Oral inflammatory myofibroblastic tumor: case report and review of literature

Abstract

Inflammatory myofibroblastic tumor (IMT) is a rarely described tumor of unknown etiology and pathogenesis. It occurs primarily in the lungs, but has occurred in other extra-pulmonary sites. Histologically these lesions appear as an inflammatory infiltrate within a variably myofibrotic background. Current evidence shows that inflammatory myofibroblastic tumors are neoplastic processes resulting from chromosomal translocations that often cause an overexpression of ALK kinase, which is often assessed using immunohistochemical studies. Currently, the biological behavior of oral inflammatory myofibroblastic tumor is still uncertain. This article describes the clinical, histological, and operative features of a case of IMT of the oral cavity.

Keywords: Inflammatory myofibroblastic tumor; inflammatory pseudotumor; oral cavity..

Fig. (1)

Intraoral photograph at the initial examination. A 15-mm painless nodule was observed on anterior maxillary ginigiva.

Fig. (2)

A,B) Low and high power views of the lesion, showing a proliferation spindle cells admixed with numerous chronic inflammatory cells (neutrophils, lymphocytes, macrophages and plasma cells) in a fibrous and myxoid background (hematoxylin and eosin, original magnification X4 and X20). C) Low power view of the immunohistochemical expression for smooth muscle actin showing positive spindle cells (original magnification X10). D) Immunohistochemical expression of ALK was positive (original magnification X10). E) Immunohistochemical expression of CD-68 showing positivity of histocytes (original magnification X10).

Fig. (3)

Postoperative follow up after four months showing complete healing of the gingiva and no signs of recurrence. Note closure of diastema with veneer.