Liver Cysts Flashcards
primary liver tumor categories
non-neoplastic and neoplastic
neoplastic primary liver tumors
focal nodular hyperplasia and focal fatty change with focal fatty sparing (super rare and probably don’t need to know)
primary neoplastic liver tumors in adults
adenoma, HCC, cholangiocarinoma (epithelial)
hemangioma, (epithelioid hemangioendothelioma), angiosarcoma (mesenchymal)
cystic lesions of the liver
most are congenital - fibropolycystic liver disease
secondary metastatic liver tumors
hematopoietic malignancy and solid organ malignancy (tumors represent metastasis or origin)
benign entities
biliary microhamartoma, isolated cysts/polycystic liver disease, hepatic ademona, hemangioma
malignant entities
hepatocellular carcinoma, angiosarcoma, metastatic tumors
liver cysts that are asymptomatic
biliary microhamartoma
symptomatic liver cysts
space-occupying lesion - isolated cyst or polycystic liver disease (with or without kidney cysts)
parasitic cysts and hydatid cyst (liver)
biliary obstruction with periodic jaundice and cholangitis - choledochal cysts
fibropolycystic liver disease
a broad spectrum of inherited liver disease with shared embryologic maldevelopment as an etiology
biliary microhamartoma
less common lesions, in 6% of population, usually found incidental at autopsy or during surgeries. could potentially metastasize to liver
biliary microhamartoma histopathology
- multi cystic lesions near portal tracts (periportal) that contain bile
- small meshwork of cytologically bland, angulated duct like structures embedded within a fibrous stroma
- contain greenish brown inspissated bile in duct lumen
- cyst is lined by biliary type epithelium (cuboidal) and other side has mesothelium - same as liver surface
polycystic liver disease inheritance and gene affected
autosomal dominant - defect in ADPKD1 gene on chrom 16
polycystic liver disease population affected
75% age 70 + , women may present during pregnancy
polycystic liver disease histology
multiple unilocular cystic lesions resembling solitary cysts, lined by cuboidal to flat biliary epithelium, contains thin straw colored fluid
hepatic adenoma
benign epithelial neoplasm
hepatic adenoma risk factors
oral contraceptive use, anabolic steroids, glycogen storage disease
hepatic ademona population affected
females more than males, esp during child bearing years, women <10% are malignant, males up to 50% malignant
hepatic ademona histology
- hepatocytes with minimal atypic arranged in 1-2 cell thick cords
- no mitotic figures
- no portal areas
- large caliber vessels with little supporting stroma (bleeding risk (into peritoneal cavity) if rupture or compressed by other tissue!) / associated thrombi
treatment for hepatic ademona
- many will regress following withdrawal of steroids, contraceptive, affecting agent
- consider resecting symptomatic or if >5cm
- adenomas in men have a higher risk for malignant transformation and could be excised
hepatic adenoma presentation
hepatic mass or RUQ pain, spontaneous bleeding is common and may be life threatening
multiple adenomas
stop affecting agents, may need to be resected if cysts persist
most common primary hepatic tumor
hemangioma
Hemangioma
benign tumor of mesenchymal/vascular origin, clusters of blood-filled cavities lined by flattened endothelial cells
hemangioma populations affected
adults >children
women>men
do we biopsy hemangioma?
no because risk of hemorrhage!
histology of hemangioma
sponge-like dilated vascular channels on lower power view
cavernous vascular spaces filled with blood, separated by thin connective tissue septa, on high power view
may see thrombi since hemangioma are blood stasis - may see fibrous scarred nodules
hepatocellular carcinoma HCC
primary malignant tumor of the liver
etiology of hepatocellular carcinoma
usually develops in the setting of chronic liver disease/cirrhosis
suspicion increased in patients with previously compensated cirrhosis who become decompensated
alpha-fetoprotein AFP
glycoprotein that is normally produced during gestation by the fetal liver (cancer will restart secreting this protein)
serum concentration elevated in patients with HCC
how to spot progression of cirrhosis to hepatocellular carcinoma
surveillance imaging and serial AFP measurements, but elevated AFP may also be seen in patients with chronic liver disease without HCC (so not diagnostic but helps the probability)
hepatocellular carcinoma histology
HCC with thick cell plates and atypical cells - large, dark, pleomorphic nuclei, increased nuclear to cytoplasmic ratio, 6-10 cell plate hepatic thickness
HCC treatment
resection, but often hard to resect
-radiofrequency ablation or TACE
TACE
transarterial chemo embolization
embolic microspheres with chemo drug injected
obstruct blood supply and treat with chemo
shrinks the tumor to allow resection or to be a transplant candidate
aggressive malignant disease of mesenchymal origin (endothelium of blood vessels)
angiosarcoma
most common malignant mesenchymal tumor of the liver
angiosarcoma - but still rare as 2% of primary liver cancers
Angiosarcoma etiology
associated with exposure to environmental carcinogens including arsenic, vinyl chloride, and thorium dioxide as well as anabolic steroids
angiosarcoma patient population
older individuals, most patients who get the tumors don’t have the etiology exposures
angiosarcoma prognosis
very poor with rapid progression, high rate of recurrence and metastasis, and resistance to chemotherapy and radiation
angiosarcoma histology
high power view shows atypicl endothelial cells with enlarged hyperchromatic nuclei (which create strong anastomoses of vascular channels) infiltrating the surrounding hepatic tissue in a destructive pattern
liver metastases in cirrhotic liver
metastases rarely develop in a cirrhotic liver; therefore, a tumor found within a cirrhotic liver is HCC until proven otherwise
most common hepatic malignant tumors are secondary! so why are mets in the liver? they don’t develop there initially! metastatic tumors are more common than primary, resemble tumor or origin
why do metastases happen in the liver?
- nutrient rich dual blood supply
- humoral growth factors from pancreas
- common sites of origin with colon, stomach, pancreases, breast, lung, skin/eye
when leukemia or lymphoma involve the liver
- leukemia and lymphoma cause diffuse liver enlargement without discrete nodules and infiltration of liver parenchyma by tumor cells
- atypical lymphoid infiltrate in sinusoids
