.
• Mural nodules and papillary projections may project into the cyst
lumen.
23. MRI: The T1 and T2 appearance of the cyst varies with the cyst content
24. Cystic metastases
From ovarian , colonic and squamous cell tumours
Differentiation may be impossible on imaging alone and guided
aspiration may be required.
26. Hemangioma
• Commonest benign liver lesion
• Composed of vascular channels of varying size lined with
endothelium.
• Haemangiomas with size 2cm to 4 cm possess characteristic features
that facilitates a confident imaging based diagnosis.
28. MDCT
• non-contrast: Often homogeneous hypoattenuating (<20 Hounsfield
units) relative to liver parenchyma 23
• late arterial phase: typically show discontinuous, nodular, peripheral
enhancement (small lesions may show uniform enhancement)
• portal venous phase: progressive peripheral enhancement with more
centripetal fill-in
• delayed phase: further irregular fill-in and therefore iso- or hyper-
attenuating to liver parenchyma
29.
30. MRI
• Most sensitive and specific imaging tool for diagnosis of hemangioma.
• T2w spin echo(Long TE of 120 to 160)- Bright lesions (light bulb
appearance)
• Post contrast study : Similar enhancing pattern of MDCT
31. Focal nodular hyperplasia
• Second most benign solid tumour
• F>>M
• Asymptomatic or Hepatomegaly and right upper quadrant pain
32. Ultrasound findings of the lesions are usually non specific.
Well circumscribed and isoechoic to liver.
Central scar shows hypervascularity.
Mass effect
33. MDCT
• On unenhanced CT, FNH are subtle and well defined which may show
mass effect displacing the adjacent vessels.
• late arterial phase: Homogenous enhancement except to
the central scar and large feeding vessels may be present
• portal venous phase: Disappears and become iso-
enhancing to the liver.
• delayed phase: Scar will show enhancement
34. MRI
T2 –hyperintense
T1-Iso to hypointense
The central scar is hypointense in T1 and T2 sequence.
Iv gadolinium contrast enhancement are similar to the contrast CT.
Hepatocyte specific contrast agent – FNH vs Hepatic adenoma.
35. Hepatic adenoma
• Rare benign tumour
• Association: Anabolic steroid, Glycogen storage disease.
• They are frequently asymptomatic but as they enlarge it might
outgrow the blood supply and cause necrosis , haemorrhage.
36.
37. • NCCT – Uncomplicated lesions are isodose to liver. In the presence of
haemorrhage the lesion will be hyperdense.
• In the arterial phase the lesion will show uniform hyperenhancement
in arterial phase and rapidly merge with surrounding liver in the
postal phase.
• MRI- Hyperintense in T1 and T2 sequence with uniform arterial
enhancement in conventional contrast MRI
38. • FNH vs Hepatic adenoma
Histologically FNH is composed of normal hepatocyte , bile duct ,kuffer
cell and fibrous septa. In FNH the biliary element are not connected to
the biliary tree. This help to differentiate FNH from adenoma while
using hepatocyte specific MRI contrast agent.
39. Regenerative nodules
• Non neoplastic nodules in cirrhotic liver
• The nodules are isointense or hypointense in all MRI sequences.
Dysplastic nodules
Arterial enhancement and absent washout in portovenous phase
