Hibernoma, an uncommon tumor as a differential diagnosis of liposarcoma of the thigh.

Hibernomas are benign tumors derived from brown fat of hibernating animals and of human infants. The pathogenesis and malignant potential of hibernomas remain unclear. They occur generally in adults with a peak incidence in the third decade and with a predominance in women. However, the lesions may have an heterogeneous presentation that may mimic liposarcomas on MRI. Our report presents a case of hibernoma of the thigh whose the diagnosis initially suggested that it was a mixed liposarcoma with myxoid and well differentiated components.