In a pig carcass a cylindrical mass was observed in the mediastinum measuring roughly 30x10cm, with a brownish color and a hard consistency. No lesions were noticed on the other viscera. Inspectors suspected of a neoplastic proliferation.

Histopathological study reveals that the mass consists of hepatic parenchyma with marked fibrosis. It is therefore a herniation of a hepatic lobe, through the diaphragm to the thoracic cavity. Since the hernia canal was sealed, the respiratory function was not compromised and the animal was able to reach slaughter age.

Large mass located in the mediastinum (arrowhead).

Detail of the mass section.

The nodule, once extracted from the thoracic cavity and sectioned sagitalment.