A case of primary gastric undifferentiated high-grade pleomorphic sarcoma diagnosed with chief complaint of fever: a case report and literature review

Abstract

Background: Undifferentiated high-grade pleomorphic sarcoma in gastrointestinal tract is extremely rare, and its prognosis is poor.

Case presentation: An 82-year-old man visited a previous hospital complaining of fever, general fatigue, and shaking chill, for which he received antibiotics therapy. As the fever continued, he was referred to our hospital, where computed tomography and upper gastrointestinal endoscopy showed a 6-cm gastric tumor. A preoperative biopsy was consistent with a malignant mesenchymal tumor, but could not provide a definitive pathological diagnosis nor prove a cause-and-effect relationship between the chief complaint and the gastric tumor. The gastric tumor had grown to 8 cm in diameter within a month so we performed a partial gastrectomy. The pathological postoperative diagnosis was undifferentiated high-grade pleomorphic sarcoma that produced granulocyte colony-stimulating factor. The patient's fever quickly improved, and he showed a good postoperative course.

Conclusions: We herein report a case of rapidly growing, undifferentiated, high-grade pleomorphic gastric sarcoma, which presented as a chief complaint of fever.

Keywords: Fever; Granulocyte colony-stimulating factor (G-CSF); Stomach; Undifferentiated high-grade pleomorphic sarcoma.

Fig. 1

Abdominal computed tomography (CT) showed a 6-cm gastric tumor in early August (a) that had enlarged to 8 cm in diameter by early September (b)

Fig. 2

Gastrointestinal endoscopy in early August showed a 6-cm pedunculated tumor on the greater curvature in the gastric body (thick arrow); nearby, a 2-cm sub-pedunculated tumor was also observed (thin arrow)

Fig. 3

Upper gastrointestinal fluoroscopy in early August showed a 7-cm sub-pedunculated raised lesion (a) with a 12-mm attachment (b) on the greater curvature of the upper gastric body

Fig. 4

Gross findings of the tumors showed a pedunculated multinodular tumor (a) and a polypoid tumor (b). A gray-white tumor with focal hemorrhage was observed by cut surface of the large one (c). The tumor was observed very close to the surgical margin

Fig. 5

Microscopic findings showed proliferation of atypical spindle-shaped tumor cells arranged in sheets and irregular fascicles (a). Mitotic figures were frequently encountered (arrows, 20–25/10 HPF) and mild infiltration of lymphoplasmacytoid cells was noted (b). The large pleomorphic and bizarre tumor cells were also observed (c). Immunohistochemically, the tumor cells were positive for α1-antichymotrypsin (d), p-53 (e), and G-CSF (f)