focal nodular hyperplasia

hyperplasia

 [hi″per-pla´zhah]

abnormal increase in volume of a tissue or organ caused by the formation and growth of new normal cells. See also hypertrophy and proliferation. adj., adj hyperplas´tic.

benign prostatic hyperplasia benign prostatic hypertrophy.

cutaneous lymphoid hyperplasia a group of benign cutaneous disorders characterized by accumulations of large numbers of lymphocytes and histiocytes in the skin, which may occur as a reaction to insect bites, allergy hyposensitization injections, light, trauma, or a tattoo pigment or may be of unknown etiology.

focal nodular hyperplasia (FNH) a benign, usually asymptomatic tumor of the liver, occurring chiefly in women; it is a firm, nodular, highly vascular mass resembling cirrhosis, usually with a stellate fibrous core containing numerous small bile ducts, and having vessels lined by Kupffer cells.

nodular hyperplasia of the prostate benign prostatic hypertrophy.

Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

focal nodular hyperplasia

A relatively common (±1% of general population) benign lesion that develops spontaneously at age 20–30, predominantly in females, and not associated with oral contraceptives. If multiple (1/3 are multiple), it may be associated with vascular defects in other organs and brain (arteriovenous malformations).

Focal nodular hyperplasia
Primary FNH
• Congenital arterial malformation.
Secondary FNH
• Acquired vascular abnormalities;
• Cirrhosis;
• Haemangioma;
• Other neoplasms;
• Venous thrombosis.
Typical FNH
• Cirrhosis-like changes;
• Chronic biliary disease with bile duct loss;
• Adjacent space-occupying lesion.
Atypical FNH
• Large cell atypia;
• Mixed hyperplastic and adenomatous;
• No central scar, especially in lesions  < 1cm;
• No prominent ductular reaction;
• Telangiectatic.

Clinical findings
Generally asymptomatic; larger lesions may undergo infarction.

Imaging
Nodular lesion with central scar.

Management
Generally conservative management; indications for surgery uncertain.

Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.