Aggressive undifferentiated pleomorphic sarcoma of the stomach involving long-term survival: A case report and literature review

Abstract

Primary gastric undifferentiated pleomorphic sarcoma (UPS) is a rare disease with insufficient long-term follow-up data. In the present study, a 70-year-old male complained of abdominal fullness and visited our hospital. Abdominal computed tomography revealed a large tumor in the upper part of the stomach, which was accompanied by smaller tumors in the small intestinal mesentery. An endoscopic ultrasound-guided fine-needle biopsy examination of the gastric tumor revealed features of pleomorphic sarcoma and high-grade spindle-shaped cells. Total gastrectomy was performed on the primary tumor, together with combined resection of the small intestine for the metastatic tumors. However, the tumor recurred in the mesentery of the sigmoid colon 6 months after the operation. A second operation was performed to resect the recurrent tumor. Since the second surgical procedure, the patient has remained free from recurrence for >7 years. Although the prognosis of abdominal UPS was considered to be poor, even after curative surgery, the present case experienced a long-term survival of gastric UPS after undergoing surgical resection alone.

Keywords: gastric sarcoma; metastasis; undifferentiated pleomorphic sarcoma.

Figure 1.

Contrast-enhanced abdominal computerized tomography revealed a 14-cm oval tumor in the stomach and 10-cm tumors in the mesentery of the small intestine. The tumor in the stomach was encapsulated and contained a central low-density region.

Figure 2.

Magnetic resonance imaging revealed that the tumor exhibited low signal intensity on T1-weighted images and high signal intensity on T2-weighted images. (A) T1-weighted image, (B) T2-weighted image.

Figure 3.

Upper gastrointestinal endoscopy revealed a submucosal tumor in the cardia of the stomach. EUS showed a hypoechoic mass originating from the submucosa. (A) Upper gastrointestinal endoscopic imaging, (B) EUS imaging.

Figure 4.

(A) Gross findings of the resected gastric specimen. The tumor was solid and lobulated and necrosis was evident in the center of the tumor. (B) Gross findings of the resected gastric specimen. The tumor arose from the submucosal layer. (C) The tumors were composed of atypical irregularly arranged spindle-shaped cells with large pleomorphic or bizarre nuclei.