Hepatic sinusoidal ectasia.

Oral contraceptive-associated sinusoidal ectasia is a rare lesion of unknown pathogenesis. We describe the case of a 31-year-old woman who had used oral contraceptives for 10 years and was found to have abnormal liver function tests on "routine" examination. A single 9 x 5 x 4 cm hypervascular lesion was demonstrated radiographically. The hepatic immuno-diacetic acid and liver-spleen scans were normal. One subcapsular lesion was identified in the resected right hepatic lobe; it was characterized by focal marked dilatation of the sinusoidal spaces associated with rare hepatocyte necrosis and early intrasinusoidal fibrosis. The subcapsular location and the vascular nature of this wedge-shaped lesion suggest it may represent the telangiectatic precursor of a centrally scarred focal nodular hyperplasia.