Metastatic gastric cancer from malignant fibrous histiocytoma: report of a case.

Metastatic gastric cancer originating from malignant fibrous histiocytoma (MFH) is rare. To our knowledge, only nine other cases have been reported. We report the case of a 75-year-old man who underwent a distal gastrectomy for advanced gastric carcinoma, 2 years after resection of an MFH from the left side of his back. We based our preliminary diagnosis of primary advanced gastric carcinoma on the results of a preoperative biopsy specimen, which suggested either poorly differentiated adenocarcinoma or nonepithelial cell-originating malignant disease-like lymphoma. The resected stomach contained a large ulcerative tumor in the antral section, which was positive for Kp-1 and S-100 by immunohistochemical staining, confirming a pathological diagnosis of metastatic MFH of the stomach. He died of recurrence in the mediastinal space 16 months after the gastrectomy. Our analysis of this and previous cases suggests that resection may be inappropriate for patients with gastric metastasis of MFH because of the extremely high malignant potential of this tumor.