Ectopic liver tissue mass in the thoracic cavity.

A case is reported in which a liver tissue mass, not connected to the liver, was discovered growing in the right thoracic cavity. This mass appeared following trauma sustained to the liver several years earlier, and was noted to increase slightly in size after its initial detection. After removal of the mass, which proved to be benign hyperplastic liver tissue, the patient did well and remained free of symptoms. It is suggested that during the episode of trauma or during the ensuing surgical repair, a fragment of liver tissue was introduced into the thoracic cavity, and that this fragment eventually developed into a hyperplastic nodular liver mass.