BACKGROUND: Inflammatory myofibroblastic tumors (IMTs) are scarce tumors with discrete immunohistochemical and molecular attributes which are not related to a particular location. There are different reports about the intrinsic nature of these tumors as benign to possibly malignant.

CASE REPORT: Here we report the case of a 68-year-old man referred to the Internal Medicine Department of Razi Hospital in Rasht (a city in the north of Iran) due to right lower quadrant (RLQ) discomfort with no specific symptoms. Colonoscopy revealed a mass-like lesion. Polymorphonuclear cells (PMNCs) admixed by some eosinophils were demonstrated histopathologically. Immunohistochemical evaluation was positive for vimentin, CD34, smooth muscle actin, and ALK, and negative for CD117 and desmin. The tumor was successfully removed by surgery with no chemotherapy. No recurrence was reported.

CONCLUSIONS: We have performed surgical excision of the mass with no chemotherapy and no recurrence. Although recurrence is reported to be low, we recommend long-term follow-up after surgery.

Keywords: Biological Markers, Colonoscopy, Gastrointestinal tract