Abstract
Solitary fibrous tumor of the pleura (SFTP) is a rare mesenchymal tumor, making up a small fraction of primary pleural tumors. It is typically benign but can display malignant features. This case presents a 59-year-old patient with a giant malignant SFTP located in the right posterior inferior mediastinum, which caused significant compression of adjacent structures, including the lung, heart, and esophagus. The patient initially presented with dyspnea, chest pain, and weight loss. Imaging studies revealed a voluminous mass with heterogeneous characteristics, calcifications, and pleural effusion, while biopsy and histopathological analysis confirmed a mesenchymal proliferation consistent with a solitary fibrous tumor. Despite partial resection, due to the tumor's size and extensive adhesions, complete removal was not feasible. Postoperative histological findings revealed features indicative of malignancy, including a high mitotic index and slight nuclear atypia. The patient declined adjuvant chemotherapy and radiotherapy, and experienced recurrence within four months. Despite the lack of chemosensitivity, the tumor progressed locally, and the patient's clinical condition worsened. This case highlights the challenges in diagnosing and managing malignant SFTPs, emphasizing the importance of individualized treatment plans and the necessity for long-term follow-up due to the risk of recurrence and poor prognosis following incomplete resection.