Liver hyperplasias & neooplasias Flashcards
Solitary or multiple hyperplastic hepatocellular nodules that may develop in the non-cirrhotic Liver
Nodular hyperplasias
Causes of focal nodular hyperplasia
Long-term use of Anabolic Hormones or of Contraceptives
Epidemioology of focal nodular hyperplasia
Young to middle-aged adults
Microscopic features of focal nodular hyperplasia
- Large arterial vessels within central scar, showing fibromuscular hyperplasia & narrowing of their lumen
- Foci of intense lymphocytic infiltrates within the radiating septa
- Marked bile duct proliferation along septal margins
- Normal appearing Hepatocytes in the parenchyma between the septa, but with a thickened plate architecture (typical for regeneration)
Macroscopic features of focal nodular hyperplasia
- Well-demarcated but poorly encapsulated nodule
- Lighter colouration than the surrounding Liver
- Central gray-white, depressed stellate scar, with radiations to the periphery
Association with conditions affecting intra-hepatic blood flow
Nodular regenerative Hyperplasia
Macroscopic features of Nodular regenerative Hyperplasia
Entirely transformed Liver into roughly spherical nodules, in the absence of fibrosis
Microscopic features of Nodular regenerative Hyperplasia
- Plump hepatocytes surrounded by rims of atrophic Hepatocytes (reticulin stain
- Complications: Development of Portal Hypertension
Most common benign liver tumours
Cavernous Haemangiomas
Localisation of Cavernous Haemangiomas
Directly beneath the capsule
Macroscopic features of Cavernous Haemangiomas
Size: <2cm in diameter – Discrete, red-blue, soft nodules
Microscopic features of Cavernous Haemangiomas
Vascular channels in a bed of fibrous connective tissue
What is a hepatic adenoma?
A benign neoplasm of the liver.
What is the incidence of hepatic adenomas?
About 1 in 100,000 population.
Which population is most commonly affected by hepatic adenomas?
Women using oral contraceptives.
What genetic mutations are associated with hepatic adenomas?
HNF1α mutations: Found in 50% of cases.
β-catenin mutations: Found in 15% of cases.
Which syndrome is associated with HNF1 mutations?
Maturity-onset diabetes of the young (MODY3).
Where are hepatic adenomas most often localized?
Beneath the liver capsule.
Describe the macroscopic features of hepatic adenomas.
Size: Up to 30 cm in diameter.
Well-demarcated lesion.
Pale, yellow-tan, and frequently bile-stained.
What are the major etiologic factors for hepatocellular carcinoma (HCC)?
Chronic viral infections (HBV, HCV).
Chronic alcoholism.
Nonalcoholic steatohepatitis (NASH).
Food contaminants (e.g., aflatoxins).
Hereditary tyrosinemia (HCC develops in ~40% of cases).
How does HCC develop pathologically?
Originates from small-cell, high-grade dysplastic nodules in cirrhotic livers.
Dysplastic nodules are monoclonal with chromosomal aberrations similar to HCC.
Cells of origin: Mature hepatocytes and progenitor (ductular/oval) cells.
Characterized by genomic instability with structural and numeric chromosomal abnormalities.
What are the macroscopic features of HCC?
Patterns:
Solitary large mass.
Multifocal nodules of variable size.
Diffusely infiltrative cancer.
Appearance: Paler than surrounding liver, sometimes green-hued.
Propensity for vascular invasion, leading to:
Extensive intrahepatic metastases.
Long snake-like masses in portal vein or inferior vena cava, occasionally extending into the heart.
What are the histologic findings in HCC?
Tumour differentiation ranges from well-differentiated to anaplastic/undifferentiated.
Well and moderately differentiated forms:
Hepatocyte-like cells.
Arranged in trabecular, acinar, or pseudo-glandular patterns.
Poorly differentiated forms:
Pleomorphic tumour cells with anaplastic giant cells.
Small, undifferentiated cells.
Cells resembling spindle cell sarcoma
What is fibrolamellar carcinoma?
A distinctive variant of hepatocellular carcinoma (HCC).
