Recurrent solitary fibrous tumor of the pleura with malignan
Solitary fibrous tumors (SFT) of the pleura originate from the visceral pleura. Most of the SFTs are benign tumors, malignant tumors only account for 12%. Although most tumors are considered histologically benign, locally aggressive behavior with repeated recurrences and distant metastasis has been observed in some cases.

Doctors report a rare case of recurrent solitary fibrous tumor (SFT) of the pleura with suspicious malignant transformation.

A 78-year-old man had undergone prior surgical resection of the primary and recurrent SFT tumors at 11 and 2 years before the current presentation. Although his primary tumor had a round shape and did not show invasive growth, the current recurrent tumor extended through the neural foramen and had an osteoclastic progression into the thoracic spine.

A computed tomography (CT) guided needle biopsy was performed and the pathological diagnosis of the tumor was confirmed as the recurrence of SFT. Immunohistochemically, the MIB-1 proliferation index (Ki-67) of the primary tumor and the current tumor was 1.74 and 30.00%, respectively.

These clinical and immunohistochemical findings were strongly suspected the malignant transformation of SFT from benign. He was treated with radiotherapy, and a response was observed.

Doctors report a case of immunohistochemically confirmed malignant transformation of recurrent pleural SFT. Furthermore, this recurrent tumor had a response to radiotherapy.

Journal of Surgical Case Reports