Plexiform Fibromyxoma Of The Stomach: A Case Report And Review Of The Literature

Background: Plexiform fibromyxoma (PF) is a recently described rare type of mesenchymal tumor of the stomach that is characterized by a peculiar plexiform growth pattern, myxoid stroma, and spindle-shaped myofibroblastic cells. PFs are mainly located in the antrum of the stomach, and are treated by distal or partial gastrectomy. This study reports a rare case of PF that occurred in the body of the stomach. A review of PF cases reported in both English and Chinese literature is also provided. Case report: A 52-year-old Chinese female presented with 1-month of intermittent upper abdominal pain. Gastroscopy and computed tomography (CT) revealed a submucosal mass with a small overlying mucosal ulceration in the gastric wall at the mid greater curvature of the stomach. Intraoperative rapid frozen section suggested the benign nature of the tumor and the patient underwent gastroscope-assisted laparoscopic wedge resection. Pathological examination of the resected specimen revealed plexiform growth of spindle cells without nuclear atypia and abundant myxoid capillary-rich extracellular matrix. The spindle-shaped cells diffusely expressed smooth muscle actin (SMA) and focally expressed CD10, but were negative for CD34, CD117, DOG-1, P53, and KI-67 (index 1%). The 10-month postoperative course was favorable without any complications or disease recurrence. Conclusion: Although PF closely resembles gastrointestinal stromal tumors (GIST) and other myxoid/fibromyxoid tumors of the stomach, it has distinct pathological and/or immunochemical features, as well as clinical management. Further clinical research is needed to elucidate the clinical course and to develop a standard treatment strategy.