Histology has not been accepted as a valid predictor of the biological behavior of extra-meningeal solitary fibrous tumors (SFTs). Based on the lack of a histologic grading system, a risk stratification model is accepted by the WHO to predict the risk of metastasis; however, the model shows some limitations to predict the aggressive behavior of a low-risk/benign-appearing tumor. We conducted a retrospective study based on medical records of 51 primary extra-meningeal SFT patients treated surgically with a median follow-up of 60 months. Tumor size (p = 0.001), mitotic activity (p = 0.003), and cellular variants (p = 0.001) were statistically associated with the development of distant metastases. In cox regression analysis for metastasis outcome, a one-centimeter increment in tumor size enhanced the expected metastasis hazard by 21% during the follow-up time (HR = 1.21, CI 95% (1.08–1.35)), and each increase in the number of mitotic figures escalated the expected hazard of metastasis by 20% (HR = 1.2, CI 95% (1.06–1.34)). Recurrent SFTs presented with higher mitotic activity and increased the likelihood of distant metastasis (p = 0.003, HR = 12.68, CI 95% (2.31–69.5)). All SFTs with focal dedifferentiation developed metastases during follow-up. Our findings also revealed that assembling risk models based on a diagnostic biopsy underestimated the probability of developing metastasis in extra-meningeal SFTs.

Background: To deal with health problems, using an approach, based on prevention perspective, consist of different types of prevention, can be a proper way to manage the health problems such as surgical site infections (SSIs). Objective: Introducing an action plan from the perspective of "prevention" for dealing with surgical site infections (SSIs). Evidence Acquisition: We have used 5 known prevention levels as a simple approach for dealing with surgical site infections. For gathering information, electronic databases, including Scopus, Medline, ISI, IranMedex, and Irandoc sites were used. Results: For prevention of surgical site infection, a comprehensive evidence based instruction, consist of 75 related factors and 74 proposed measurable and operational preventive activities was developed. Conclusions: We concluded that, to deal with surgical site infections use of the proposed action plan may be useful. Even we believe that, this approach can be used to deal with any health problems including diseases, disorders, accidents and events.