Malignant Solitary Fibrous Tumor of the Abdominal Wall Mimicking a Hepatic Tumor

A 70-year-old woman visited our hospital with a complaint of discomfort in the right upper abdominal quadrant. CT and US revealed a tumor in the lateral segment. This tumor was diagnosed as a hemangioma, and follow-up was planned. Nine months later, follow-up CT revealed growth of the main tumor and a new hepatic lesion in the median segment. Hepatic malignancies were strongly suspected and were resected. The pathological diagnosis was a malignant fat-forming solitary fibrous tumor (SFT) of the abdominal wall. The patient died 27 months later due to hepatic and pulmonary recurrences. SFT is an uncommon neoplasm of mesenchymal origin that usually arises from the pleura. SFT of the abdominal wall is extremely rare, and to the best of our knowledge, only 13 other cases have been reported in the international literature. All 13 cases were benign. Here, we report the first case of a malignant SFT arising from the abdominal wall with a review of the relevant literature.