Radiological and histopathological features of hepatic inflammatory myofibroblastic tumour: analysis of 10 cases

To evaluate the radiological and histopathological features of hepatic inflammatory myofibroblastic tumours (IMTs), and improve the understanding of this tumour.

A retrospective analysis of radiological and histopathological features of 10 cases of IMT was carried out from May 2003 to September 2011 at the Second Xiangya Hospital of Central South University.

Ten cases (five male and five female patients; age range 4-68 years) were enrolled. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed that the lesions were regular, hypodense or hypointense (T1WI) masses with well-defined borders (n = 8) or ill-defined borders (n = 2). The maximum diameter ranged from 3.1-13.4 cm (mean = 6 cm). The masses showed homogeneous (n = 8) or inhomogeneous (n = 2) density. Contrast-enhanced CT and MRI showed the lesions were mildly, irregularly enhanced (n = 7) or not enhanced (n = 2) in the arterial phase and markedly enhanced in the portal venous phase or delayed phase. Hepatic arteriography revealed that the lesions were hypovascular and had a well-defined border. One patient had lung metastasis with obvious arterial phase enhancement. None of the patients had a history of hepatitis, cirrhosis, or enlarged lymph nodes. Pathology showed that the gross appearance of the tumours was smooth. The tumour cells comprised spindle-shaped fibroblast and myofibroblast cells with abundant inflammatory cells. Immunohistochemistry showed that most were positive for vimentin, smooth muscle actin (SMA), and CD68, but negative for CD34, anaplastic lymphoma kinase (ALK), S-100, and CD117.

Radiological features of IMT have some characteristics of an intermediate-grade malignant tumour. However, imaging alone cannot be used to diagnose IMT. Therefore, histopathological examination is necessary for confirmation.