Appropriate durations of adjuvant imatinib in patients with high-risk gastrointestinal stromal tumor (GIST) the better choice, for the year 2010

Abstract

We report a case of a patient with histopathologically diagnosed GIST who had undergone complete tumor resection for primary localized lesion. The patient has received adjuvant imatinib treatment for at least two years. Studies have shown an improvement in RFS with 1 year of adjuvant imatinib, there is no consensus on the appropriate duration of adjuvant. The 2 year RFS rate in ACOSOG Z9000 was 73%, significantly lower than the 1 year RFS rate of 94%. These findings indicate that 1 year of adjuvant is likely to be insufficient, this implies that an extended duration of adjuvant prolongs RFS in patients with high risk of recurrence. The efficacy of re-challenge with imatinib in the subjects who developed recurrence after drug discontinuation indicates that it was probably due to insufficient treatment duration rather than resistence to imatinib. Waiting the results of phase III trial SSGXVIII/AIO about 3 years of treatment with imatinib we conclude that the better choice, for the year 2010, was to treat patient for at least two years.