Liver Tumors PDF

LIVER 2: TUMORS Von Meyenburg complex Tumor, con hoja embrionica, BENIGNO con todos tipo de celula Definition / general Also called bile duct hamartoma or microhamartoma Incidental finding...

LIVER 2: TUMORS Von Meyenburg complex Tumor, con hoja embrionica, BENIGNO con todos tipo de celula Definition / general Also called bile duct hamartoma or microhamartoma Incidental finding No clinical significance, although may resemble liver metastases to surgeons Type of ductal plate malformation, due to incomplete involution of embryonic bile duct remnants Gross description Single or multiple (20% have 4+ nodules) well circumscribed nodules, subcapsular, gray white, occasionally green; often less than 5 mm Microscopic (histologic) description Periportal small clusters of modestly dilated bile ducts, often angulated, in fibrous stroma Epithelial cells are bland Usually no / minimal inflammatory infiltrate, no atypia Hepatocellular adenoma Definition / general Benign neoplasm of hepatocellular origin arising in the noncirrhotic liver Majority are solitary; adenomatosis when > 10 lesions Female > male, strong association with oral contraceptive exposure May be asymptomatic and incidentally diagnosed due to imaging performed for an unrelated indication Symptomatic lesions present with abdominal pain or hemorrhage Risk of hemorrhage increases with size No tiene relacion a cancer, crihosis Gross description Majority are solitary and well circumscribed Uncapsulated or develop ill defined pseudocapsule Lighter in color compared to surrounding liver Foci of necrosis, hemorrhage Microscopic (histologic) description Well defined border between the lesion and background liver Composed of hepatocytes with no significant cytologic atypia Arranged as thin or only mildly thickened cell plates, 1 - 2 cells thick Characterized by unpaired arteries; interlobular bile ducts are absent, Foci of hemorrhage, ischemic changes and necrosis No cytologic atypia, atypical mitoses and portal / parenchymal invasion Focal nodular hyperplasia (FNH) Definition / general Focal nodular hyperplasia (FNH) is a benign nonneoplastic hepatic lesion, arising in a noncirrhotic liver parenchyma More common in females than males Pathogenesis is not fully understood but is thought to occur as the result of a hyperplastic response to a vascular anomaly Radiology description Well demarcated solitary hepatic lesion with a central scar in contrast CT scan and MRI Gross description Solitary, well demarcated, unencapsulated, subcapsular hepatic nodule with central stellate scar on gross examin Microscopic (histologic) description Bland hepatocytes surrounded by fibrous septa that contain artery branches and variable degree of bile ductular reaction (most important distinguishing features) and variable amount of mixed inflammatory infiltrate Portal tracts are absent except at the periphery of the lesion Hepatocytes are usually similar to those in the surrounding liver  Tumors with a capsule, not big big problem , kidney, prostata Hepatocellular carcinoma Causas: virus, hemochroma, steroides, alchol, cirrhosis Definition / general Malignant tumor with hepatocellular differentiation Highest rates of disease in Korea, Taiwan, southeast China and Mozambique and countries endemic for viral hepatitis Higher rates in blacks vs. whites (4:1); 70% male Pathophysiology Aflatoxins (mycotoxins Cirrhosis Hepatitis B virus: Hepatitis C virus: HCC is rare in abs Clinical features ▪ Symptoms: abdominal pain, ascites, hepatomegaly and obstructive jaundice; also systemic manifestations ▪ Laboratory: elevated serum AFP (70% sensitive) ▪ Screening: recommende sindrome constitutional d to use ultrasound and serum AFP in patients with chronic liver disease ▪ Metastases: initially within liver, distant metastases late to adrenal gland, bone, lung, porta hepatis lymph nodes Gross description Unifocal, multifocal or diffusely infiltrative soft tumor, paler than normal tissue, may be green due to bile Extensive intrahepatic metastases are common Hemorrhage and necrosis are common Liver usually cirrhotic, often enlarged Microscopic (histologic) description Patterns are trabecular (most common), clear cell, giant cell, pseudoglandular, sarcomatoid, solid (compact)… Presence of sinusoidal vessels surrounding tumor cells is an important diagnostic feature Scanty stroma Cells are polygonal with distinct cell membranes, abundant granular eosinophilic cytoplasm, higher N/C ratio than normal, round nuclei with coarse chromatin and thickened nuclear membrane; may have prominent nucleoli Common features are portal vein thrombosis, vascular invasion, mitotic figures Well differentiated: may resemble hepatocyte adenoma; common pattern for small hepatocellular carcinoma Moderately differentiated: most common pattern in advanced HCC Poorly differentiated: large tumor cells with hyperchromatic nuclei in compact growth pattern with rare trabeculae or bile; prominent pleomorphism, may have spindle cell or small cell areas; may not appear to be hepatocellular Cholangiocarcinoma Vesiculo biliar, ducto biliar Definition / general Intrahepatic cholangiocarcinoma is an epithelial malignancy arising from the intrahepatic biliary tree Essential features Unencapsulated, white-tan and firm intrahepatic mass Glandular malignancy with various degrees of atypia and differentiation, infiltrating a dense fibrous stroma Exclusion of metastatic adenocarcinoma by thorough review of the patient's clinical history and application of an appropriate immunohistochemistry panel Pathophysiology Chronic inflammation of the intrahepatic bile ducts is a known risk factor in cholangiocarcinogenesis Gross description Usually large, nonencapsulated, well demarcated, firm (due to desmoplastic reaction), white-tan to gray and nodular intrahepatic mass More frequent in the right lobe of the liver Satellite nodules are present in 30% Calcification is common Noncirrhotic background liver in most cases Grossly classified into 3 types in some articles: -Mass forming: hepatic parenchymal solid mass -Periductal infiltrating: infiltrates along the portal tracts, causing bile duct strictures -Intraductal growth: papillary or polypoid growth inside a dilated bile duct Microscopic (histologic) description Intrahepatic cholangiocarcinoma consists of infiltrating well formed or cribriform glands in an abundant fibrous stroma Malignant glands are lined by cells with varying degrees of atypia and pleomorphism Usually well differentiated Can be well diff, and mild atypia adenocarcinoma with mild atypia, intracytoplasmic lumina and intraluminal cellular debris; however, focal atypia with marked pleomorphism can also be present Multicentricity and perineural invasion are common