Gastrointestinal stromal tumor workshop

Gastrointestinal stromal tumor (GIST) has emerged in the past year as a pro totypical neoplasm that responds to therapy directed against a single targe t molecule - the KIT receptor tyrosine kinase protein. Although GIST seldom responds to conventional chemotherapeutic agents, early experience with th e tyrosine kinase inhibitor, STI-571 (Gleevec; Novartis, Basel, Switzerland ), has been extremely encouraging. Early results have appeared in a recent case report in the Neu England Journal of Medicine (April 5, 2001),(1) and in early clinical trials from the United States and Europe that were report ed at the plenary session of the American Society of Clinical Oncology in S an Francisco on May 14, 2001. STI-571 is one of the earliest examples of a nontoxic chemotherapeutic agent tan agent whose anticancer activity is not predicated on a cytotoxic mechanism). STI-571 has already shown clinical va lue in BCR-ABL-positive leukemias. Early clinical results in GIST are so en couraging that oncologists may soon be wrestling with the opportunity of re ferring every patient with malignant GIST into clinical trials with STI-571 . To ensure appropriate treatment, pathologists need to understand the biol ogy and treatment of this tumor and to have standard methods and criteria f or providing diagnosis (GIST or not GIST) and consistent prognostic classif ication thigh risk of metastasis or low risk of metastasis).