Interruption of imatinib (IM) in GIST patients with advanced disease: Updated results of the prospective French Sarcoma Group randomized phase III trial on survival and quality of life

9031 Background: IM (Gleevec/Glivec; Novartis Pharma) the first-line treatment (Tx) for advanced GIST, must be given continuously until disease progression (PD) or intolerance (Blay et al, ASCO 2004). The impact on overall survival (OS) of IM discontinuation in responding patients (pts) and its reintroduction at progression is unknown. Methods: This prospective multicenter BFR14 study was initiated in June 2002. After 1 year of IM 400mg/day, 58 pts free from progression were randomly offered to continue or interrupt Tx until PD. Pts allocated to the interruption (I) arm could restart IM (same dose) in case of PD. Primary endpoint was progression-free survival (PFS); secondary endpoints were OS, quality of life (QoL), secondary response after IM re-introduction, identification of molecular determinants of response. Survival data were compared using the log-rank test. Results: Patient characteristics were well balanced between the two arms. Current median follow-up after randomization is 21 months (range 12...