Targeted therapies for sarcomas: new roles for the pathologist.

Sarcomas are a heterogeneous family of mesenchymal malignancies that employ an impressive variety of pathogenetic mechanisms. The traditional role of the pathologist in this field has been to ensure accurate diagnosis and histological grading to direct therapy. More recently, with the advent of targeted therapies directed at particular molecular alterations, the role of the pathologist has expanded and increased awareness of the genetic features of sarcomas is needed to deliver optimal multidisciplinary care. This review discusses these trends and briefly enumerates many of the molecular derangements and targeted agents currently used or under investigation in soft tissue sarcoma. A few sarcomas are highlighted in more detail to illustrate how pathologists can exert positive influence on patient care - not just through diagnosis and grading, but also with molecular characterizations. Featured sarcomas include alveolar soft part sarcoma, dermatofibrosarcoma protuberans, gastrointestinal stromal tumour, inflammatory myofibroblastic tumour and PEComas.