[Imatinib, a specific tyrosine-kinase inhibitor, for the treatment of patients with a gastrointestinal stroma cell tumor].

The c-kit oncogene, encoding for a transmembrane growth-factor receptor with tyrosine-kinase activity (KIT), plays an important role in the tumourigenesis of gastrointestinal stroma-cell tumours (GISTs). GISTs are a heterogeneous group of mesenchymal tumours, mainly localised in the abdomen. Immunohistochemical staining using antibodies directed towards the c-kit protein on the cell surface, is a useful tool in the often difficult differential diagnosis of GISTs from other mesenchymal tumours. The correct diagnosis of GISTs is crucial for the new treatment option with imatinib, the tyrosine-kinase inhibitor specifically targeted against KIT. The clinical development of imatinib for patients with GISTs has been extraordinarily rapid. As a result of the short period of time between the drug's experimental introduction and actual registration, many unanswered questions about its use for the treatment of GISTs remain. These can only be answered in well-designed clinical trials. It is therefore recommended that patients with these rare tumours are referred to a centre with experience in the diagnosis and treatment of these soft-tissue sarcomas.