Plexiform fibromyxoma of the duodenum – specific imaging findings and pathological analysis of a rare site: A case report

Rationale: Plexiform fibromyxoma (PF) is a rare, benign gastrointestinal mesenchymal tumor that rarely occurs in the duodenum and is easily confused with other tumors, leading to misdiagnosis. This article uses a rare duodenal case and combines imaging and pathological features to explore its diagnostic points to help improve the radiologists’ ability to recognize it. Patient concerns: A 51-year-old female patient was admitted to the hospital because of loss of appetite and fatigue for 1 week. Diagnoses: Imaging examination revealed a cystic solid mass in the duodenum, and enhanced scanning showed uneven progressive enhancement. The location and morphology of the mass changed during different examinations. Imaging diagnosis is considered a benign tumor of duodenal origin. The final diagnosis of duodenal PF was confirmed by histopathology and immunohistochemistry following surgical resection. Interventions: The patient underwent a radical pancreaticoduodenectomy. Outcomes: The patient had no intraoperative or postoperative complications and had no signs of recurrence during the 17-month and 5-year follow-up. Lessons: PF of the duodenum is a relatively rare tumor with specific imaging manifestations. Multiparameter magnetic resonance imaging examination can improve its diagnostic rate. We report a case of duodenal PF with complete CT and magnetic resonance imaging imaging examinations.