Solitary fibrous tumor in the lower limb: A rare case report emphasizing the importance of long-term surveillance

Solitary fibrous tumor (SFT) is a rare mesenchymal neoplasm of fibroblastic differentiation, characterized by unpredictable biological behavior. Although initially described in the pleura, it may occur in extrapleural sites, including soft tissues of the limbs, although this is uncommon. The definitive diagnosis relies on histopathological analysis combined with immunohistochemical markers such as CD34 and STAT6, the latter being highly sensitive and specific for SFT. While SFT often exhibits an indolent course, approximately 10–30 % of cases may develop local recurrences or metastases, reinforcing the importance of prognostic risk stratification and long-term follow-up after surgical resection.