Serum β-hCG as an Indicator of Recurrence After the Complete Resection of a Malignant Solitary Fibrous Tumor of the Pleura

In solitary fibrous tumors (SFTs) of the pleura, malignant SFTs are uncommon. Although SFTs are known to cause paraneoplastic syndromes through the production of insulin-like growth factor, to the best of our knowledge, the production of beta-human chorionic gonadotropin (β-hCG) has been reported only in 1 case involving a patient with a benign SFT. We herein report the first case of the elevation of β-hCG serum levels associated with a malignant SFT in which the β-hCG serum level became a useful indicator of recurrence after the complete resection of the primary mediastinal lesion.