Liver Neoplasms, Benign

Key Features

• Cavernous hemangioma

  • Most common benign hepatic neoplasm

  • Often found incidentally on ultrasonography or CT

  • Hormonal therapy may cause these lesions to enlarge

• Hepatocellular adenoma

  • Most common in women in the third and fourth decades of life

  • Usually caused by oral contraceptives

• Focal nodular hyperplasia

  • Occurs at all ages and in both sexes

  • Probably not caused by oral contraceptives

Clinical Findings

• Hepatocellular adenoma may present with acute abdominal pain if tumor undergoes necrosis or hemorrhage

• Focal nodular hyperplasia is often asymptomatic

• The only physical finding in both lesions is a palpable abdominal mass in a few cases

Diagnosis

• Cavernous hemangioma

  • Must be differentiated from other liver lesions, usually by MRI

  • Rarely, fine-needle biopsy is needed

• Hepatocellular adenoma

  • A hypovascular tumor

  • A cold defect on liver CT scan

• Focal nodular hyperplasia

  • Appears as a hypervascular mass, occasionally with a central hypodense "stellate" scar on contrast-enhanced ultrasonography, CT, or MRI

  • Consists of hyperplastic units of hepatocytes that stain positively for glutamine synthetase

• Contrast-enhanced ultrasonography, arterial-phase helical CT and especially multiphase dynamic MRI can distinguish a hepatocellular adenoma from focal nodular hyperplasia in 80–90% of cases

• In both focal nodular hyperplasia and hepatocellular adenoma, the liver function is usually normal

Treatment

• Surgical resection of cavernous hemangiomas is infrequently necessary but may be required

  • For abdominal pain or rapid enlargement

  • To exclude malignancy

  • To treat Kasabach-Merritt syndrome (consumptive coagulopathy complicating a hemangioendothelioma or rapidly growing hemangioma, usually in infants)

• Focal nodular hyperplasia

  • Resection done only in the symptomatic patient

  • Annual ultrasonography for 2–3 years is advised in affected women who continue taking oral contraceptives to make sure the lesion is not enlarging

  • Prognosis is excellent

• Hepatocellular adenoma

  • If asymptomatic, regression of hepatocellular adenomas may follow cessation of oral contraceptives

  • However, adenomas may undergo bleeding, necrosis, and rupture

  • Transarterial embolization is the initial treatment for adenomas complicated by hemorrhage

  • Resection is advised in all patients in whom the tumor causes symptoms or measures > 5 cm in diameter, even in the absence of symptoms

  • Resection is also recommended even for an adenoma measuring < 5 cm in diameter if a beta-catenin gene mutation is present in a biopsy sample

  • In selected cases, laparoscopic resection or percutaneous radiofrequency ablation may be feasible

  • Rarely, liver transplantation is necessary