Two cases of primary malignant fibrous histiocytoma of the liver: immunohistochemical expression of ezrin and its relationship with prognosis.

Malignant fibrous histiocytoma (MFH) as soft tissue sarcoma would not be especially noteworthy, but primary hepatic MFH reports are extremely rare. Herein, we report ezrin expression in tumor tissues from two primary hepatic MFH cases with different prognoses. Cases 1 and 2 were both women, ages 45 and 70 years, respectively. Case 1 had an 11 x 10 cm liver tumor in segment (S) 3, and case 2 had two liver tumors, 12 x 8 cm in S5 and 10 x 7 cm in S8. Neither had any other systemic tumors. Cases 1 and 2 survived for two year and ten months and for eight and a half months, respectively, after the initial tumor resection. Microscopically, the tumors of these two cases were similar and showed proliferation of atypical cells, including spindle, pleomorphic and multi-nucleated giant cells arranged in storiform, sheet and/or fascicle patterns, with scattered foci of inflammatory cells, indicating MFH. Ezrin expression in tumor tissue from case 1 was sparse, whereas that of case 2 showed strong ezrin expression in many tumor cells. The present results indicate ezrin immunoreactivity in primary hepatic MFH to correlate possible with prognosis, which is consistent with reports on some other types of malignancies.