Etiology analysis and computed tomography imaging of a tonsillar inflammatory myofibroblastic tumor: report of an immunocompetent patient and brief review

Abstract

Objectives: The etiology of Inflammatory myofibroblastic tumor(IMT) is contentious. In this study, we used computed tomography (CT) to examine tonsillar IMT and further analyzed the etiology of this entity.

Methodology: We presented CT features of left tonsillar IMT and reviewed the English-language literature published between 1984 and 2011.

Results: To our knowledge, there are only six published cases of tonsillar IMT including the present case. Two patients were asymptomatic at initial presentation. Two patients were taking immunosuppressants, and one was pregnant and in an immunomodulated state. CT of our patient revealed a 2.6 × 1.8 cm irregular soft tissue mass between the left tonsil and the base of the tongue. It did not invade surrounding structures and was not enhanced on contrast-enhanced imaging.

Conclusions: Tonsillar IMT may be a benign tumor. We suggest that preoperative recognition of tonsillar IMT by CT may be important to avoid unnecessary expanded surgery.

Figure 1

CT of pharynx showed that a 2.6 cm × 1.8 cm irregular soft tissue mass between the left tonsil and the base of the tongue(A), with no enhanced on contrast-enhanced imaging(B).C: The mass and left tonsil were excised completely. D: surgical specimen.

Figure 2

Routine pathological examination demonstrated that the tumour was composed of short spindle cells arranged as weaving. The spindle cells in some areas were rich and some cells were atypia and mitotic, mixed with inflammatory cells such as lymphocytes and plasma cells arranged as cluster(A:HE × 40). Immunohistochemical analysis was positive for the expression of desmin(B: EliVision × 40) and AKT(3 C: EliVision × 40), focal positive for S-100 protein(D: EliVision × 40).