Perioperative Decision-Making for a Solitary Fibrous Tumor of the Pleura: Lessons from Two Cases and Current Evidence

Background and Clinical Significance: Solitary fibrous tumor of the pleura (SFTP), a rare mesenchymal neoplasm (<5% of pleural tumors), is often asymptomatic and incidentally detected. Preoperative differentiation between benign and malignant forms remains challenging, with 10-20% of lesions showing malignant behavior despite benign imaging. The role of conservative "watch-and-wait" versus early resection in small, asymptomatic cases is debated, prompting the need for structured perioperative decision-making based on imaging, pathology, and risk models. Case Presentation: We report two surgically resected SFTP cases. Case 1 involved an 8 cm giant pedunculated benign tumor managed by open thoracotomy (negative margins, mitotic count: 1.5-2.0/10 high-power fields, necrosis < 10%), with the patient remaining recurrence-free at 4 years postoperatively. Case 2 involved a 5.3 cm pedunculated benign tumor (initially 4.8 cm, which grew during a 2-year observation) excised via a minimally invasive technique (mitotic count: 0.5-1.5/10 high-power fields, necrosis < 10%), showing no recurrence over 6 months. In both cases, safe R0 resection was achieved through clinicoradiologic assessment and appropriate surgical technique selection. Both tumors were classified as benign and low risk by the England, Tapias, and modified Demicco models and are undergoing a tailored follow-up protocol. Conclusions: These two cases illustrate the feasibility of en bloc R0 resection in operable SFTP, despite interval growth observed in Case 2. Combined with literature evidence, early en bloc R0 resection appears to be preferable to prolonged observation for operable SFTP, balancing the risks of unpredictable growth, malignant transformation, and recurrence-even in histologically benign tumors (up to 6.3%)-against potential surgical morbidity. Tailored preoperative planning appears beneficial, complemented by pathology-based risk models for postoperative stratification and risk-adapted surveillance.