Nested stromal-epithelial tumor (NSET) of the liver: a case report of an extremely rare tumor.

Malignant mixed tumors of the liver in adults are extremely rare. To our knowledge, only a few cases have been reported in the literature. Nested stromal-epithelial tumors (NSET) of the liver are characterized by non-hepatocytic, non-biliary tumors with nests of epithelial and spindle cells, an associated myofibroblastic stroma, as well as variable calcifications and ossifications. We report a case of NSET of the liver affecting a young woman and provide detailed histological and clinical follow-up data, adding an additional case of this extremely rare pathology to the literature.