Demicco EG, et al. - Via clinicopathologic data evaluated on an independent cohort from two large hospitals of 303 patients with extra-meningeal solitary fibrous tumors (SFT, fibroblastic mesenchymal tumors with a 10-30% metastatic rate), the researchers intended to assess the several risk models that were proposed for extra-meningeal SFT. A 13% risk of metastasis at 5 years and 16% at 10 years was observed in the independent cohort. Aggressive behavior in solitary fibrous tumors, with the modified Demicco and Salas OS risk models that portrayed the best correlation with metastasis and recurrence-free survival, could be accurately predicted through multivariate risk models which included mitotic rate and patient age.