Oral contraceptive-dependent growth of focal nodular hyperplasia.

A 22 year old woman was incidentally found to have a hepatic small haemangioma-like mass, measuring 1.4 cm in diameter, by an ultrasonographic examination. The mass demonstrated no change in size or appearance for 6 months until the patient began to take oral contraceptives. Eventually, the mass increased to 2.0 cm in diameter after using oral contraceptives for 6 months. A histological examination suggested the mass to be typical focal nodular hyperplasia, and not hepatic adenoma. There was no further change in either size or appearance in the ensuing 1 year after the discontinuation of oral contraceptives.