Plexiform fibromyxoma of the lesser curvature of the stomach in a 16-year-old adolescent: A case report and literature review.

Gastric plexiform fibromyxoma (PF) is a rare mesenchymal tumor, with ~150 cases reported worldwide, predominantly occurring in the gastric antrum of adults. The present study describes a case of isolated PF in the lesser curvature of the stomach in a 16-year-old male patient. As confirmed by various multi-dimensional analyses of clinical, imaging and pathological data, the unique features of the case included its adolescent onset (only 12 cases of patients ≤18 years old have been reported globally) and the solitary localization in the lesser curvature of the stomach, with no previously documented cases. The patient presented with abdominal pain. A computed tomography scan revealed a solid intramural gastric mass with progressive enhancement. Postoperative pathology combined with immunohistochemistry (vimentin+, smooth muscle actin partially+, CD10+ and CD117/discovered on GIST-1-) confirmed the diagnosis. No recurrence was observed during the 12-month follow-up. The present case expands the clinical spectrum of PF and emphasizes the value of multimodal diagnosis for tumors in rare locations.