Prognosis of Solitary Fibrous Tumors: A Multicenter Study

• Published in: Annals of surgical oncology 2013-12, Vol.20 (13), p.4090-4095
• Main Authors: van Houdt, Winan J., Westerveld, Charlotte M. A., Vrijenhoek, Joyce E. P., van Gorp, Joost, van Coevorden, Frits, Verhoef, Cornelis, van Dalen, Thijs
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Biomarkers, Tumor - analysis; Bone and Soft Tissue Sarcomas; Female; Follow-Up Studies; Humans; Immunoenzyme Techniques; Male; Medicine; Medicine & Public Health; Middle Aged; Neoplasm Metastasis; Neoplasm Recurrence, Local - mortality; Neoplasm Recurrence, Local - pathology; Neoplasm Recurrence, Local - surgery; Neoplasm Staging; Oncology; Prognosis; Retrospective Studies; Soft Tissue Neoplasms - mortality; Soft Tissue Neoplasms - pathology; Soft Tissue Neoplasms - surgery; Solitary Fibrous Tumors - mortality; Solitary Fibrous Tumors - pathology; Solitary Fibrous Tumors - surgery; Surgery; Surgical Oncology; Survival Rate; Young Adult
• ISSN: 1068-9265; 1534-4681
• DOI: 10.1245/s10434-013-3242-9

Background Solitary fibrous tumors (SFTs) are rare mesenchymal tumors, and data regarding outcome and prognostic factors are scarce. We report the outcome and analysis of prognostic factors of a retrospective multicenter cohort study for patients treated for SFTs. Methods Retrospective analysis was performed of patients treated for SFTs between 1995 and 2012. Clinical and histopathological features were analyzed for prognostic value. Endpoints were set at local recurrence, metastasis formation, or death. Survival was analyzed using Kaplan–Meier and Cox proportional hazards analyses. Results A total of 81 patients underwent surgical resection of a SFT with curative intent. During follow-up, 21 patients developed distant metastases, while 18 patients developed local recurrence. The 5-year overall survival was 84 %. The local recurrence rate and the metastasis rate at 5 years were 29 and 34 %, respectively. Of all factors analyzed, positive resection margin significantly correlated with local recurrence [hazard ratio (HR) 4.8; 95 % confidence interval (95 % CI) 1.5–14.9]. Tumor size >10 cm (HR 4.4; 95 % CI 1.7–11.5) and high mitosis rate (HR 3.3; 95 % CI 1.06–10.3) significantly correlated with higher incidence of metastases. The combination of tumors >10 cm and high mitosis rate significantly correlated with higher incidence of metastases (HR 4.8; 95 % CI 1.4–16.2) and showed a trend toward worse overall survival (HR 5.7; 95 % CI 0.95–34.7). Conclusions A substantial portion of patients with a SFT developed local recurrence or metastases. Local recurrence is significantly higher in patients with positive resection margins; metastasis frequency is significantly higher in patients with tumors >10 cm and tumors with a high mitosis rate.