A Case of Mammary-Type Myofibroblastoma Occurring in the Inguinal Region.

Mammary-type myofibroblastoma (MTMF) is a rare benign tumor of mesenchymal cells that occurs in the inguinal region, abdominal wall, buttocks, back, and vaginal wall. When a soft tissue mass develops in the inguinal region, there may be a risk of misdiagnosing it as an inguinal hernia, especially if it is asymptomatic. We report a rare case of mammary-type myofibroblastoma occurring in the inguinal region. The patient was a 40-year-old male who noticed swelling in the right inguinal region two years prior and consulted a nearby medical clinic. He was diagnosed with a right inguinal hernia and referred to our hospital. On physical examination, a protrusion was observed in the right inguinal region, and due to difficulty in reduction, emergency surgery was performed, suspecting intestinal incarceration. Intraoperatively, no inguinal hernia was found, but a mobile yellowish mass was identified. There were no malignant features, and the mass was excised. The pathological examination revealed mammary-type myofibroblastoma. When we examine a patient with a complaint of inguinal swelling, it is important to consider not only inguinal hernia but also other conditions such as soft tissue tumors.