Solitary fibrous tumors of the pleura: immunohistochemical analysis and evaluation of prognostic factors after surgical treatment

Background and Objectives: Solitary fibrous tumors of the pleura (SFTP) are rareneoplasms with unusual histological and clinical features. Although surgery is thetreatment of choice for SFTP, tumor recurrence may occur after complete resection,even in tumors with benign histological features. The aim of the study was to identifythe clinical and pathological features of SFTP that are associated with a higher risk ofrecurrence after surgical treatment.Methods: From May 1995 to September 2002, 18 patients (10 female, 8 male; meanage 58 years) with SFTP underwent complete surgical treatment at our department.Mean follow-up was 61 months. Mean tumor size was 10 cm. The tumors werepedunculated in 10 patients and sessile in 8. Histological features were benign in 16patients and malignant in 2.Results: Five-year disease-free survival was 80%. A higher incidence of tumorrecurrence was observed when SFTP originated from the parietal pleura, hadmalignant histological features and a lower expression of progesterone receptors(P<0.05).Conclusions: Clinical and pathological characteristics, such as malignant histology,sessile morphology, and a lower expression of progesterone receptors identify SFTPwith a higher risk of recurrence after surgery, and which thus require strict follow-up.