Inflammatory Myofibroblastic Tumor of the Gallbladder Mimicking Malignancy: A Case Report and Literature Review

Inflammatory myofibroblastic tumor (IMT) of the gallbladder is an exceptionally rare benign tumor, often misdiagnosed as malignancy due to its radiologic and clinical features. Fewer than ten cases have been reported in the literature. IMT is characterized histologically by a proliferation of myofibroblastic spindle cells with inflammatory cell infiltration. We report the case of a 71-year-old male presenting with upper abdominal pain for 1 month. Imaging revealed a hetero-echoic mass replacing the gallbladder and invading the adjacent liver, initially suspected to be gallbladder carcinoma. The patient underwent exploratory laparotomy, extended cholecystectomy, and Roux-en-Y hepaticojejunostomy. Histopathology confirmed the diagnosis of inflammatory myofibroblastic tumor of the gallbladder. The postoperative course was uneventful, and the patient remains recurrence-free at 2 years follow-up. Gallbladder IMTs are rare entities that clinically and radiologically mimic carcinoma. Surgical resection remains the mainstay for diagnosis and treatment. Despite being histologically benign, IMTs have potential for local invasion and recurrence, warranting long-term follow-up.