Imatinib as the first and only treatment in Europe for adult patients at significant risk of relapse following gastrointestinal stromal tumor removal

F Duffaud, S Salas, T Huyn, JL Deville

La Timone University Hospital, Marseille, France

Abstract: Mutations of the KIT gene are the molecular hallmark of most gastrointestinal stromal tumors (GISTs). GIST has become a model for targeted treatment of solid tumors, imatinib becoming the standard first-line treatment of these tumors in the advanced/metastatic phase. Because of the efficacy of imatinib treatment in the advanced setting, its role following resection of a primary non-metastatic GIST was investigated. The recently published phase III, doubleblind, placebo-controlled, multicenter ACOSOG Z9001 study showed that adjuvant therapy is safe, and significantly improves recurrence-free survival compared to placebo when given after resection. To what extent imatinib will improve overall survival has yet to be answered. What is clear is that high-risk GIST patients definitely need adjuvant therapy, and that 1 year of imatinib is not enough for the patients who do need it. The questions of optimal duration of imatinib treatment in the adjuvant setting, adequate selection of risk patients and effect of imatinib on overall survival are currently being studied.

Keywords: GIST, gastrointestinal stromal tumors, imatinib, adjuvant therapy