<unk>  is an uncommon benign liver<unk>  that is most commonly associated with oral contraceptive use in women of childbearing age. It was first described by Edmondson in 1958 as an encapsulated liver tumor that does not contain bile ducts. In 1970s several case series supported the hypothesis of an association between oral contraceptives and<unk> . It is generally asymptomatic, the typical clinical manifestations include spontaneous rupture or hemorrhage leading to acute abdominal pain with progression to hypotension and even death. There are no specific physical examination findings associated with<unk> . The liver function tests and serum tumor markers are usually normal, but may be raised secondary to necrosis or hemorrhage and alkaline phosphatase may be raised in<unk> tosis. The causes of<unk>  include; oral contraceptive medications, long term anabolic androgenic steroids, obesity, metabolic syndrome and glycogen storage diseases. It is more commonly seen in western countries where they are exposed to higher doses of oral contraceptive medications. The estimated incidence is 3 per 1,000,000/year and is 3 to 4 per 100,000 with long term oral contraceptive use. The<unk> s are classified on the basis of molecular patterns called phenotypic genotypic classification into 04 groups including; HNF1 alpha inactivated<unk> , beta catenin activated<unk> , inflammatory hepatic<unk>  and unclassified type<unk> . The exact pathogenesis of<unk>  is still unknown, however, its association with oral contraceptive use is well established. Other associations of<unk>  include; long term use of anabolic androgenic steroids and glycogen storage diseases as well. It<unk> s been linked to mutations in HNF1a and beta catenin genes. On gross pathology, the<unk>  appears as solitary or multiple, unencapsulated and well demarcated lesion, which can occasionally be pedunculated or encapsulated that can also form multiple masses. The intra tumoral hemorrhage can give rise to soft, necrotic, red brown lesion on gross appearance. The microscopic features of<unk>  include benign hepatocytes arranged in mildly thickened cell plates with a preserved reticulin network and thin walled arteries. The arteries and arterioles are not accompanied by other portal tract elements such as bile ducts, portal veins or fibroconnective tissue.<unk>  must be differentiated from focal nodular hyperplasia, large regenerative hyperplasia, hepatocellular carcinoma in noncirrhotic patients & fibrolamellar hepatocellular carcinoma, cholangiocarcinoma and metastases. If left untreated, there is 30% bleeding risk. Complications include; bleeding, rupture and malignant transformation. The CT scan findings of<unk>  include; non lobulated, well marginated mass that can be encapsulated and rarely calcified and heterogeneous hyperattenuating area within the tumor seen in necrosis or old hemorrhage. The MRI findings include; from hyperintense to mildly hypointense relative to the liver tissue on T1 weighted images. On T2 weighted images they are predominantly hyperintense relative to the liver, whereas in the presence of necrosis or hemorrhage they can be heterogeneous with hyper or hypoattenuating signal. The gold standard method for diagnosis of<unk>  is excision biopsy of the liver lesions either by surgery or laparoscopically. There is no specific medical therapy for the<unk> , wait & watch policy is recommended for<unk> s <5 cm following cessation of oral contraceptives. Annual followup with MRI or ultrasound is recommended until menopause. Surgical resection is the treatment of choice for<unk> s that are >5 cm in diameter, that increase in size, lesions with intra tumoral hemorrhage and male patients (irrespective of the<unk>  size). The radiofrequency ablation (RFA) and transcatheter arterial embolization (TAE) may be tried in patients who are poor candidates for surgery.
Hepatocellular adenoma
Fibrolamellar hepatocellular carcinoma
Focal fatty liver
Hepatic hemangioma
Hepatic cysts
Pancreatic islet cell carcinoma
Hepatocellular carcinoma
Fatty liver