[Inflammatory myofibroblastic tumor of the larynx]

Inflammatory myofibroblastic tumor (IMT) of the larynx is a rare borderline lesion composed of myofibroblastic and inflammatory cells.

We presented a case of 77-year-old male with hoarseness for about three months. Laryngoscopy showed a polypoid tumor originated from the anterior commissure with glottic projection. Grossly, the tumor was 22 x 15 mm, whitish, oval nodus with firm consistency. Histologically, the lesion was composed of spindled to stellate cells arranged in a fascicular to storiform pattern and inflammatory cells: lymphocytes, histiocytes, plasma cells and neutrophils. The stroma was fibromyxoid and collagenous. Immunohistochemically, tumor cells showed strong positivity for actin and vimentin and negativity for cytokeratin, CD34, S100 and desmin. The proliferation (Ki67) was less than 10%.

Inflammatory myofibroblastic tumor may be mistaken as a malignancy and the differential diagnosis can be difficult without immunohistochemistry. It is critical to recognize this uncommon entity to avoid unnecessary aggressive treatment.