Clinical, endoscopic and pathological features of gastrointestinal and mesenteric reactive nodular fibrous pseudotumor / 中华消化内镜杂志

ABSTRACT

Objective To study the clinical, endoscopic and pathological features of gastrointestinal and mesenteric reactive nodular fibrous pseudotumor (RNFPT). Methods A retrospective analysis was conducted on data of 24 RNFPT patients in Nanjing Drum Tower Hospital admitted from October 2008 to June 2016. The clinical, endoscopic, pathological and immunohistochemical characteristics were analyzed. Results Among the 24 patients, 16 complained about discomfort in the upper abdomen and 10 had a history of surgery or trauma. Twenty-one had isolated masses and 3 had multiple masses, with diameter of 0. 5-4. 0 cm. Endoscopically, the tumors were mainly hard submucosal masses with broad base, and smooth surface with no mucosal bridge. Seventeen patients underwent endoscopic ultrasonography, which showed low echoes in lesions and nonuniform echoes partly. Among them, 13 lesions derived from muscularis, 4 others from submucosa. Microscopically, the tumors had clear boundary with no envelope, and most areas showed disorderly arranged spindle cells and extensively collagenous degenerated mesenchyma. The spindle cells had shuttle fibroblast-like morphology and elongated nucleus with no visible necrosis or mitosis. Inflammatory cells scattered between the tumor cells, and lymphoid follicles and calcium deposition could be seen in local areas. Immunohistochemically, SMA was focally positive in 7 cases and only 4 cases expressed CD117 scattered. Desmin, Dog-1, CD34, ALK-1 and S-100 were all negative, and Ki-67 proliferation index was lower than 1％. Conclusion RNFPT has diverse clinical manifestations, with a good prognosis and unlikely recurrences, and should be distinguished from spindle cell tumors.