Hibernoma is a benign soft-tissue tumor, derived from the brown fat, t
hat often presents as a painless, slow-growing mass. About 100 cases o
f hibernomas have been reported in the world literature. Seven cases o
f intrathoracic hibernoma are reported, of which only 1 was located in
the mediastinal region. That tumor was an intramediastinal hibernoma
with a cervicomediastinal location, which was excised through an exten
ded left supraclavicular incision without the necessity to perform a s
ternotomy. No recurrence was evident after 18 months. (C) 1997 by The
Society of Thoracic Surgeons.