Pathology of soft tissue sarcomas

This article is based on the latest (2002) classification of soft tissue tumors by the World Health Organization (WHO). The WHO currently distinguishes between soft tissue tumors with full malignancy and neoplasms with intermediate malignancy. The latter tumors are divided into locally aggressive forms without metastatic potential and neoplasms with rare metastases (in less than 2% of cases). Considering this classification, tumors of adipocytic, fibroblastic/myofibroblastic, so-called fibrohistiocytic, muscular, vascular, and uncertain differentiation are characterized. Tumors with nerve sheath differentiation have been eliminated from the category of soft tissue tumors. This article also includes some remarks concerning malignancy grading and the certainty of the morphological diagnosis if only very small biopsies are available.