Clinical management of metastatic gastric tumors: a case report of right popliteal leiomyosarcoma metastasizing to the stomach and literature review

Gastric metastases are rare, accounting for only 0.2%–0.7% of gastric malignancies. Gastric metastasis from primary popliteal fossa leiomyosarcoma (LMS) has not been previously reported. We report a 60-year-old female who presented with hematemesis and severe anemia, with a past medical history of right popliteal fossa LMS resection. Imaging and endoscopy revealed a bleeding nodular lesion in the gastric body. Pathology and immunohistochemistry (SMA+/Desmin+, CD117–/DOG-1–) confirmed metastatic LMS to the stomach, with suspected pancreatic and bone metastases. The patient underwent emergency embolization for active bleeding, followed by laparoscopic partial gastrectomy and systemic chemotherapy. At the 9-month follow-up, she remained in good general condition. This case highlights that in patients with a history of malignancy presenting with gastrointestinal bleeding, gastric metastasis should be considered, and multidisciplinary management combined with surgery and systemic therapy can achieve favorable outcomes.