[Gastrointestinal stromal tumor].

Gastrointestinal stromal tumor, i.e., GIST is by far the most common mesenchymal tumor of the gastrointestinal tract. GIST has received special clinical attention, because it is one of the first solid tumors treated with tyrosine kinase inhibitors as targeted oncological therapy. Accordingly, accurate diagnosis of GIST has become clinically increasingly important. While GISTs were previously classified as gastrointestinal smooth muscle or Schwann cell tumors, they are now distinguished as a separate, specific tumor entity. Loss of succinate dehydrogenase complex is a newly understood pathogenesis for 5% of GIST, associated with early onset of disease.