The relationship between outcome and side effects during imatinib treatment of advanced GIST.

e20524 Background: Imatinib is considered to be the first line therapy in patients with unresectable or metastatic gastrointestinal stromal tumors (GIST). The aim of this study was to analyse the occurrence of moderate to severe or life-threatening side effects and clinical outcome. Methods: 75 consecutive patients (41♂), median age 60 years (range 34-81), with GIST, who had received pre- and/ or postoperative imatinib, were retrospectively reviewed. Metastatic disease was present at initiation of imatinib therapy in 37 cases and 38 patients received (neo)adjuvant imatinib due to high or intermediate risk GISTs based on the modified classification of Fletcher-Mietinen. The primary tumor locations were oesophagus (2), stomach (34), duodenum (7), small intestine (24), colorectal (7) and unclear (1). Twenty patients received treatment for a median of 7 months (range 5 days-23 months) preoperatively. Occurrence of moderate-severe or life-threatening side effects, defined in accordance with Common Terminology ...