Benign liver tumors Flashcards
What are the most frequent liver lesion identified prenatally?
Hemangioma
mesenchymal hamartoma
hepatoblastoma
How are hepatic hemangioma classified?
Hepatic hemangiomas are benign tumors. they are classified as:
Focal
Multifocal
Diffuse
What complications are associated with diffuse hepatic hemangioma?
- Kassabach-merit phenomena: consumption coagulopathy, thrombocytopenia (as low as 50 000), anemia, enlarging vascular lesion.
- abdominal compartment syndrome
- cardiac failure due to increase output and shunting
- hypothyroidism (secrete 3 iodothyronine which inactivates thyroid hormone)
Typically, KM phenomena is associated with kaposiform hemangioendothelioma.
What is the cutaneous counterpart to focal hepatic hemangioma?
Congenital rapidly involuting hemangioma (RICH)
Are fully form at birth and then undergo rapid involution. May be identified prenatally - has to be part of ddx.
May present transient thrombocytopenia - will correct within a week. not the same as Kasabath-meritt phenomenon (persitent thrombocytopenia)
Association between liver hemangioma and Beckwith-widemann syndrome
What is the cutaneous counterpart of multifocal / diffuse hepatic hemangioma?
infantile hemangioma. Not present at birth, appears in weeks to month after. grows during first year of life, with marked increase in size during first 3 monhts. Than involutes over next 5-7 years of age.
if patient has 5 infantile hemangiomas or more, screen for hepatic
What is the difference between multifocal and diffuse liver hemangiomas?
Multifocal occurs randomly in liver. Diffuse replaces the entire liver.
If undetected, multifocal can lead to diffuse disease.
What is the management of a complicated diffuse congenital hemangioma?
Treat aggressively.
Compartment: decompressive laparotoma
Hypothyroidism: correct with supraphysiological doses
Cardiac failure : attempt at angioembolization. Consider transplant.
Treatment with propranolol, steroids, vincristine.
What is the appearance of a liver hemangioma on antenatal US
50% have punctate calcifications (due to bleeding)
heterogenous lesions, with hypo/hyper echoic features.
brisk vascular flow on doppler
What are mesenchymal hamartomas?
mixed solid / cystic mass of disorganized mesenchyme. endothelium (vascular) or biliary tree epithelium which doesn’t communicate with the biliary tree.
Porous characteristics of this lesion allow formation of large cysts!
What are the US charactesistics of a mesenchymal hamartoma?
Can be a large cysts with septation or multiseptated solid cystic apparance
May consider early delivery if hydrops. Reports of c-section due to increase in abdominal girth.
AFP usually low .
At what age does mesenchymal hamartoma typically presents?
2 yo
2nd most common liver tumor, after hemangioma.
Mesenchymal hamartoma has a strong predilection for R lobe.
Do mesenchymal hamartoma hold a malignant potential.
MH are benign lesion but there are reports of association between them and undifferentiated embryonal sarcoma. Confusion lies where the MH is a large cytic structure with thin septas,an appearance which can be shared with undifferentiated embryonal sarcoma.
Of note, spontaneous regression of MH has been described.
What is the standard treatment for mesenchymal hamartoma.
Resection.
wedge if possible, if not than anatomic resection.
transplantation has been described.
Observation is an option. ideally not for morphology which could be confused with undifferentiated embryonal sarcoma (large cystic with septa), but for bulky, biopsy confirmed MH. Follow closely.
Unroofing of cystic MH doomed to increased recurrence risk.
What is the histological definition of focal nodular hyperplasia?
Thought to arise from area of focal ischemia and regeneration.
Abnormal architecture of a benign hepatocyte, bile duct proliferation and vascular anomalies
all structure of the portal triad are present but the architecture is innapropriate
Amongst which age group is FNH most common?
preteen - average 9 yo
Associated with type-1 glycogen storage deficiency and post chemo.
