This is a case of a rare hepatic mesenchymal tumor called a solitary fibrous tumor.

The imaging features are not specific and a prospective diagnosis is not realistic. The point of this case is really the diagnostic reasoning to generate a reasonable differential for the mass.

On the precontrast images, a number of masses, benign and malignant are possible. One should always remember that, although less common, HCC can occur in a liver not affected by cirrhosis (although usually in this situation, there is an occult history of chronic hepatitis B infection) ².

The postcontrast dynamic sequence, however, has a more benign enhancement pattern. Given the well-circumscribed heterogeneously solid appearance of the mass, more rare fibrous tumors could be entertained on the differential

• hepatic leiomyoma / leiomyosarcoma
• inflammatory myofibroblastic tumor
• solitary fibrous tumor of the liver
• hepatic schwannoma / nerve sheath tumor

Given the rarity of these lesions, however, a biopsy is still necessary for a diagnosis. An atypical presentation of a common malignant lesion is still more typical than these rare lesions.